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What Is Climate Change?

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Climate Change FAQs

You asked. Our scientists answered. Use this guide to have the best info about climate change and how we can solve it together.

December 09, 2018 | Last updated November 13, 2023

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Top Question: What Can I Do About Climate Change?

  • Start a conversation. Talking about climate change is the best way to kickstart action , says Chief Scientist Kath arine Hayhoe.
  • Vote at the ballot box (and the store). At every level, elected leaders have influence on policies that affect us all. And support companies taking climate action.
  • Take personal action. Calculate your carbon footprint and share what you’ve learned to make action contagious.

Climate Change Basics

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Each of these terms describes parts of the same problem—the fact that the average temperature of Earth is rising. As the planet heats up (global warming), we see broad impacts on Earth’s climate, such as shifting seasons, rising sea level, and melting ice.

As the impacts of climate change become more frequent and more severe, they will create—and in many cases they already are creating—crises for people and nature around the world. Many types of extreme weather, including heatwaves, heavy downpours, hurricanes and wildfires are becoming stronger and more dangerous.

Left unchecked, these impacts will spread and worsen, affecting our homes and cities, economies, food and water supplies as well as the species, ecosystems, and biodiversity of this planet we all call home.

All of these terms are accurate, and there’s no perfect one that will make everyone realize the urgency of action. Whatever you choose to call it, the most important thing is that we act to stop it.

Yes, scientists agree that the warming we are seeing today is entirely human-caused.

Climate has changed in the past due to natural factors such as volcanoes, changes in the sun’s energy and the way the Earth orbits the sun.  In fact, these natural factors should be cooling the planet. However, our planet is warming.

Scientists have known for centuries that the Earth has a natural blanket of greenhouse or heat-trapping gases. This blanket keeps the Earth more than 30 degrees Celsius (over 60 degrees Fahrenheit) warmer than it would be otherwise. Without this blanket, our Earth would be a frozen ball of ice.

Greenhouse gases, which include carbon dioxide and methane, trap some of the Earth’s heat that would otherwise escape to space. The more heat-trapping gases in the atmosphere, the thicker the blanket and the warmer it gets.

Over Earth’s history, heat-trapping gas levels have gone up and down due to natural factors. Today, however, by burning fossil fuels, causing deforestation ( forests are key parts of the planet’s natural carbon management systems), and operating large-scale industrial agriculture, humans are rapidly increasing levels of heat-trapping gases in the atmosphere.

The human-caused increase in carbon dioxide in the atmosphere is much greater than any observed in the paleoclimate history (i.e. ancient climate data measured through ice sheets, tree rings, sediments and more) of the earth. As a result, temperature in the air and ocean is now increasing faster than at any time in human history.

Scientists have looked at every other possible reason why climate might be changing today, and their conclusions are clear. There’s no question: it’s us.

One of the main reasons scientists are so worried about climate change is the speed at which it is occurring. In many cases, these changes are happening faster than animals, plants, and ecosystems can safely adapt to – and the same is true for human civilization.

We’ve never seen climate change this quickly, and it is putting our food and water systems, our infrastructure, and even our economies at risk. In some places, these changes are already crossing safe levels for ecosystems and humans.

That’s why, the more we do to mitigate these risks, the better off we will all be.

Effects of Climate Change

Climate change is affecting our planet in many ways. Average temperatures are increasing; rainfall patterns are shifting; snow lines are retreating; glaciers and ice sheets are melting; permafrost is thawing; sea levels are rising ; and severe weather is becoming more frequent.

In particular, heatwaves are becoming more frequent and more intense. Tropical cyclones like hurricanes, typhoons, and cyclones are intensifying faster and dumping more rain. Wildfires are burning greater area, and in many areas around the world, heavy rainfall is becoming more frequent and droughts are getting stronger.

All of these impacts are concerning because they can harm and even potentially lead to the collapse of ecosystems and human systems. And it’s clear that they become more severe  the more heat-trapping gases we produce.

Rapid changes in climate can directly and indirectly impact animals across the world. Many species are approaching—or have already reached—the limit of where they can go to find hospitable climates. In the polar regions, animals like polar bears that live on sea ice are now struggling to survive as that ice melts.

It’s not just how climate change affects an animal directly; it’s about how the warming climate affects the ecosystem and food chain to which an animal has adapted. For example, in the U.S. and Canada, moose are being affected by an increase in ticks and parasites that are surviving the  shorter, milder winters .

In western North America, salmon rely on steady-flowing cold rivers to spawn. As climate change alters the temperature and flow of these waterways, some salmon populations are dwindling. This change in salmon population affects many species that rely on salmon like orcas or grizzly bears.

Changes in temperature and moisture are causing some species to migrate in search of new places to live. For instance, in North America, species are shifting their ranges an average of 11 miles north and 36 feet higher in elevation each decade to find more favorable conditions. The Central Appalachians are one resilient climate escape route  that may help species adapt to changing conditions.

There are some natural places with enough topographical diversity such that, even as the planet warms, they can be  resilient strongholds for plant and animal species . These strongholds serve as breeding grounds and seed banks for many plants and animals that otherwise may be unable to find habitat due to climate change. However, strongholds are not an option for all species, and some plants and animals are blocked from reaching these areas by human development like cities, highways and farmland.

Here at The Nature Conservancy, we use science to identify such locations and work with local partners and communities to do everything we can to protect them.

From reducing agricultural productivity to threatening livelihoods and homes, climate change is affecting people everywhere. You may have noticed how  weather patterns near you are shifting  or how more frequent and severe storms are developing in the spring. Maybe your community is experiencing more severe flooding or  wildfires .

Many areas are even experiencing “sunny day flooding” as rising sea levels cause streets to flood during high tides. In Alaska, some entire coastal communities are being moved because the sea level has risen and what used to be permanently frozen ground has thawed to the point where their original location is no longer habitable.

Climate change also  exacerbates the threat of human-caused conflict  resulting from a scarcity of resources like food and water that become less reliable as growing seasons change and rainfall patterns become less predictable.

Many of these impacts are disproportionately affecting low-income, Indigenous, or marginalized communities. For example, in large cities in North America, low-income communities are often hotter during heatwaves, more likely to flood during heavy downpours, and the last to have their power restored after storms.

Around the globe, many of the poorest nations are being impacted first and most severely by climate change, even though they have contributed far less to the carbon pollution that has caused the warming in the first place. Climate change affects us all, but it doesn’t affect us all equally: and that’s not fair.

Whether you live close to a coast or far from one, what happens in oceans matters to our lives .

Earlier, we described how greenhouse gases trap heat around the planet. Only a small fraction of the extra heat being trapped by the carbon pollution blanket is going into heating up the atmosphere. Almost 90% of the heat is going into the ocean, causing the ocean to warm.

Warmer water takes up more space, causing sea level to rise. As land-based ice melts, this addition of water from land to the ocean causes the ocean to rise even faster.

Warmer oceans can drive fish migrations and lead to coral bleaching and die off.

As the ocean surface warms, it’s less able to mix with deep, nutrient-rich water, which limits the growth of phytoplankton (little plants that serve as the base of the marine food web and that also produce a lot of the oxygen we breathe). This in turn affects the whole food chain.

In addition to taking up heat, the oceans are also absorbing about a quarter of the carbon pollution that humans produce. In addition to warming the air and water of our planet, some of this extra carbon dioxide is being absorbed by the ocean, making our oceans more acidic. In fact, the rate of ocean acidification is the highest it has been in 300 million years!

This acidification negatively impacts many marine habitats and animals, but is a particular threat to shellfish, which struggle to grow shells as water becomes more acidic.

There’s also evidence that warming surface waters may contribute to slowing ocean currents. These currents act like a giant global conveyor belt that transports heat from the tropics toward the poles. This conveyor belt is critical for bringing nutrient-rich waters towards the surface near the poles where giant blooms of food web-supporting phytoplankton occur (this is why the Arctic and Antarctic are known for having such high abundance of fish and marine mammals). With continued warming, these processes may be at risk.

Climate change is disrupting weather patterns, leading to more extreme and frequent heatwaves, droughts, and flooding events that directly threaten harvests. Warmer seasons are also contributing to rising populations of insect pests that eat a higher share of crop yields, and higher carbon dioxide levels are causing plants to grow faster, while decreasing their nutritional content.

Flooding, drought, and heatwaves have decimated crops in China. In Bangladesh, rising sea levels are threatening rice crops. In the midwestern United States, more frequent and intense rains have caused devastating spring flooding, which delays—and sometimes prevents—planting activities.

These impacts make it more difficult for farmers to grow crops and sustain their livelihoods. Globally, one recent study finds that staple crop yield failures will be 4.5 times higher by 2030 and 25 times higher by mid-century. That means a major rice or wheat failure every other year, and higher probabilities of soybean and maize failures.

However, farmers are poised to play a significant role in addressing climate change. Agricultural lands are among the Earth’s largest natural reservoirs of carbon , and when farmers use soil health practices like cover crops, reduced tillage, and crop rotations, they can draw carbon out of the atmosphere .

These practices also help to improve the soil’s water-holding capacity, which is beneficial as water can be absorbed from the soil by crops during times of drought, and during heavy rainfalls, soil can help reduce flooding and run-off by slowing the release of water into streams.

Healthier soils can also improve crop yields, boost farmers’ profitability, and reduce erosion and fertilizer runoff from farm fields, which in turn means cleaner waterways for people and nature. That’s why climate-smart agriculture is a win-win!

Solutions to Climate Change

Yes, deforestation, land use change, and agricultural emissions are responsible for about a quarter of heat-trapping gas emissions from human activities. Agricultural emissions include methane from livestock digestion and manure, nitrous oxide from fertilizer use, and carbon dioxide from land use change.

Forests are one of our most important types of natural carbon storage , so when people cut down forests, they lose their ability to store carbon. Burning trees—either through wildfires or controlled burns-- releases even more carbon into the atmosphere.

Forests are some of the best natural climate solutions we have on this planet. If we can slow or stop deforestation , manage natural land so that it is healthy, and use other natural climate solutions such as climate-smart agricultural practices, we could achieve up to one third of the emission reductions needed by 2030 to keep global temperatures from rising more than 2°C (3.6°F). That’s the equivalent of the world putting a complete stop to burning oil.

When it comes to climate change, there’s no one solution that will fix it all. Rather, there are many solutions that, together, can address this challenge at scale while building a safer, more equitable, and greener world.

First, we need to reduce our heat-trapping gas emissions as much as possible, as soon as possible. Through efficiency and behavioral change, we can reduce the amount of energy we need.

At the same time, we have to  transition all sectors of our economy away from fossil fuels  that emit carbon, through increasing our use of clean energy sources like wind and solar. This transition will happen much faster and more cost-effectively if governments enact an economy-wide price on carbon.

Second, we need to harness the power of nature to capture carbon and deploy agricultural practices and technologies that capture and store carbon. Our research shows that proper land management of forests and farmlands, also called natural climate solutions, can provide up to one-third of the emissions reductions necessary to reach the Paris Climate Agreement’s goal.

The truth, however, is that even if we do successfully reach net zero carbon emissions by 2050, we will still have to address harmful climate impacts. That’s why there is a third category of climate solutions that is equally important: adaptation to the impacts of global warming.

Adaptation consists of helping our human and natural systems prepare for the impacts of a warming planet. Greening urban areas helps protect them from heat and floods; restoring coastal wetlands helps protect from storm surge; increasing the diversity of ecosystems helps them to weather heat and drought; growing super-reefs helps corals withstand marine heatwaves. There are many ways we can use technology, behavioral change, and nature to work together to make us more resilient to climate impacts.

Climate change affects us all, but it doesn’t affect us all equally or fairly. We see how sea level rise threatens communities of small island states like Kiribati and the Solomon Islands and of low-lying neighborhoods in coastal cities like Mumbai, Houston and Lagos. Similarly, people living in many low-income neighborhoods in urban areas in North America are disproportionately exposed to heat and flood risk due to a long history of racist policies like redlining.

Those who have done the least to contribute to this problem often bear the brunt of the impacts and have the fewest resources to adapt. That’s why it is particularly important to help vulnerable communities adapt and become more resilient to climate change.

We need to  increase renewable energy at least nine-fold  from where it is today to meet the goals of the Paris Agreement and avoid the worst climate change impacts. Every watt that we can reduce through efficiency or shift from fossil fuel to renewables like wind power or solar power is a step in the right direction.

The best science we have tells us that to avoid the worst impacts of global warming, we must globally achieve net-zero carbon emissions no later than 2050. To do this, the world must immediately identify pathways to reduce carbon emissions from all sectors: transportation, agriculture, electricity, and industry. This cannot be achieved without a major shift to renewable energy.

Clean energy and technological innovation are not only helping mitigate climate change, but also helping create jobs and support economic growth in communities across the world. Renewable energy such as wind and solar have experienced remarkable growth and huge cost improvements over the past decade with no signs of slowing down.

Prices are declining rapidly, and renewable energy is becoming increasingly competitive with fossil fuels all around the world. In some places, new renewable energy is already cheaper than continuing to operate old, inefficient, and dirty fossil fuel-fired power plants.

However, it’s important that renewable energy development isn’t built at the expense of protecting unique ecosystems or important agricultural lands. Without proactive planning, renewable energy developments could displace up to 76 million acres of farm and wildlife habitat—an area the size of Arizona.

Fortunately, TNC studies have found that  we can meet clean energy demand 17 times over  without converting more natural habitat. The key is to deploy new energy infrastructure on the wealth of previously converted areas such as agricultural lands, mine sites, and other transformed terrain, at a  lower cost .

Thoughtful planning is required at every step. For instance, much of the United States’ wind potential is in the Great Plains, a region with the best remaining grassland habitat on the continent. TNC has mapped out the right places to site wind turbines  in this region in order to catalyze renewable energy responsibly, and we’re doing the same analysis for India and Europe as well.

There can also be unique interventions to protect wildlife where clean energy has already been developed. In Kenya, for instance, a wind farm employs biodiversity monitors to watch for migrating birds , and can order individual turbines to shut down in less than a minute.

The Nature Conservancy is committed to tackling the dual crises of climate change and biodiversity loss. These two crises are, as our chief scientist says, two sides of the same coin .

What we do between now and 2030 will determine if we get on track to meet the targets of the Paris Agreement while also conserving enough land and water to slow accelerated species loss. That’s why we have ambitious 2030 goals that focus on people and the planet.

We're combatting these dual crises by:

  • Enhancing nature’s ability to draw down and store carbon across forests, farmlands and wetlands by  accelerating the deployment of natural climate solutions .
  • Mobilizing action for a clean energy future  and new, low-carbon technologies in harmony with nature.
  • Supporting the leadership of Indigenous Peoples and local communities .
  • Building resilience through natural defenses such as restored reefs, mangroves and wetlands that reduce the impact of storms and floods.
  • Restoring and bolstering the resilience of vulnerable ecosystems like coral reefs and coastal wetlands.
  • Helping countries around the globe, like India and Croatia , implement and enhance their commitments to the Paris Agreement.

Visit  Our Goals for 2030  to learn more about TNC’s actions and partnerships to tackle climate change this decade.

Why We Must Urgently Act on Climate

Some amount of change has already occurred, and some future changes are inevitable due to our past choices. However, the good news is that we know what causes it and what to do to stop it. It will take courage, ambition, and a push to create change, but it can be done.

Reaching net zero carbon emissions by 2050 is an ambitious goal, one that’s going to require substantial effort across every sector of the economy. We don’t have a lot of time, but if we are prepared to act now, and act together, we can substantially reduce the rate of global warming and prevent the worst impacts of climate change from coming to pass.

The even better news is that the low carbon economy that we need to create will also give us cleaner air, more abundant food and water, more affordable energy choices, and safer cities. Likewise, many of the solutions to even today’s climate change impacts benefit both people and nature.

When we really understand the benefits of climate action—how it will lead us to a world that is safer and healthier, more just and equitable—the only question we have left is: What are we waiting for?

Scientific studies show that climate change, if unchecked, would overwhelm our communities and pose an existential threat to certain ecosystems.

These catastrophic impacts include sea level rise from melting ice sheets in Greenland and Antarctica that would flood most major global coastal cities; increasingly common and more severe storms, droughts, and heatwaves; massive crop failures and water shortages; and the large-scale destruction of habitats and ecosystems, leading to species extinctions .

To avoid the worst of climate change, the Intergovernmental Panel on Climate Change (IPCC) says that “every bit of warming matters.” When it comes to limiting climate change, there’s no magic threshold: the faster we reduce our emissions, the better off we will be.

In 2015, all the countries in the world came together and signed the Paris Agreement . It’s a legally binding international treaty in which signatories agree to hold “the increase in the global average temperature to well below 2°C (3.5° F) above pre-industrial levels” and pursue efforts “to limit the temperature increase to 1.5°C (2.7°F) above pre-industrial levels.”

Every day that goes by, we are releasing carbon into the atmosphere and increasing our planetary risk. Scientists agree that we need to begin reducing carbon emissions  RIGHT NOW .

To reach the goal of the Paris Agreement, the world must make significant progress toward decarbonization (reducing carbon from the atmosphere and replacing fossil fuels in our economies) by 2030 and commit ourselves to reaching net zero carbon emissions by 2050. This is no small feat and will require a range of solutions applied together, to reach the goal.

As the IPCC says, “every action matters.” You can be part of the climate change solution and you can activate others, too.

It’s really important that we use our voices for climate action.  Tell your policy makers that you care about climate change  and want to see them enact laws and policies that address greenhouse gas emissions and climate impacts.

One of the simplest—and most important—things that everyone can do is to  talk about climate change with family and friends . We know these conversations can seem like a recipe for discord and hard feelings. It starts with meeting people where they are. TNC has resources to help you break the climate silence and pave the way for action on global warming.

You can also talk about climate change where you work, and with any other organization you’re part of. Join an organization that shares your values and priorities, to help amplify your voice. Collective change begins with understanding the risks climate change poses and the actions that can be taken together to reduce emissions and build resilience.

Lastly, you can calculate your carbon footprint  and take actions individually or with your family and friends to lower it. You might be surprised which of your activities are emitting the most heat-trapping gases. But don’t forget to talk about the changes you’ve made, to help make them contagious —contagious in a good way, of course!

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Talking About Climate

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COP28: Your Guide to the 2023 UN Climate Change Conference in UAE

COP28 takes place November 30-December 12, 2023 in United Arab Emirates. This guide will tell you what to expect at COP28, why TNC will be there, and what it all means for you.

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Renewable Energy Transition

We no longer need to choose between abundant energy and a cleaner environment. A renewable energy revolution is happening across the globe.

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Six Tough Questions About Climate Change

NASA's supercomputer model created this simulation of carbon dioxide in the atmosphere. Photo: NASA/GSFC

Whenever the focus is on climate change, as it is right now at the  Paris climate conference , tough questions are asked concerning the costs of cutting carbon emissions, the feasibility of transitioning to renewable energy, and whether it’s already too late to do anything about climate change. We posed these questions to Laura Segafredo , manager for the Deep Decarbonization Pathways Project . The decarbonization project comprises energy research teams from 16 of the world’s biggest greenhouse gas emitting countries that are developing concrete strategies to reduce emissions in their countries. The Deep Decarbonization Pathways Project is an initiative of the Sustainable Development Solutions Network .

  • Will the actions we take today be enough to forestall the direct impacts of climate change? Or is it too little too late?

There is still time and room for limiting climate change within the 2˚C limit that scientists consider relatively safe, and that countries endorsed in Copenhagen and Cancun. But clearly the window is closing quickly. I think that the most important message is that we need to start really, really soon, putting the world on a trajectory of stabilizing and reducing emissions. The temperature change has a direct relationship with the cumulative amount of emissions that are in the atmosphere, so the more we keep emitting at the pace that we are emitting today, the more steeply we will have to go on a downward trajectory and the more expensive it will be.

Today we are already experiencing an average change in global temperature of .8˚. With the cumulative amount of emissions that we are going to emit into the atmosphere over the next years, we will easily reach 1.5˚ without even trying to change that trajectory.

Assateague Island National Seashore where the potential for storm surges and flooding is higher due to sea level rise.

Two degrees might still be doable, but it requires significant political will and fast action. And even 2˚ is a significant amount of warming for the planet, and will have consequences in terms of sea level rise, ecosystem changes, possible extinctions of species, displacements of people, diseases, agriculture productivity changes, health related effects and more. But if we can contain global warming within those 2˚, we can manage those effects. I think that’s really the message of the Intergovernmental Panel on Climate Change reports—that’s why the 2˚ limit was chosen, in a sense. It’s a level of warming where we can manage the risks and the consequences. Anything beyond that would be much, much worse.

  • Will taking action make our lives better or safer, or will it only make a difference to future generations?

It will make our lives better and safer for sure. For example, let’s think about what it means to replace a coal power plant with a cleaner form of energy like wind or solar. People that live around the coal power plant are going to have a lot less air pollution, which means less asthma for children, and less time wasted because of chronic or acute diseases. In developing countries, you’re talking about potentially millions of lives saved by replacing dirty fossil fuel based power generation with clean energy.

It will also have important consequences for agricultural productivity. There’s a big risk that with the concentration of carbon and other gases in the atmosphere,   agricultural yields will be reduced, so preventing that means more food for everyone.

Light rail in Seattle. Photo: Michael B.

And then think about cities. If you didn’t have all that pollution from cars, we could live in cities that are less noisy, where the air’s much better, and have potentially better transportation. We could live in better buildings where appliances are more efficient. And investing in energy efficiency would basically leave more money in our pockets. So there are a lot of benefits that we can reap almost immediately, and that’s without even considering the biggest benefit—leaving a planet in decent condition for future generations.

  • How will measures to cut carbon emissions affect my life in terms of cost?

To build a climate resilient economy, we need to incorporate the three pillars of energy system transformation that we focus on in all the deep decarbonization pathways. Number one is improving energy efficiency in every part of the economy—buildings, what we use inside buildings, appliances, industrial processes, cars…everything you can think of can perform the same service, but using less energy. What that means is that you will have a slight increase in the price in the form of a small investment up front, like insulating your windows or buying a more efficient car, but you will end up saving a lot more money over the life of the equipment in terms of decreased energy costs.

Tehachapi wind farm, CA. Photo: Stan Shebs

The second pillar is making electricity, the power sector, carbon-free by replacing dirty power generation with clean power sources. That’s clearly going to cost a little money, but those costs are coming down so quickly. In fact there are already a lot of clean technologies that are at cost parity with fossil fuels— for example, onshore wind is already as competitive as gas—and those costs are only coming down in the future. We can also expect that there are going to be newer technologies. But in any event, the fact that we’re going to use less power because of the first pillar should actually make it a wash in terms of cost.

The Australian deep decarbonization teams have estimated that even with the increased costs of cleaner cars, and more efficient equipment for the home, etc., when the power system transitions to where it’s zero carbon, you still have savings on your energy bills compared to the previous situation.

The third pillar that we think about are clean fuels, essentially zero-carbon fuels. So we either need to electrify everything— like cars and heating, once the power sector is free of carbon—or have low-carbon fuels to power things that cannot be electrified, such as airplanes or big trucks. But once you have efficiency, these types of equipment are also more efficient, and you should be spending less money on energy.

Saving money depends on the three pillars together, thinking about all this as a whole system.

  • Given that renewable sources provide only a small percentage of our energy and that nuclear power is so expensive, what can we realistically do to get off fossil fuels as soon as possible?

There are a lot of studies that have been done for the U.S. and for Europe that show that it’s very realistic to think of a power sector that is almost entirely powered by renewables by 2050 or so. It’s actually feasible—and this considers all the issues with intermittency, dealing with the networks, and whatever else represents a technological barrier—that’s all included in these studies. There’s also the assumption that energy storage, like batteries, will be cheaper in the future.

That is the future, but 2050 is not that far away. 35 years for an energy transition is not a long time. It’s important that this transition start now with the right policy incentives in place. We need to make sure that cars are more efficient, that buildings are more efficient, that cities are built with more public transit so less fossil fuels are needed to transport people from one place to another.

I don’t want people to think that because we’re looking at 2050, that means that we can wait—in order to be almost carbon free by 2050, or close to that target, we need to act fast and start now.

  • Will the remedies to climate change be worse than the disease? Will it drive more people into poverty with higher costs?

I actually think the opposite is true. If we just let climate go the way we are doing today by continuing business as usual, that will drive many people into poverty. There’s a clear relationship between climate change and changing weather patterns, so more significant and frequent extreme weather events, including droughts, will affect the livelihoods of a large portion of the world population. Once you have droughts or significant weather events like extreme precipitation, you tend to see displacements of people, which create conflict, and conflict creates disease.

Syrian Kurdish refugees enter Turkey. Photo: EC/ECHO

I think Syria is a good example of the world that we might be going towards if we don’t do anything about climate change. Syria is experiencing a once-in-a-century drought, and there’s a significant amount of desertification going on in those areas, so you’re looking at more and more arid areas. That affects agriculture, so people have moved from the countryside to the cities and that has created a lot of pressure on the cities. The conflict in Syria is very much related to the drought, and the drought can be ascribed to climate change.

And consider the ramifications of the Syrian crisis: the refugee crisis in Europe, terrorism, security concerns and 7 million-plus people displaced. I think that that’s the world that we’re going towards. And in a world like that, when you have to worry about people being safe and alive, you certainly cannot guarantee wealth and better well-being, or education and health.

  • So finally, doing what needs to be done to combat climate change all comes down to political will?

The majority of the American public now believe that climate change is real, that it’s human induced and that we should do something about it.

Photo: Matt Brown

But there’s seems to be a disconnect between what these numbers seem to indicate and what the political discourse is like… I can’t understand it, yet it seems to be the situation.

I’m a little concerned because other more immediate concerns like terrorism and safety always come first. Because the effects of climate change are going to be felt a little further away, people think that we can always put it off. The Department of Defense, its top-level people, have made the connection between climate change and conflict over the next few decades. That’s why I would argue that Syria is actually a really good example to remind us that if we are experiencing security issues today, it’s also because of environmental problems. We cannot ignore them.

The reality is that we need to do something about climate change fast—we don’t have time to fight this over the next 20 years. We have to agree on this soon and move forward and not waste another 10 years debating.

Read the Deep Decarbonization Pathways Project 2015 report . The full report will be released Dec. 2.

LAURA bigger

Laura Segafredo was a senior economist at the ClimateWorks Foundation, where she focused on best practice energy policies and their impact on emission trajectories. She was a lead author of the 2012 UNEP Emissions Gap Report and of the Green Growth in Practice Assessment Report. Before joining ClimateWorks, Segafredo was a research economist at Electricité de France in Paris.

She obtained her Ph.D. in energy studies and her BA in economics from the University of Padova (Italy), and her MSc in economics from the University of Toulouse (France).

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Many find low wages prohibits saving. Changing personal vehicles and heating systems costs. Will there be financial support for people on low wages?

Julie Ament

The energy innovation and dividend bill has already been introduced in the house. It’s a carbon fee and dividend plan. The carbon fee rises every year and 100% of it goes back directly into the hands of the people by a check each month. This helps offset rising costs, especially for lower income folks.

Andrea

81 cosponsors now Tell your rep in Congress to support this HR 763!

Alex

Results show that yields for all four crops grown at levels of carbon dioxide remaining at 2000 levels would experience severe declines in yield due to higher temperatures and drier conditions. But when grown at doubled carbon dioxide levels, all four crops fare better due to increased photosynthesis and crop water productivity, partially offsetting the impacts from those adverse climate changes. For wheat and soybean crops, in terms of yield the median negative impacts are fully compensated, and rice crops recoup up to 90 percent and maize up to 60 percent of their losses.

Gary

When is Russia, China, and Mexico going to work toward a better environment instead of the United States trying to do it all? They continue to pollute like they have for years. Who is going to stop the deforestation of the rain forest?

blake leinberger

I’m curious if climate change has any effect on seismic activity. It seems with ice melting on the poles and increasing water dispersement and temp of that water, it might cause the plates to shift to compensate. Is there any evidence of this?

RILEs

this isn’t because of doldrums or jet streams. the pattern keeps having the same action. we must save trees :3

Guy Bernard Lalanne

How long do we have, before it’s too late?

rose

Climate Change isn’t nearly as big of a deal as everyone makes it out to be. Meaning no disrespect to the author, but I really don’t see how this is something that we should be worrying about given that one human recycling their soda cans or getting their old phone refurbished rather than dumping it isn’t going to restore the polar ice caps or lower the temperature of the planet. And supposedly agriculture is the problem, but I point-blank refuse to give up my beef night, or bacon and eggs for breakfast on Saturdays. Also, nuclear power is supposed to be a solution, but the building of the power plants is going to add more greenhouse gases than the plant will take out. The whole planet needs a reality check. Earth isn’t going to explode because it’s slightly hotter than it used to be!

Dayandan Villegas

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This explainer was updated by Umair Irfan in December 2018 and draws heavily from a card stack written by Brad Plumer in 2015. Brian Resnick contributed the section on the Paris climate accord in 2017.

There’s a vast and growing gap between the urgency to fight climate change and the policies needed to combat it.

In 2018, the United Nations’ Intergovernmental Panel on Climate Change found that it is possible to limit global warming to 1.5 degrees Celsius this century, but the world may have as little as 12 years left to act. The US government’s National Climate Assessment , with input from NASA, the Environmental Protection Agency, and the Pentagon, also reported that the consequences of climate change are already here, ranging from nuisance flooding to the spread of mosquito-borne viruses into what were once colder climates. Left unchecked, warming will cost the US economy hundreds of billions of dollars.

However, these facts have failed to register with the Trump administration, which is actively pushing policies that will increase the emissions of heat-trapping gases.

Ever since he took office, President Donald Trump has rejected or undermined President Barack Obama’s signature climate achievements: the Paris climate agreement; the Clean Power Plan , the main domestic policy for limiting greenhouse gas emissions; and fuel economy standards , which target transportation, the largest US source of greenhouse gases.

At the same time, the Trump administration has aggressively boosted fossil fuels: opening unprecedented swaths of public lands to mining and drilling , attempting to bail out foundering coal power plants , and promoting hydrocarbon exploitation at climate change conferences .

Trump has also appointed climate change skeptics to key positions. Quietly, officials at these and other science agencies have been removing the words “climate change” from government websites and press releases.

Yet the evidence for humanity’s role in changing the climate continues to mount, and its consequences are increasingly difficult to ignore. Atmospheric carbon dioxide concentrations now top 408 parts per million, a threshold the planet hasn’t seen in millions of years . Greenhouse gas emissions reached a record high in 2018. Disasters worsened by climate change have taken hundreds of lives, destroyed thousands of homes, and cost billions of dollars.

The big questions now are how these ongoing changes in the climate will reverberate throughout the rest of the world, and what we should do about them. The answers bridge decades of research across geology, economics, and social science, which have been confounded by uncertainty and obscured by jargon. That’s why it can be a bit daunting to join the discussion for the first time, or to revisit the conversation after a hiatus.

To help, we’ve provided answers to some fundamental questions about climate change you may have been afraid to ask.

1) What is global warming?

In short: The world is getting hotter, and humans are responsible.

Yes, the planet’s temperature has changed before, but it’s the rise in average temperature of the Earth's climate system since the late 19th century, the dawn of the Industrial Revolution, that’s important here. Temperatures over land and ocean have gone up 0.8° to 1° Celsius (1.4° to 1.8° Fahrenheit), on average, in that span:

research questions about global warming

Many people use the term “climate change” to describe this rise in temperatures and the associated effects on the Earth's climate. (The shift from the term “global warming” to “climate change” was also part of a deliberate messaging effort by a Republican pollster to undermine support for environmental regulations.)

Like detectives solving a murder, climate scientists have found humanity’s fingerprints all over the planet’s warming, with the overwhelming majority of the evidence pointing to the extra greenhouse gases humans have put into the atmosphere by burning fossil fuels. Greenhouse gases like carbon dioxide trap heat at the Earth’s surface, preventing that heat from escaping back out into space too quickly. When we burn coal, natural gas, or oil for energy, or when we cut down forests that usually soak up greenhouse gases, we add even more carbon dioxide to the atmosphere, so the planet warms up.

Global warming also refers to what scientists think will happen in the future if humans keep adding greenhouse gases to the atmosphere.

Though there is a steady stream of new studies on climate change, one of the most robust aggregations of the science remains the Intergovernmental Panel on Climate Change’s fifth assessment report from 2013. The IPCC is convened by the United Nations, and the report draws on more than 800 expert authors. It projects that temperatures could rise at least 2°C (3.6°F) by the end of the century under many plausible scenarios — and possibly 4°C or more. A more recent study by scientists in the United Kingdom found a narrower range of expected temperatures if atmospheric carbon dioxide doubled, rising between 2.2°C and 3.4°C.

Many experts consider 2°C of warming to be unacceptably high , increasing the risk of deadly heat waves, droughts, flooding, and extinctions. Rising temperatures will drive up global sea levels as the world’s glaciers and ice sheets melt. Further global warming could affect everything from our ability to grow food to the spread of disease.

That’s why the IPCC put out another report in 2018 comparing 2°C of warming to a scenario with 1.5°C of warming . The researchers found that this half-degree difference is actually pretty important, since every bit of warming matters. Between the two outlooks, less warming means fewer people will have to move from coastal areas, natural weather events will be less severe, and economies will take a smaller hit.

However, limiting warming would likely require a complete overhaul of our energy system. Fossil fuels currently provide just over 80 percent of the world’s energy. To zero out emissions this century, we’d have to replace most of that with low-carbon sources like wind, solar, nuclear, geothermal, or carbon capture.

Beyond that, we may have to electrify everything that uses energy and start pulling greenhouse gases straight from the air. And to get on track for 1.5°C of warming, the world would have to halve greenhouse gas emissions from current levels by 2030.

That’s a staggering task, and there are huge technological and political hurdles standing in the way. As such, the world's nations have been slow to act on global warming — many of the existing targets for curbing greenhouse gas emissions are too weak , yet many countries are falling short of even these modest goals.

2) How do we know global warming is real?

The simplest way is through temperature measurements. Agencies in the United States, Europe, and Japan have independently analyzed historical temperature data and reached the same conclusion: The Earth’s average surface temperature has risen roughly 0.8° Celsius (1.4° Fahrenheit) since the early 20th century.

But that’s not the only clue. Scientists have also noted that glaciers and ice sheets around the world are melting. Satellite observations since the 1970s have shown warming in the lower atmosphere. There’s more heat in the ocean, causing water to expand and sea levels to rise. Plants are flowering earlier in many parts of the world. There’s more humidity in the atmosphere. Here’s a summary from the National Oceanic and Atmospheric Administration:

research questions about global warming

These are all signs that the Earth really is getting warmer — and that it’s not just a glitch in the thermometers. That explains why climate scientists say things like , “Warming in the climate system is unequivocal.” They’re really confident about this one.

3) How do we know humans are causing global warming?

Climate scientists say they are more than 95 percent certain that human influence has been the dominant cause of global warming since 1950. They’re about as sure of this as they are that cigarette smoke causes cancer.

Why are they so confident? In part because they have a good grasp of how greenhouse gases can warm the planet, in part because the theory fits the available evidence, and in part because alternate theories have been ruled out. Let's break it down in six steps:

1) Scientists have long known that greenhouse gases in the atmosphere — such as carbon dioxide, methane, or water vapor — absorb certain frequencies of infrared radiation and scatter them back toward the Earth. These gases essentially prevent heat from escaping too quickly back into space, trapping that radiation at the surface and keeping the planet warm.

2) Climate scientists also know that concentrations of greenhouse gases in the atmosphere have grown significantly since the Industrial Revolution. Carbon dioxide has risen 45 percent . Methane has risen more than 200 percent . Through some relatively straightforward chemistry and physics , scientists can trace these increases to human activities like burning oil, gas, and coal.

3) So it stands to reason that more greenhouse gases would lead to more heat. And indeed, satellite measurements have shown that less infrared radiation is escaping out into space over time and instead returning to the Earth’s surface. That’s strong evidence that the greenhouse effect is increasing.

4) There are other human fingerprints that suggest increased greenhouse gases are warming the planet. For instance, back in the 1960s, simple climate models predicted that global warming caused by more carbon dioxide would lead to cooling in the upper atmosphere (because the heat is getting trapped at the surface). Later satellite measurements confirmed exactly that . Here are a few other similar predictions that have also been confirmed.

research questions about global warming

5) Meanwhile, climate scientists have ruled out other explanations for the rise in average temperatures over the past century. To take one example: Solar activity can shift from year to year, affecting the Earth's climate. But satellite data shows that total solar irradiance has declined slightly in the past 35 years, even as the Earth has warmed.

6) More recent calculations have shown that it’s impossible to explain the temperature rise we’ve seen in the past century without taking the increase in carbon dioxide and other greenhouse gases into account. Natural causes, like the sun or volcanoes, have an influence, but they’re not sufficient by themselves.

Ultimately, the Intergovernmental Panel on Climate Change concluded that most of the warming since 1951 has been due to human activities. The Earth’s climate can certainly fluctuate from year to year due to natural forces (including oscillations in the Pacific Ocean, such as El Niño ). But greenhouse gases are driving the larger upward trend in temperatures.

And as the Climate Science Special Report , released by 13 US federal agencies in November 2017, put it, “For the warming over the last century, there is no convincing alternative explanation supported by the extent of the observational evidence.”

More: This chart breaks down all the different factors affecting the Earth’s average temperature. And there’s much more detail in the IPCC’s report , particularly this section and this one .

4) How has global warming affected the world so far?

Here’s a list of ongoing changes that climate scientists have concluded are likely linked to global warming, as detailed by the IPCC here and here .

Higher temperatures: Every continent has warmed substantially since the 1950s. There are more hot days and fewer cold days, on average, and the hot days are hotter.

Heavier storms and floods : The world’s atmosphere can hold more moisture as it warms. As a result, the overall number of heavier storms has increased since the mid-20th century, particularly in North America and Europe (though there’s plenty of regional variation). Scientists reported in December that at least 18 percent of Hurricane Harvey’s record-setting rainfall over Houston in August was due to climate change.

Heat waves: Heat waves have become longer and more frequent around the world over the past 50 years, particularly in Europe, Asia, and Australia.

Shrinking sea ice: The extent of sea ice in the Arctic, always at its maximum in winter, has shrunk since 1979, by 3.3 percent per decade. Summer sea ice has dwindled even more rapidly, by 13.2 percent per decade. Antarctica has seen recent years with record growth in sea ice, but it’s a very different environment than the Arctic, and the losses in the north far exceed any gains at the South Pole, so total global sea ice is on the decline:

Global, Arctic and Antarctic Sea Ice Area Spiral February 2018 #GlobalWarming #ClimateChange pic.twitter.com/gayoLFSJ5u — Kevin Pluck (@kevpluck) March 1, 2018

Shrinking glaciers and ice sheets : Glaciers around the world have, on average, been losing ice since the 1970s. In some areas, that is reducing the amount of available freshwater. The ice sheet on Greenland, which would raise global sea levels by 25 feet if it all melted, is declining, with some sections experiencing a sudden surge in the melt rate. The Antarctic ice sheet is also getting smaller, but at a much slower rate .

Sea level rise: Global sea levels rose 9.8 inches (25 centimeters) in the 19th and 20th centuries, after 2,000 years of relatively little change , and the pace is speeding up . Sea level rise is caused by both the thermal expansion of the oceans — as water warms up, it expands — and the melting of glaciers and ice sheets (but not sea ice).

Food supply: A hotter climate can be both good for crops (it lengthens the growing season, and more carbon dioxide can increase photosynthesis) and bad for crops (excess heat can damage plants). The IPCC found that global warming was currently benefiting crops in some high-latitude areas but that negative effects are becoming increasingly common worldwide. In areas like California, crop yields are estimated to decline 40 percent by 2050.

Shifting species: Many land and marine species have had to shift their geographic ranges in response to warmer temperatures. So far, several extinctions have been linked to global warming, such as certain frog species in Central America.

Warmer winters: In general, winters are warming faster than summers . Average low temperatures are rising all over the world. In some cases, these temperatures are climbing above the freezing point of water. We’re already seeing massive declines in snow accumulation in the United States, which can paradoxically increase flood, drought, and wildfire risk — as water that would ordinarily dispatch slowly over the course of a season instead flows through a region all at once.

Debated impacts

Here are a few other ways the Earth’s climate has been changing — but scientists are still debating whether and how they’re linked to global warming:

Droughts have become more frequent and more intense in some parts of the world — such as the American Southwest, Mediterranean Europe, and West Africa — though it’s hard to identify a clear global trend. In other parts of the world, such as the Midwestern United States and Northwestern Australia, droughts appear to have become less frequent. A recent study shows that, globally, the time between droughts is shrinking and more areas are affected by drought and taking longer to recover from them.

Hurricanes have clearly become more intense in the North Atlantic Ocean since 1970, the IPCC says. But it’s less clear whether global warming is driving this. 2017 was an exceptionally bad year for Atlantic hurricanes in terms of strength and damage. And while scientists are still uncertain whether they were a fluke or part of a trend, they are warning we should treat it as a baseline year. There doesn’t yet seem to be any clear trajectory for tropical cyclones worldwide.

5) What impacts will global warming have in the future?

It depends on how much the planet actually heats up. The changes associated with 4° Celsius (or 7.2° Fahrenheit) of warming are expected to be more dramatic than the changes associated with 2°C of warming.

Here’s a basic rundown of big impacts we can expect if global warming continues, via the IPCC ( here and here ).

Hotter temperatures: If emissions keep rising unchecked, then global average surface temperatures will be at least 2°C higher (3.6°F) than preindustrial levels by 2100 — and possibly 3°C or 4°C or more.

Higher sea level rise: The expert consensus is that global sea levels will rise somewhere between 0.2 and 2 meters by the end of the century if global warming continues unchecked (that’s between 0.6 and 6.6 feet). That’s a wide range, reflecting some of the uncertainties scientists have in how ice will melt. In specific regions like the Eastern United States, sea level rise could be even higher, and around the world, the rate of rise is accelerating .

Heat waves: A hotter planet will mean more frequent and severe heat waves .

Droughts and floods: Across the globe, wet seasons are expected to become wetter, and dry seasons drier. As the IPCC puts it , the world will see “more intense downpours, leading to more floods, yet longer dry periods between rain events, leading to more drought.”

Hurricanes: It’s not yet clear what impact global warming will have on tropical cyclones. The IPCC said it was likely that tropical cyclones would get stronger as the oceans heat up, with faster winds and heavier rainfall. But the overall number of hurricanes in many regions was likely to “either decrease or remain essentially unchanged.”

Heavier storm surges: Higher sea levels will increase the risk of storm surges and flooding when storms do hit.

Agriculture: In many parts of the world, the mix of increased heat and drought is expected to make food production more difficult. The IPCC concluded that global warming of 1°C or more could start hurting crop yields for wheat, corn, and rice by the 2030s, especially in the tropics. (This wouldn’t be uniform, however; some crops may benefit from mild warming, such as winter wheat in the United States.)

research questions about global warming

Extinctions: As the world warms, many plant and animal species will need to shift habitats at a rapid rate to maintain their current conditions. Some species will be able to keep up; others likely won’t. The Great Barrier Reef, for instance, may not be able to recover from major recent bleaching events linked to climate change. The National Research Council has estimated that a mass extinction event “could conceivably occur before the year 2100.”

Long-term changes: Most of the projected changes above will occur in the 21st century. But temperatures will keep rising after that if greenhouse gas levels aren’t stabilized. That increases the risk of more drastic longer-term shifts. One example: If West Antarctica’s ice sheet started crumbling, that could push sea levels up significantly. The National Research Council in 2013 deemed many of these rapid climate surprises unlikely this century but a real possibility further into the future.

6) What happens if the world heats up more drastically — say, 4°C?

The risks of climate change would rise considerably if temperatures rose 4° Celsius (7.2° Fahrenheit) above preindustrial levels — something that’s possible if greenhouse gas emissions keep rising at their current rate.

The IPCC says 4°C of global warming could lead to “substantial species extinctions,” “large risks to global and regional food security,” and the risk of irreversibly destabilizing Greenland’s massive ice sheet.

One huge concern is food production: A growing number of studies suggest it would become significantly more difficult for the world to grow food with 3°C or 4°C of global warming. Countries like Bangladesh, Egypt, Vietnam, and parts of Africa could see large tracts of farmland turn unusable due to rising seas. Scientists are also concerned about crops getting less nutritious due to rising CO2.

Humans could struggle to adapt to these conditions. Many people might think the impacts of 4°C of warming will simply be twice as bad as those of 2°C. But as a 2013 World Bank report argued, that’s not necessarily true. Impacts may interact with each other in unpredictable ways. Current agriculture models, for instance, don’t have a good sense of what will happen to crops if increased heat waves, droughts, new pests and diseases, and other changes all start to combine.

“Given that uncertainty remains about the full nature and scale of impacts,” the World Bank report said, “there is also no certainty that adaptation to a 4°C world is possible.” Its conclusion was blunt: “The projected 4°C warming simply must not be allowed to occur.”

7) What do climate models say about the warming that could actually happen in the coming decades?

That depends on your faith in humanity.

Climate models depend on not only complicated physics but the intricacies of human behavior over the entire planet.

Generally, the more greenhouse gases humanity pumps into the atmosphere, the warmer it will get. But scientists aren’t certain how sensitive the global climate system is to increases in greenhouse gases. And just how much we might emit over the coming decades remains an open question, depending on advances in technology and international efforts to cut emissions.

The IPCC groups these scenarios into four categories of atmospheric greenhouse gas concentrations known as Representative Concentration Pathways . They serve as standard benchmarks for evaluating climate models, but they also have some assumptions baked in .

RCP 2.6, also called RCP 3PD, is the scenario with very low greenhouse gas concentrations in the atmosphere. It bets on declining oil use, a population of 9 billion by 2100, increasing energy efficiency, and emissions holding steady until 2020, at which point they’ll decline and even go negative by 2100. This is, to put it mildly, very optimistic.

The next tier up is RCP 4.5, which still banks on ambitious reductions in emissions but anticipates an inflection point in the emissions rate around 2040. RCP 6 expects emissions to increase 75 percent above today’s levels before peaking and declining around 2060 as the world continues to rely heavily on fossil fuels.

The highest tier, RCP 8.5, is the pessimistic business-as-usual scenario, anticipating no policy changes nor any technological advances. It expects a global population of 12 billion and triple the rate of carbon dioxide emissions compared to today by 2100.

Here’s how greenhouse gas emissions under each scenario stack up next to each other:

research questions about global warming

And here’s what that means for global average temperatures, assuming that a doubling of carbon dioxide concentrations in the atmosphere leads to 3°C of warming:

research questions about global warming

As you can see, RCP 3PD is the only trajectory that keeps the planet below 2°C of warming. Recall what it would take to keep emissions in line with this pathway and you’ll understand the enormity of the challenge of meeting this goal.

8) How do we stop global warming?

The world’s nations would need to cut their greenhouse gas emissions by a lot. And even that wouldn’t stop all global warming.

For example, let’s say we wanted to limit global warming to below 2°C. To do that, the IPCC has calculated that annual greenhouse gas emissions would need to drop at least 40 to 70 percent by midcentury.

Emissions would then have to keep falling until humans were hardly emitting any extra greenhouse gases by the end of the century. We’d also have to remove carbon dioxide from the atmosphere .

Cutting emissions that sharply is a daunting task. Right now, the world gets 87 percent of its primary energy from fossil fuels: oil, gas, and coal. By contrast, just 13 percent of the world’s primary energy is “low carbon”: a little bit of wind and solar power, some nuclear power plants, a bunch of hydroelectric dams. That’s one reason global emissions keep rising each year.

To stay below 2°C, that would all need to change radically. By 2050, the IPCC notes, the world would need to triple or even quadruple the share of clean energy it uses — and keep scaling it up thereafter. Second, we’d have to get dramatically more efficient at using energy in our homes, buildings, and cars. And stop cutting down forests. And reduce emissions from agriculture and from industrial processes like cement manufacturing.

The IPCC also notes that this task becomes even more difficult the longer we put it off, because carbon dioxide and other greenhouse gases will keep piling up in the atmosphere in the meantime, and the cuts necessary to stay below the 2°C limit become more severe.

9) What are we actually doing to fight climate change?

A global problem requires global action, but with climate change, there is a yawning gap between ambition and action.

The main international effort is the 2015 Paris climate accord, of which the United States is the only country in the world that wants out . The deal was hammered out over weeks of tense negotiations and weighs in at 31 pages . What it does is actually pretty simple.

The backbone is the global target of keeping global average temperatures from rising 2°C (compared to temperatures before the Industrial Revolution) by the end of the century. Beyond 2 degrees, we risk dramatically higher seas, changes in weather patterns, food and water crises, and an overall more hostile world.

Critics have argued that the 2-degree mark is arbitrary, or even too low , to make a difference. But it’s a starting point, a goal that, before Paris, the world was on track to wildly miss.

research questions about global warming

Paris is voluntary

To accomplish this 2-degree goal, the accord states that countries should strive to reach peak emissions “as soon as possible.” (Currently, we’re on track to hit peak emissions around 2030 or later , which will likely be too late.)

But the agreement doesn’t detail exactly how these countries should do that. Instead, it provides a framework for getting momentum going on greenhouse gas reduction, with some oversight and accountability. For the US, the pledge involves 26 to 28 percent reductions by 2025. (Under Trump’s current policies, that goal is impossible .)

There’s also no defined punishment for breaking it. The idea is to create a culture of accountability (and maybe some peer pressure) to get countries to step up their climate game.

In 2020, delegates are supposed to reconvene and provide updates about their emission pledges and report on how they’re becoming more aggressive on accomplishing the 2-degree goal.

However, many countries are already falling behind on their climate change commitments, and some, like Germany, are giving up on their near-term targets.

Paris asks richer countries to help out poorer countries

There’s a fundamental inequality when it comes to global emissions. Rich countries have plundered and burned huge amounts of fossil fuels and gotten rich from them. Poor countries seeking to grow their economies are now being admonished for using the same fuels. Many low-lying poor countries also will be among the first to bear the worst impacts of climate change.

The main vehicle for rectifying this is the Green Climate Fund , via which richer countries, like the US, are supposed to send $100 billion a year in aid and financing by 2020 to the poorer countries. The United States’ share was $3 billion , but with President Trump’s decision to withdraw from the Paris accord, this goal is unlikely to be met.

The agreement matters because we absolutely need momentum on this issue

The Paris agreement is largely symbolic, and it will live on even though Trump is aiming to pull the US out. But, as Jim Tankersley wrote for Vox , “the accord will be weakened, and, much more importantly, so will the fragile international coalition” around climate change.

We’re already seeing the Paris agreement lose steam. At a follow-up climate meeting this year in Katowice, Poland , negotiators forged an agreement on measuring and verifying their progress in cutting greenhouse gases, but left many critical questions of how to achieve these reductions unanswered.

But the Paris accord isn’t the only international climate policy game in town

There are regional international climate efforts like the European Union’s Emissions Trading System . However, the most effective global policy at keeping warming in check to date doesn’t have to do with climate change, at least on the surface.

The 1987 Montreal Protocol , which was convened by countries to halt the destruction of the ozone layer, had a major side effect of averting warming. In fact, it’s been the single most effective effort humanity has undertaken to fight climate change. Since many of the substances that eat away at the ozone layer are potent heat-trappers, limiting emissions of gases like chlorofluorocarbons has an outsize effect.

research questions about global warming

And the Trump administration doesn’t appear as hostile to Montreal as it does to Paris. The White House may send the 2016 Kigali Amendment to the Montreal Protocol to the Senate for ratification, giving the new regulations the force of law. If implemented, the amendment would avert 0.5°C of warming by 2100.

Regardless of what path we choose, the key thing to remember is that we are going to pay for climate change one way or another. We have the opportunity now to address warming on our own terms, with investments in clean energy, moving people away from disaster-prone areas, and regulating greenhouse gas emissions. Otherwise, we’ll pay through diminished crop harvests, inundated coastlines, destroyed homes, lost lives, and an increasingly unlivable planet. Ignoring or stalling on climate change chooses the latter option by default. Our choices do matter, but we’re running out of time to make them.

F urther reading:

Avoiding catastrophic climate change isn’t impossible yet. Just incredibly hard.

Reckoning with climate change will demand ugly tradeoffs from environmentalists — and everyone else

Show this cartoon to anyone who doubts we need huge action on climate change

It’s time to start talking about “negative” carbon dioxide emissions

A history of the 2°C global warming target

Scientists made a detailed “roadmap” for meeting the Paris climate goals. It’s eye-opening.

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Research articles

research questions about global warming

Global warming decreases connectivity among coral populations

The authors develop a high-resolution model of coral larval dispersal for the southern Great Barrier Reef. They show that 2 °C of warming decreases larval dispersal distance and connectivity of reefs, hampering post-disturbance recovery and the potential spread of warm-adapted genes.

  • Joana Figueiredo
  • Christopher J. Thomas
  • Emmanuel Hanert

research questions about global warming

Phenological mismatches between above- and belowground plant responses to climate warming

The authors conduct a meta-analysis to reveal mismatches in above- and belowground plant phenological responses to warming that differ by plant type (herbaceous versus woody). The work highlights a need for further research and consideration of under-represented belowground phenological changes.

  • Huiying Liu
  • Madhav P. Thakur

research questions about global warming

Near-term transition and longer-term physical climate risks of greenhouse gas emissions pathways

There is a balance in mitigation pathway design between economic transition cost and physical climate threats. This study provides a comprehensive framework to assess the near- and long-term risks under various warming scenarios globally and in particular regions.

  • Ajay Gambhir
  • Seth Monteith

research questions about global warming

Hysteresis of the intertropical convergence zone to CO 2 forcing

In idealized model experiments where CO 2 increases four-fold before returning to its original level, temperature and precipitation show almost linear responses to CO 2 forcing. In contrast, the response of the Intertropical Convergence Zone lags behind CO 2 changes, associated with delayed energy exchanges.

  • Jong-Seong Kug
  • Jongsoo Shin

research questions about global warming

Contextualizing cross-national patterns in household climate change adaptation

The context and motivation around adaptation are influenced by local culture and institutions. In the United States, China, Indonesia and the Netherlands, some factors (such as perceived costs) have similar influences on household adaptation to flooding, but others (such as flood experience) differ between countries.

  • Brayton Noll
  • Tatiana Filatova
  • Alessandro Taberna

research questions about global warming

Ocean warming and accelerating Southern Ocean zonal flow

The remoteness and paucity of historic observations of the Southern Ocean limit understanding of the effects of climate change on circulation. Using observations, CMIP6 and eddy-resolving models, this Article shows that acceleration of its zonal flow emerged in recent decades as a result of uneven ocean warming.

  • Jia-Rui Shi
  • Lynne D. Talley

research questions about global warming

Cost and attainability of meeting stringent climate targets without overshoot

Current emissions scenarios include pathways that overshoot the temperature goals set out in the Paris Agreement and rely on future net negative emissions. Limiting overshoot would require near-term investment but would result in longer-term economic benefit.

  • Keywan Riahi
  • Christoph Bertram
  • Behnam Zakeri

research questions about global warming

Net zero-emission pathways reduce the physical and economic risks of climate change

Mitigation pathways allowing for temperature overshoot often ignore the related climate and macroeconomic impacts. Net-zero pathways with limited overshoot could reduce low-probability high-consequence risks and economic loss.

  • Laurent Drouet
  • Valentina Bosetti
  • Massimo Tavoni

research questions about global warming

Health co-benefits of climate change mitigation depend on strategic power plant retirements and pollution controls

Climate mitigation policies often provide health co-benefits. Analysis of individual power plants under future climate–energy policy scenarios shows reducing air pollution-related deaths does not automatically align with emission reduction policies and that policy design needs to consider public health.

  • Guannan Geng
  • Steven J. Davis

research questions about global warming

Climate action with revenue recycling has benefits for poverty, inequality and well-being

Climate policy analyses often ignore the possibility of progressive redistribution of carbon tax revenues and assume that mitigation cost will burden the poor in the short term. Integrated Assessment Model (IAM) estimation suggests such redistribution could reduce inequality, alleviate poverty and increase well-being globally.

  • Mark Budolfson
  • Francis Dennig
  • Stéphane Zuber

research questions about global warming

Observed increases in extreme fire weather driven by atmospheric humidity and temperature

Climate change has led to increased fire activity in parts of the globe due to observed increases in fire weather extremes. These trends are driven predominantly by decreasing relative humidity and increasing temperature.

  • Piyush Jain
  • Dante Castellanos-Acuna
  • Mike D. Flannigan

research questions about global warming

Climate and land-use changes reduce the benefits of terrestrial protected areas

The authors project future rates of temporal and spatial displacement of climate and land-use in protected areas (PAs), and show that more than one-quarter of the world’s PAs are highly threatened, with particular risk to PAs across tropical moist and grassland biomes.

  • Ernest F. Asamoah
  • Linda J. Beaumont
  • Joseph M. Maina

research questions about global warming

Demand-side solutions to climate change mitigation consistent with high levels of well-being

Evaluation of mitigation actions often focuses on cost and overlooks the direct effects on well-being. This work shows demand-side measures have large mitigation potential and beneficial effects on well-being outcomes.

  • Felix Creutzig
  • Leila Niamir
  • Diana Ürge-Vorsatz

research questions about global warming

A multi-model analysis of long-term emissions and warming implications of current mitigation efforts

Mitigation pathways tend to focus on an end temperature target and calculate how to keep within these bounds. This work uses seven integrated assessment models to consider current mitigation efforts and project likely temperature trajectories.

  • Ida Sognnaes
  • Glen P. Peters

research questions about global warming

Risk transfer policies and climate-induced immobility among smallholder farmers

Smallholder farmers will be impacted substantially by climate change and need to adapt. Agent-based modelling shows that interventions, particularly cash transfer paired with risk transfer mechanisms, lead to increased migration and uptake of cash crops, with higher income and lower inequality.

  • Nicolas Choquette-Levy
  • Matthias Wildemeersch
  • Simon A. Levin

research questions about global warming

Climatic limit for agriculture in Brazil

Soybean and maize yields in the Amazon-Cerrado region of Brazil are dependent on water from rain. Warming and drying will make the climate less suitable for agricultural production; changes have already moved 28% of croplands out of their optimum climate space.

  • Ludmila Rattis
  • Paulo M. Brando
  • Michael T. Coe

research questions about global warming

Anthropogenic emissions and urbanization increase risk of compound hot extremes in cities

Heat extremes threaten the health of urban residents with particularly strong impacts from day–night sustained heat. Observation and simulation data across eastern China show increasing risks of compound events attributed to anthropogenic emissions and urbanization.

research questions about global warming

A systematic global stocktake of evidence on human adaptation to climate change

Determining progress in adaptation to climate change is challenging, yet critical as climate change impacts increase. A stocktake of the scientific literature on implemented adaptation now shows that adaptation is mostly fragmented and incremental, with evidence lacking for its impact on reducing risk.

  • Lea Berrang-Ford
  • A. R. Siders
  • Thelma Zulfawu Abu

research questions about global warming

Threatened salmon rely on a rare life history strategy in a warming landscape

Highlighting the importance of rare phenotypes in population persistence, the authors show that spring-run Chinook salmon late-migrant juveniles were critical for cohort success in drought and ocean heatwave years. Combined further warming and impassable dams threaten these late migrants’ survival.

  • F. Cordoleani
  • C. C. Phillis
  • R. C. Johnson

research questions about global warming

Impact of high-speed rail on road traffic and greenhouse gas emissions

Intercity high-speed rail (HSR) can have large climate benefits with its high energy efficiency. This study explores the substitution effects of HSR on road traffic in China, which can be translated to an annual reduction of 14.76 million tons of CO 2 -equivalent emissions.

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  • In Response to Climate Change, Citizens in Advanced Economies Are Willing To Alter How They Live and Work

Many doubt success of international efforts to reduce global warming

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  • Acknowledgments
  • Methodology

Photo showing mud-covered cars stand piled up near Bad Neuenahr-Ahrweiler in western Germany on July 22, days after deadly floods caused major damage in the region. (Christof Stache/AFP via Getty Images)

This analysis focuses on attitudes toward global climate change around the world. For this report, we conducted nationally representative Pew Research Center surveys of 16,254 adults from March 12 to May 26, 2021, in 16 advanced economies. All surveys were conducted over the phone with adults in Canada, Belgium, France, Germany, Greece, Italy, the Netherlands, Spain, Sweden, the UK, Australia, Japan, New Zealand, Singapore, South Korea and Taiwan.

In the United States, we surveyed 2,596 U.S. adults from Feb. 1 to 7, 2021. Everyone who took part in the U.S. survey is a member of the Center’s American Trends Panel (ATP), an online survey panel that is recruited through national, random sampling of residential addresses. This way nearly all adults have a chance of selection. The survey is weighted to be representative of the U.S. adult population by gender, race, ethnicity, partisan affiliation, education and other categories.

This study was conducted in countries where nationally representative telephone surveys are feasible. Due to the coronavirus outbreak, face-to-face interviewing is not currently possible in many parts of the world.

Here are the questions used for the report, along with responses. See our methodology database for more information about the survey methods outside the U.S. For respondents in the U.S., read more about the ATP’s methodology .

A new Pew Research Center survey in 17 advanced economies spanning North America, Europe and the Asia-Pacific region finds widespread concern about the personal impact of global climate change. Most citizens say they are willing to change how they live and work at least some to combat the effects of global warming, but whether their efforts will make an impact is unclear.

People across world greatly concerned about climate change and willing to make  sacrifices to address it, but there is less confidence in efforts to solve the problem

Citizens offer mixed reviews of how their societies have responded to climate change, and many question the efficacy of international efforts to stave off a global environmental crisis.

Conducted this past spring, before the summer season ushered in new wildfires , droughts , floods and stronger-than-usual storms , the study reveals a growing sense of personal threat from climate change among many of the publics polled. In Germany, for instance, the share that is “very concerned” about the personal ramifications of global warming has increased 19 percentage points since 2015 (from 18% to 37%).

Intense concern about the personal effects of climate change has increased sharply in several major economies since 2015

In the study, only Japan (-8 points) saw a significant decline in the share of citizens deeply concerned about climate change. In the United States, views did not change significantly since 2015.

Younger adults tend to be more concerned than older counterparts that climate change will harm them

Young adults, who have been at the forefront of some of the most prominent climate change protests in recent years, are more concerned than their older counterparts about the personal impact of a warming planet in many publics surveyed. The widest age gap is found in Sweden, where 65% of 18- to 29-year-olds are at least somewhat concerned about the personal impacts of climate change in their lifetime, compared with just 25% of those 65 and older. Sizable age differences are also found in New Zealand, Australia, the U.S., France and Canada.

Public concern about climate change appears alongside a willingness to reduce its effects by taking personal steps. Majorities in each of the advanced economies surveyed say they are willing to make at least some changes in how they live and work to address the threat posed by global warming. And across all 17 publics polled, a median of 34% are willing to consider “a lot of changes” to daily life as a response to climate change.

Ideological left is more willing to adjust lifestyle in response to climate change

Generally, those on the left of the political spectrum are more open than those on the right to taking personal steps to help reduce the effects of climate change. This is particularly true in the U.S., where citizens who identify with the ideological left are more than twice as willing as those on the ideological right (94% vs. 45%) to modify how they live and work for this reason. Other countries where those on the left and right are divided over whether to alter their lives and work in response to global warming include Canada, the Netherlands, Australia and Germany.

Beyond individual actions, the study reveals mixed views on the broader, collective response to climate change. In 12 of the 17 publics polled, half or more think their own society has done a good job dealing with global climate change. But only in Singapore (32%), Sweden (14%), Germany (14%), New Zealand (14%) and the United Kingdom (13%) do more than one-in-ten describe such efforts as “very good.” Meanwhile, fewer than half in Japan (49%), Italy (48%), the U.S. (47%), South Korea (46%) and Taiwan (45%) give their society’s climate response favorable marks.

Abroad, the U.S. response to climate change is generally seen as wanting. Among the 16 other advanced economies surveyed, only Singaporeans are slightly positive in their assessment of American efforts (53% say the U.S. is doing a “good job” of addressing climate change). Elsewhere judgments are harsher, with six-in-ten or more across Australia, New Zealand and many of the European publics polled saying the U.S. is doing a “bad job” of dealing with global warming. However, China fares substantially worse in terms of international public opinion: A median of 78% across 17 publics describe China’s handling of climate change as “bad,” including 45% who describe the Chinese response as “very bad.” That compares with a cumulative median of 61% who judge the American response as “bad.”

Internationally, EU, UN climate response earns mostly high praise, while U.S. and China get poor marks

At the cross-national level, the European Union’s response to climate change is viewed favorably by majorities in each of the advanced economies surveyed, except Germany where opinion is split (49% good job; 47% bad job). However, there is still room for improvement, as only a median of 7% across the publics polled describe the EU’s efforts as “very good.” The United Nations’ actions to address global warming are also generally seen in a favorable light: A median of 56% say the multilateral organization is doing a good job. But again, the reviews are tempered, with just 5% describing the UN’s response to climate change as “very good.”

Publics in the advanced economies surveyed are divided as to whether actions by the international community can successfully reduce the effects of global warming. Overall, a median of 52% lack confidence that a multilateral response will succeed, compared with 46% who remain optimistic that nations can respond to the impact of climate change by working together. Skepticism of multilateral efforts is most pronounced in France (65%), Sweden (61%) and Belgium (60%), while optimism is most robust in South Korea (68%) and Singapore (66%).

These are among the findings of a new Pew Research Center survey, conducted from Feb. 1 to May 26, 2021, among 18,850 adults in 17 advanced economies.

People concerned climate change will harm them during their lifetimes

Many are concerned climate change will personally harm them during their lifetimes

Many people across 17 advanced economies are concerned that global climate change will harm them personally at some point in their lifetime. A median of 72% express at least some concern that they will be personally harmed by climate change in their lifetimes, compared with medians of 19% and 11% who say they are not too or not at all concerned, respectively. The share who say they are very concerned climate change will harm them personally ranges from 15% in Sweden to 57% in Greece.

Roughly two-thirds of Canadians and six-in-ten Americans are worried climate change will harm them in their lifetimes. Only 12% of Canadians and 17% of Americans are not at all concerned about the personal impact of global climate change.

Publics in Europe express various degrees of concern for potential harm caused by climate change. Three-quarters or more of those in Greece, Spain, Italy, France and Germany say they are concerned that climate change will harm them at some point during their lives. Only in Sweden does less than a majority of adults express concern about climate change harming them. Indeed, 56% of Swedes are not concerned about personal harm related to climate change.

In general, Asia-Pacific publics express more worry about climate change causing them personal harm than not. The shares who express concern range from 64% in Australia to 88% in South Korea. About one-third or more in South Korea, Singapore and Australia say they are very concerned climate change will harm them personally.

Rising concern that climate change will cause personal harm

The share who are very concerned climate change will harm them personally at some point during their lives has increased significantly since 2015 in nearly every country where trend data is available. In Germany, for example, the share who say they are very concerned has increased 19 percentage points over the past six years. Double-digit changes are also present in the UK (+18 points), Australia (+16), South Korea (+13) and Spain (+10). The only public where concern for the harm from climate change has decreased significantly since 2015 is Japan (-8 points).

While many worry climate change will harm them personally in the future, there is widespread sentiment that climate change is already affecting the world around them. In Pew Research Center surveys conducted in 2019 and 2020, a median of 70% across 20 publics surveyed said climate change is affecting where they live a great deal or some amount. And majorities in most countries included as part of a 26-nation survey in 2018 thought global climate change was a major threat to their own country (the same was true across all 14 countries surveyed in 2020 ).

Those on ideological left are more likely to be concerned about personal harm of climate change than those on the right

Those who place themselves on the left of the ideological spectrum are more likely than those who place themselves on the right to be concerned global climate change will harm them personally during their lifetime. This pattern is present across all 14 nations where ideology is measured. In 10 of these 14, though, majorities across the ideological left, center and right are concerned climate change will harm them personally.

The difference is starkest in the U.S.: Liberals are 59 percentage points more likely than conservatives to express concern for this possibility (87% vs. 28%, respectively). However, large ideological differences are also present in Australia (with liberals 41 points more likely to say this), the Netherlands (+35), Canada (+30), Sweden (+30) and New Zealand (+23).

Women are more concerned about the harm of climate change than men in many advanced economies

Women are more concerned than men that climate change will harm them personally in many of the publics polled. In Germany, women are 13 points more likely than men to be concerned that climate change will cause them harm (82% vs 69%, respectively). Double-digit differences are also present across several publics, including the U.S., Sweden, the UK, South Korea, Singapore, Taiwan, Australia and the Netherlands.

When this question was first asked in 2015 , women were also more likely to express concern than their male counterparts that climate change will harm them in the U.S., Germany, Canada, Japan, Spain and Australia.

Young people have been at the forefront of past protests seeking government action on climate change. In eight places surveyed, young adults ages 18 to 29 are more likely than those 65 and older to be concerned climate change will harm them during their lifetime. The difference is greatest in Sweden, home of youth climate activist Greta Thunberg . Young Swedes are 40 points more likely than their older counterparts to say they are concerned about harm from climate change. Large age gaps are also present in New Zealand (with younger adults 31 points more likely to say this), Australia (+30) and Singapore (+20). And young Americans, French, Canadians and Brits are also more likely to say that climate change will personally harm them in their lifetimes.

While large majorities across every age group in Greece and South Korea are concerned climate change will harm them personally, those ages 65 and older are more likely to hold this sentiment than those younger than 30.

Many across the world willing to change how they live and work to reduce effects of climate change

Most people in publics surveyed are willing to make at least some changes to their lives to help reduce the effects of climate change

Many across the publics surveyed say they are willing to make at least some changes to the way they live and work to reduce the effects of climate change. A median of 80% across 17 publics say they would make at least some changes to their lives to reduce the effects of climate change, compared with a median of 19% who say they would make a few changes or no changes at all. The share willing to make a lot of changes ranges from 8% in Japan to 62% in Greece.

In North America, about three-quarters or more of both Canadians and Americans say they are willing to make changes to reduce the effects of climate change.

Large majorities across each of the European publics surveyed say they are willing to change personal behavior to address climate change, but the share who say they are willing to make a lot of changes varies considerably. About half or more in Greece, Italy and Spain say they would make a lot of changes, while fewer than a third in Belgium, Germany and the Netherlands say the same.

Young adults are more likely than older adults in some countries to be willing to make lifestyle changes to help reduce the effects of climate change

Majorities in each of the Asia-Pacific publics polled say they would make some or a lot of changes to how they live and work to combat the effects of climate change, including more than three-quarters in South Korea, Singapore, Australia and New Zealand. But in Japan, fully 44% say they are willing to make few or no changes to how they live and work to address climate change, the largest share of any public surveyed.

In eight countries surveyed, those ages 18 to 29 are more likely than those 65 and older to say they are willing to make at least some changes to how they live and work to help reduce the effects of climate change. In France, for example, about nine-in-ten of those younger than 30 are willing to make changes in response to climate change, compared with 62% of those 65 and older.

Willingness to change behavior to reduce effects of climate change is tied to education

Ideologically, those on the left are more likely than those on the right to express willingness to change their behavior to help reduce the effects of global climate change. The ideological divide is widest in the U.S., where 94% of liberals say they are willing to make at least some changes to how they live and work to help reduce the effects of climate change, compared with 45% of conservatives. Large ideological differences are also present between those on the left and the right in Canada (a difference of 26 percentage points), the Netherlands (25 points), Australia (23 points) and Germany (22 points).

In most publics, those with more education are more likely than those with less education to say they are willing to adjust their lifestyles in response to the impact of climate change. 1 In Belgium, for example, those with a postsecondary degree or higher are 14 points more likely than those with a secondary education or below to say they are willing to make changes to the way they live. Double-digit differences are also present between those with more education and less education in France, Germany, New Zealand, the Netherlands and Australia.

And in most places surveyed, those with a higher-than-median income are more likely than those with a lower income to express willingness to make at least some changes to reduce the effects of climate change. For example, in Belgium, about three-quarters (76%) of those with a higher income say they would make changes to their lives, compared with 66% of those with a lower income.

Many are generally positive about how their society is handling climate change

Majorities in Europe confident in own public’s response to climate change

Respondents give mostly positive responses when asked to reflect on how their own society is handling climate change. Around half or more in most places say they their society is doing at least a somewhat good job, with a median of 56% saying this across the 17 advanced economies.

Roughly two-thirds (64%) of Canadians say their country is doing a good job, while nearly half of Americans say the same.

In most of the European publics surveyed, majorities believe their nation’s climate change response is at least somewhat good. Those in Sweden and the UK are especially optimistic, with around seven-in-ten saying their society is doing a good job dealing with climate change. In Europe, Italians are the most critical of their country’s performance: 20% say their society is doing a very bad job, the largest share among all publics surveyed.

Ideological divides in evaluation of climate change handling

Around eight-in-ten in Singapore and New Zealand say their publics are doing a good job – the highest levels among all societies surveyed. This includes around a third (32%) in Singapore who say they are doing a very good job. Adults in the other Asia-Pacific publics surveyed are more circumspect; about half or fewer say their society is doing a good job.

Political ideology plays a role in how people evaluate their own public’s handling of climate change. For adults in 10 countries, those on the right tend to rate their country’s performance with regard to climate change more positively. The difference is most stark in Australia: 69% of those on the right say Australia is handling climate change well, compared with just 19% of those on the left – a 50-point difference. A striking difference also appears in the U.S., where conservatives are 41 points more likely than liberals to say the U.S. is doing a good job dealing with climate change.

Evaluations are also tied to how people view governing parties. In 10 of 17 publics surveyed, people who see the governing party positively are more likely than those with a negative view of the party to think climate change is being handled well. The opposite is true in the U.S., where only 33% of Democrats and Democratic-leaning independents say the U.S. is handling climate change well, compared with 61% of those who do not support the Democratic Party.

Mixed views on whether action by the international community can reduce the effects of climate change

Doubts that international community can reduce effects of climate change are common but not ubiquitous

Only a median of 46% across the publics polled are confident that actions taken by the international community will significantly reduce the effects of climate change. A median of 52% are not confident these actions will reduce the effects of climate change.

Canadians are generally divided on whether international climate action can reduce the impact of climate change. And 54% of Americans are not confident in the international community’s response to the climate crisis.

In Europe, majorities in Germany and the Netherlands express confidence that international climate action can significantly address climate change. However, majorities in France, Sweden, Belgium and Italy are not confident in climate actions taken by the international community.

South Koreans and Singaporeans say they are confident in international climate action, but elsewhere in the Asia-Pacific region, public opinion is either divided or leans toward pessimism about international efforts.

Those with a favorable view of UN  more likely to have confidence in international climate change action

Opinion of international organizations, like the United Nations, is linked to confidence that actions taken by the international community will significantly reduce the effects of global climate change. Those with a favorable view of the UN are more confident that actions taken by the international community will significantly reduce the effects of climate change than those with an unfavorable view of the UN. This difference is largest in the U.S., where 61% with a favorable view of the UN say international action will reduce the effects of climate change, compared with just 22% of those with an unfavorable view of the organization. Double-digit differences are present in every public polled.

Similarly, in every EU member state included in the survey, those with favorable views of the bloc are more likely to have confidence in international efforts to combat climate change than those with unfavorable views.

Little consensus on whether international climate action will harm or benefit domestic economies

Publics are divided over the economic impact of international actions to address global climate change

Relatively few in the advanced economies surveyed think actions taken by the international community to address climate change, such as the Paris climate agreement, will mostly benefit or harm their own economy. A median of 31% across 17 publics say these actions will be good for their economy, while a median of 24% believe such actions will mostly harm their economy. A median of 39% say actions like the Paris climate agreement will have no economic impact.

In Sweden, about half (51%) feel international climate actions will mostly benefit their economy. On the other hand, only 18% in France say their public will benefit economically from international climate agreements.

In no public do more than a third say international action on climate change will harm their economy. But in the U.S., which pulled out of the Paris climate agreement under former President Donald Trump and has just recently rejoined the accord under President Joe Biden, a third say international climate agreements will harm the economy. (For more on how international publics view Biden’s international policy actions, see “ America’s Image Abroad Rebounds With Transition From Trump to Biden .”)

The more widespread sentiment among those surveyed is that climate actions will have no impact on domestic economies. In eight publics, four-in-ten or more hold this opinion, including half in France. And in two places – Japan and Taiwan – one-in-five or more offer no opinion.

Left-leaning adults are generally more likely than those on right to see climate change efforts as boon to economy

Those on the left of the ideological spectrum are more likely than those on the right to say international action to address climate change – such as the Paris Agreement – will mostly benefit their economies. U.S. respondents are particularly divided by ideology. Roughly half (53%) of liberals feel international actions related to climate change will benefit the U.S. economy, compared with just 12% of conservatives. The next largest difference is in Canada, where those on the left are 24 percentage points more likely than those on the right to think this type of international action will benefit their economy.

Those on the right in many publics are, in turn, more likely than those on the left to think international actions such as the Paris Agreement will mostly harm their economies. Here again, ideological divisions in the U.S. are much larger than those in other publics: 65% of conservatives say international climate change actions will harm the American economy, compared with 12% of liberals who say the same.

In several advanced economies, those who say their current economic situation is good are more likely to say that actions taken by the international community to address climate change will mostly benefit their economies than those who say the economic situation is bad. In Sweden, for example, a majority (55%) of those who say the current economic situation is good also believe international action like the Paris Agreement will benefit the Swedish economy, compared with 31% who are more negative about the state of the economy.

Evaluating the climate change response from the EU, UN, U.S. and China

In addition to reflecting on their own public, respondents were asked to evaluate how four international organizations or countries are handling global climate change. Of the entities asked about, the European Union receives the best ratings, with a median of 63% across the 17 publics surveyed saying the EU is doing a good job handling climate change. A median of 56% say the same for the United Nations. Far fewer believe the U.S. or China – the two leading nations in carbon dioxide emissions – are doing a good job.

EU and UN receive generally higher ratings on climate response than U.S. or China

EU handling of climate change receives high marks in and outside of Europe

Majorities praise the EU’s response to global climate change

Majorities in all but two of the publics surveyed think the EU is doing a good job addressing climate change. However, this positivity is tempered, with most respondents saying the EU’s effort is somewhat good, but few saying it is very good.

Praise for the bloc’s response to climate change is common among the European countries surveyed. In Spain and Greece, around seven-in-ten say the EU is doing at least a somewhat good job, and about six-in-ten or more in the UK, Italy, Sweden and France agree. The Dutch and Germans have more mixed feelings about how the EU is responding to climate change. Notably, only about one-in-ten say the EU is doing a very bad job handling climate change in every European country surveyed but Sweden, where only 5% say so.

Seven-in-ten Canadians believe the EU is doing a good job dealing with climate change, and 62% in the U.S. express the same view.

The Asia-Pacific publics surveyed report similarly positive attitudes on the EU’s climate plans. Around seven-in-ten Australians and Singaporeans consider the EU’s response to climate change at least somewhat good. About six-in-ten or more in New Zealand, South Korea, Japan and Taiwan echo this sentiment.

Climate change actions by UN seen positively among most surveyed

UN response to global climate change elicits generally positive responses

Majorities in most publics also consider the UN response to climate change to be good. A median of 49% across all publics surveyed say that the UN’s actions are somewhat good, and a median of 5% say the actions are very good.

Canadians evaluate the UN’s performance on climate more positively than Americans do. In Canada, roughly six-in-ten say the multilateral organization is doing at least a somewhat good job handling climate change. About half of those in the U.S. agree with that evaluation, with 43% of Americans saying the UN is doing a bad job of dealing with climate change.

In Europe, majorities in Spain, Sweden, the UK, Greece and Italy approve of how the UN is dealing with climate change. Fewer than half of adults in the Netherlands, France and Belgium agree with this evaluation, and only about a third in Germany say the same.

Singaporeans stand out as the greatest share of adults among those surveyed who see the UN’s handling of climate change as good. This includes 14% who say the UN response is very good, which is at least double the share in all other societies surveyed. Majorities in Australia and New Zealand similarly say that the UN is doing a good job.

Many critical of U.S. approach to climate change

Most disapprove of U.S. handling of climate change

In most publics surveyed, adults who say the U.S. is doing a good job of handling climate change are in the minority. A median of 33% say the U.S. is doing a somewhat good job, and a median of just 3% believe the U.S. is doing a very good job.

About half of Americans say their own country is doing a good job in dealing with global climate change, but six-in-ten Canadians say their southern neighbor is doing a bad job.

Ideological right is more enthusiastic about U.S. approach to climate change

Across Europe, most think the U.S. is doing a bad job of addressing climate change, including 75% of Germans and Swedes. And at least a quarter in all European nations surveyed except the UK and Greece say the U.S. is doing a very bad job.

Singaporeans offer the U.S. approach to climate change the most praise in the Asia-Pacific region and across all publics surveyed; around half say they see the U.S. strategy positively. New Zealanders are the most critical in the Asia-Pacific region: Only about a quarter say the U.S. is doing at least a somewhat good job.

Political ideology is linked to evaluations of the U.S. climate strategy. In 12 countries, those on the right of the political spectrum are significantly more likely than those on the left to say the U.S. is doing a good job dealing with global climate change. The difference is greatest in Australia, Canada and Italy.

Few give China positive marks for handling of climate change

Advanced economies disapprove of how China is handling global climate change

The publics surveyed are unenthusiastic about how China is dealing with climate change. A median of 18% across the publics say China is doing a good job, compared with a median of 78% who say the opposite. Notably, a median of 45% say that China is doing a very bad job handling climate change.

Just 18% of Americans and Canadians believe China is doing a good job handling climate change.

Similarly, few in Europe think China is dealing effectively with climate change. In fact, more than four-in-ten in nearly all European countries polled say China is doing a very bad job with regards to climate change. Criticism is less common in Greece, where a third give China positive marks for its climate change action.

Adults in the Asia-Pacific region also generally give China poor ratings for dealing with climate change. South Koreans are exceptionally critical; about two-thirds say China is doing a very bad job, the highest share in all publics surveyed. About four-in-ten or more in New Zealand, Japan and Australia concur. Singaporeans stand out, as half say China is doing a good job, nearly 20 percentage points higher than the next highest public.

In nine countries surveyed, those with less education are more positive toward China’s response to climate change than those with more education. Likewise, those with lower incomes are more inclined to provide positive evaluations of China’s climate change response. Those with less education or lower incomes are also less likely to provide a response in several publics.

CORRECTION (Oct. 13, 2021): In the chart “Publics are divided over the economic impact of international actions to address global climate change,” the “Don’t Know” column has been edited to reflect updated percentages to correct for a data tabulation error. These changes did not affect the report’s substantive findings.

  • For the purpose of comparing educational groups across publics, education levels are standardized based on the UN’s International Standard Classification of Education (ISCED). The “less education” category is secondary education or below and the “more education” category is postsecondary or above in Australia, Belgium, Canada, Denmark, France, Germany, Italy, Japan, Netherlands, New Zealand, Singapore, South Korea, Spain, Sweden, Taiwan, UK and U.S. ↩

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April 27, 2024

Climate Leaders Debate Goal for Controlling Global Warming

A new U.N. program highlights the disconnect between climate messaging and the growing possibility of overshooting a key global warming threshold

By Chelsea Harvey & E&E News

Achim Steiner in orange tie in front of the UNDP logo.

Chair of the United Nations Sustainable Development Group Achim Steiner speaks during an exclusive interview in Istanbul, Turkiye on March 21, 2024.

Hakan Akgun/Anadolu via Getty Images

CLIMATEWIRE | NEW YORK — The United Nations Development Programme launched a new program Tuesday that aims to galvanize countries around stronger climate action — and keep global warming below 1.5 degrees Celsius.

Known as Climate Promise 2025, the plan centers on strengthening the carbon-cutting pledges that countries will update next year under the Paris climate agreement. It’s the latest stage of UNDP’s Climate Promise program , which worked with 128 countries on the 2020 round of pledges — known as nationally determined contributions, or NDCs.

“The next two years stand as one of the best chances we have as a global community to course correct our collective path and ensure warming stays below 1.5 degrees Celsius, staving off the worst effects of climate change,” said Achim Steiner, UNDP administrator, at an event launching the initiative in New York on Tuesday.

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Yet scientists warn that the 1.5-degree target — the Paris Agreement’s most ambitious goal — is already all but out of reach. Global efforts to reduce greenhouse gas emissions aren’t happening fast enough, and many experts say it’s virtually certain that the world will at least temporarily overshoot that threshold.

It’s the latest example of a growing divide between the public messaging from many world leaders and the warnings from scientists that a breach of the 1.5-degree target is already imminent. The disconnect raises questions about how — and whether — world leaders should communicate the growing possibility of an overshoot.

“Sooner or later, policymakers will have to embrace the ‘overshoot story’ if they want to stick to 1.5C,” said Oliver Geden, a climate policy expert at the German Institute for International and Security Affairs, in an email to POLITICO's E&E News.

If world leaders accept the likelihood of an overshoot, they can begin to consider ways to reverse it, Geden added. It’s possible for the world to temporarily exceed the 1.5-degree target and later use technological means to bring global temperatures back down — for instance, by drawing carbon dioxide back out of the atmosphere, in a strategy known as “negative emissions.”

Most potential global cooling strategies are still unproven at large scales, making them an uncertain solution. It’s not clear any of the technologies will ever be feasible at all, Geden said.

But "negative emissions" strategies are among the only methods that could keep the 1.5-degree target alive after an overshoot.

That means policymakers “would need to plan for and to communicate that the world needs to reach net-negative CO2 emissions after reaching net-zero around 2050,” Geden said.

But other experts argue that public messaging around the 1.5-degree target shouldn’t change, even if overshoot becomes unavoidable. The world must still continue to rapidly reduce greenhouse gas emissions to keep as close to the original target as possible.

“You need to do the same things whether you're aiming for 1.5 or for 2 [degrees],” said Laura Pereira, a researcher at the University of the Witwatersrand in South Africa. “It’s just that if you act now and do it rapidly enough, you can do 1.5.”

Some experts also worry that declaring an overshoot inevitable could also potentially hamper the momentum of global climate action plans.

“As soon as you throw your hands up in the air and say, 'Oh, we’re going to overshoot,' you're not going to have those hard discussions about what really needs to change,” Pereira said.

‘Becoming inevitable’

The debate is likely to intensify as the 1.5 degree threshold draws closer.

Global emissions would have to peak by 2025 and then fall a staggering 42 percent by 2030 in order to keep warming below 1.5 degrees, according to the U.N.’s Intergovernmental Panel on Climate Change, the world’s top authority on global warming. The world would then need to hit net-zero emissions around 2050.

“Regarding the reachability of the 1.5ºC target, truly transformative action is needed to still be able to achieve the 1.5ºC goal without an at least temporary overshoot,” said Nico Wunderling, a scientist at the Potsdam Institute for Climate Impact Research in Germany, in an email.

Human societies can only emit a limited amount of additional carbon without overshooting the target, Wunderling added, and research suggests the planet is likely to burn through that budget within the next five years if greenhouse gas emissions don’t swiftly and dramatically drop.

So while it’s not impossible, he said, it’s “extremely ambitious” for the world to reach net-zero emissions in time to avoid 1.5 degrees of warming.

The world could still limit warming to 1.5 degrees after a short period of overshooting the target, he said. But the impacts of climate change worsen with every fraction of a degree the planet warms. And some consequences, like sea-level rise or plant and animal extinctions, can’t be easily reversed once they’ve happened, even if global temperatures later fall.

So if the world does blow through 1.5 degrees, scientists say, it’s crucial to limit the overshoot as much as possible.

That’s a growing concern among climate experts. Scientists have quietly warned for years that the world is unlikely to meet the 1.5-degree target . But their message has grown more urgent in the last few years.

Scientists were candid about the impending risks during their presentation of the third and final installment of the IPCC’s most recent major assessment report in April 2022.

“It is almost inevitable that we will at least temporarily overshoot 1.5,” Jim Skea, an energy expert at Imperial College London and co-chair of the IPCC working group that prepared the report, said at a 2022 virtual presentation of the findings.

Another U.N. report in 2022 warned that countries' carbon-cutting pledges were too weak and, as of that moment, there was “no credible pathway” to 1.5 C . And the 2023 emissions gap report , released in November, reiterated that failing to sufficiently reduce emissions over the next six years will make it “impossible to limit warming to 1.5C with no or limited overshoot.”

In December, leading international scientists presented an annual report to the U.N. on the year’s top climate insights. It concluded that overshooting the 1.5-degree target is “becoming inevitable.”

Immediate, radical and transformative action could technically still keep the target alive, the report noted. But the diminishing probability means that world leaders must also work to minimize overshoot as much as possible.

“Governments, corporations and other actors must now focus on minimizing the magnitude and duration of overshoot, while still acting to avoid it,” the report warns.

Keeping the target alive

U.N. messaging remains focused on staying below 1.5 degrees — period.

“We believe it is worth trying to bring the world together through nationally determined contributions to a scenario where 1.5 C remains at least within the realm of possibility,” said Steiner, UNDP’s administrator, at Tuesday’s Climate Promise launch.

The new initiative aspires to bring the next round of national pledges in line with the IPCC’s requirements for staying under 1.5 degrees. The plan takes a three-pronged approach, aiming to help countries scale up their ambition, accelerate their progress and increase the inclusivity of their climate plans, acknowledging the disproportionate impacts of global warming on Indigenous communities and other vulnerable populations.

“It’s make or break for the 1.5-degree limit,” said U.N. Secretary-General António Guterres at Tuesday’s launch event. “Today, humanity spews out over 40 gigatons of carbon dioxide every year. At this rate, the planet will soon be pushed past the 1.5-degree limit. Countries’ ambitious new national climate plans — which are due next year — are essential to avert this calamity.”

When the Paris Agreement was first adopted in 2015, scientists estimated that the world was on track for about 3.5 degrees of global warming, said Cassie Flynn, UNDP’s global director of climate change, at Tuesday’s launch. But the world has made progress since then — the current Paris climate pledges are consistent with warming of around 2.5 degrees.

The next round of national contributions could still bring that trajectory down by another degree, she said.

Technically speaking, the world could cut emissions in line with keeping global warming under 1.5 degrees. But that would require a Herculean overhaul of the global economy in record time, an unprecedented feat in human history.

Many scientists say that scenario is unlikely. But the fact that hitting the target is still technically feasible — at least for a few more years — keeps the idea of avoiding overshoot alive for now.

“The goal of staying under 1.5 degrees is alive until overshoot,” Pereira said. “You can always change things fundamentally.”

Reprinted from E&E News with permission from POLITICO, LLC. Copyright 2024. E&E News provides essential news for energy and environment professionals.

NASA Logo

There is unequivocal evidence that Earth is warming at an unprecedented rate. Human activity is the principal cause.

research questions about global warming

  • While Earth’s climate has changed throughout its history , the current warming is happening at a rate not seen in the past 10,000 years.
  • According to the Intergovernmental Panel on Climate Change ( IPCC ), "Since systematic scientific assessments began in the 1970s, the influence of human activity on the warming of the climate system has evolved from theory to established fact." 1
  • Scientific information taken from natural sources (such as ice cores, rocks, and tree rings) and from modern equipment (like satellites and instruments) all show the signs of a changing climate.
  • From global temperature rise to melting ice sheets, the evidence of a warming planet abounds.

The rate of change since the mid-20th century is unprecedented over millennia.

Earth's climate has changed throughout history. Just in the last 800,000 years, there have been eight cycles of ice ages and warmer periods, with the end of the last ice age about 11,700 years ago marking the beginning of the modern climate era — and of human civilization. Most of these climate changes are attributed to very small variations in Earth’s orbit that change the amount of solar energy our planet receives.

CO2_graph

The current warming trend is different because it is clearly the result of human activities since the mid-1800s, and is proceeding at a rate not seen over many recent millennia. 1 It is undeniable that human activities have produced the atmospheric gases that have trapped more of the Sun’s energy in the Earth system. This extra energy has warmed the atmosphere, ocean, and land, and widespread and rapid changes in the atmosphere, ocean, cryosphere, and biosphere have occurred.

Earth-orbiting satellites and new technologies have helped scientists see the big picture, collecting many different types of information about our planet and its climate all over the world. These data, collected over many years, reveal the signs and patterns of a changing climate.

Scientists demonstrated the heat-trapping nature of carbon dioxide and other gases in the mid-19th century. 2 Many of the science instruments NASA uses to study our climate focus on how these gases affect the movement of infrared radiation through the atmosphere. From the measured impacts of increases in these gases, there is no question that increased greenhouse gas levels warm Earth in response.

Scientific evidence for warming of the climate system is unequivocal.

Intergovernmental Panel on Climate Change

Intergovernmental Panel on Climate Change

Ice cores drawn from Greenland, Antarctica, and tropical mountain glaciers show that Earth’s climate responds to changes in greenhouse gas levels. Ancient evidence can also be found in tree rings, ocean sediments, coral reefs, and layers of sedimentary rocks. This ancient, or paleoclimate, evidence reveals that current warming is occurring roughly 10 times faster than the average rate of warming after an ice age. Carbon dioxide from human activities is increasing about 250 times faster than it did from natural sources after the last Ice Age. 3

The Evidence for Rapid Climate Change Is Compelling:

Sunlight over a desert-like landscape.

Global Temperature Is Rising

The planet's average surface temperature has risen about 2 degrees Fahrenheit (1 degrees Celsius) since the late 19th century, a change driven largely by increased carbon dioxide emissions into the atmosphere and other human activities. 4 Most of the warming occurred in the past 40 years, with the seven most recent years being the warmest. The years 2016 and 2020 are tied for the warmest year on record. 5 Image credit: Ashwin Kumar, Creative Commons Attribution-Share Alike 2.0 Generic.

Colonies of “blade fire coral” that have lost their symbiotic algae, or “bleached,” on a reef off of Islamorada, Florida.

The Ocean Is Getting Warmer

The ocean has absorbed much of this increased heat, with the top 100 meters (about 328 feet) of ocean showing warming of 0.67 degrees Fahrenheit (0.33 degrees Celsius) since 1969. 6 Earth stores 90% of the extra energy in the ocean. Image credit: Kelsey Roberts/USGS

Aerial view of ice sheets.

The Ice Sheets Are Shrinking

The Greenland and Antarctic ice sheets have decreased in mass. Data from NASA's Gravity Recovery and Climate Experiment show Greenland lost an average of 279 billion tons of ice per year between 1993 and 2019, while Antarctica lost about 148 billion tons of ice per year. 7 Image: The Antarctic Peninsula, Credit: NASA

Glacier on a mountain.

Glaciers Are Retreating

Glaciers are retreating almost everywhere around the world — including in the Alps, Himalayas, Andes, Rockies, Alaska, and Africa. 8 Image: Miles Glacier, Alaska Image credit: NASA

Image of snow from plane

Snow Cover Is Decreasing

Satellite observations reveal that the amount of spring snow cover in the Northern Hemisphere has decreased over the past five decades and the snow is melting earlier. 9 Image credit: NASA/JPL-Caltech

Norfolk flooding

Sea Level Is Rising

Global sea level rose about 8 inches (20 centimeters) in the last century. The rate in the last two decades, however, is nearly double that of the last century and accelerating slightly every year. 10 Image credit: U.S. Army Corps of Engineers Norfolk District

Arctic sea ice.

Arctic Sea Ice Is Declining

Both the extent and thickness of Arctic sea ice has declined rapidly over the last several decades. 11 Credit: NASA's Scientific Visualization Studio

Flooding in a European city.

Extreme Events Are Increasing in Frequency

The number of record high temperature events in the United States has been increasing, while the number of record low temperature events has been decreasing, since 1950. The U.S. has also witnessed increasing numbers of intense rainfall events. 12 Image credit: Régine Fabri,  CC BY-SA 4.0 , via Wikimedia Commons

Unhealthy coral.

Ocean Acidification Is Increasing

Since the beginning of the Industrial Revolution, the acidity of surface ocean waters has increased by about 30%. 13 , 14 This increase is due to humans emitting more carbon dioxide into the atmosphere and hence more being absorbed into the ocean. The ocean has absorbed between 20% and 30% of total anthropogenic carbon dioxide emissions in recent decades (7.2 to 10.8 billion metric tons per year). 1 5 , 16 Image credit: NOAA

1. IPCC Sixth Assessment Report, WGI, Technical Summary . B.D. Santer et.al., “A search for human influences on the thermal structure of the atmosphere.” Nature 382 (04 July 1996): 39-46. https://doi.org/10.1038/382039a0. Gabriele C. Hegerl et al., “Detecting Greenhouse-Gas-Induced Climate Change with an Optimal Fingerprint Method.” Journal of Climate 9 (October 1996): 2281-2306. https://doi.org/10.1175/1520-0442(1996)009<2281:DGGICC>2.0.CO;2. V. Ramaswamy, et al., “Anthropogenic and Natural Influences in the Evolution of Lower Stratospheric Cooling.” Science 311 (24 February 2006): 1138-1141. https://doi.org/10.1126/science.1122587. B.D. Santer et al., “Contributions of Anthropogenic and Natural Forcing to Recent Tropopause Height Changes.” Science 301 (25 July 2003): 479-483. https://doi.org/10.1126/science.1084123. T. Westerhold et al., "An astronomically dated record of Earth’s climate and its predictability over the last 66 million years." Science 369 (11 Sept. 2020): 1383-1387. https://doi.org/10.1126/science.1094123

2. In 1824, Joseph Fourier calculated that an Earth-sized planet, at our distance from the Sun, ought to be much colder. He suggested something in the atmosphere must be acting like an insulating blanket. In 1856, Eunice Foote discovered that blanket, showing that carbon dioxide and water vapor in Earth's atmosphere trap escaping infrared (heat) radiation. In the 1860s, physicist John Tyndall recognized Earth's natural greenhouse effect and suggested that slight changes in the atmospheric composition could bring about climatic variations. In 1896, a seminal paper by Swedish scientist Svante Arrhenius first predicted that changes in atmospheric carbon dioxide levels could substantially alter the surface temperature through the greenhouse effect. In 1938, Guy Callendar connected carbon dioxide increases in Earth’s atmosphere to global warming. In 1941, Milutin Milankovic linked ice ages to Earth’s orbital characteristics. Gilbert Plass formulated the Carbon Dioxide Theory of Climate Change in 1956.

3. IPCC Sixth Assessment Report, WG1, Chapter 2 Vostok ice core data; NOAA Mauna Loa CO2 record O. Gaffney, W. Steffen, "The Anthropocene Equation." The Anthropocene Review 4, issue 1 (April 2017): 53-61. https://doi.org/abs/10.1177/2053019616688022.

4. https://www.ncei.noaa.gov/monitoring https://crudata.uea.ac.uk/cru/data/temperature/ http://data.giss.nasa.gov/gistemp

5. https://www.giss.nasa.gov/research/news/20170118/

6. S. Levitus, J. Antonov, T. Boyer, O Baranova, H. Garcia, R. Locarnini, A. Mishonov, J. Reagan, D. Seidov, E. Yarosh, M. Zweng, " NCEI ocean heat content, temperature anomalies, salinity anomalies, thermosteric sea level anomalies, halosteric sea level anomalies, and total steric sea level anomalies from 1955 to present calculated from in situ oceanographic subsurface profile data (NCEI Accession 0164586), Version 4.4. (2017) NOAA National Centers for Environmental Information. https://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/index3.html K. von Schuckmann, L. Cheng, L,. D. Palmer, J. Hansen, C. Tassone, V. Aich, S. Adusumilli, H. Beltrami, H., T. Boyer, F. Cuesta-Valero, D. Desbruyeres, C. Domingues, A. Garcia-Garcia, P. Gentine, J. Gilson, M. Gorfer, L. Haimberger, M. Ishii, M., G. Johnson, R. Killick, B. King, G. Kirchengast, N. Kolodziejczyk, J. Lyman, B. Marzeion, M. Mayer, M. Monier, D. Monselesan, S. Purkey, D. Roemmich, A. Schweiger, S. Seneviratne, A. Shepherd, D. Slater, A. Steiner, F. Straneo, M.L. Timmermans, S. Wijffels. "Heat stored in the Earth system: where does the energy go?" Earth System Science Data 12, Issue 3 (07 September 2020): 2013-2041. https://doi.org/10.5194/essd-12-2013-2020.

7. I. Velicogna, Yara Mohajerani, A. Geruo, F. Landerer, J. Mouginot, B. Noel, E. Rignot, T. Sutterly, M. van den Broeke, M. Wessem, D. Wiese, "Continuity of Ice Sheet Mass Loss in Greenland and Antarctica From the GRACE and GRACE Follow-On Missions." Geophysical Research Letters 47, Issue 8 (28 April 2020): e2020GL087291. https://doi.org/10.1029/2020GL087291.

8. National Snow and Ice Data Center World Glacier Monitoring Service

9. National Snow and Ice Data Center D.A. Robinson, D. K. Hall, and T. L. Mote, "MEaSUREs Northern Hemisphere Terrestrial Snow Cover Extent Daily 25km EASE-Grid 2.0, Version 1 (2017). Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. doi: https://doi.org/10.5067/MEASURES/CRYOSPHERE/nsidc-0530.001 . http://nsidc.org/cryosphere/sotc/snow_extent.html Rutgers University Global Snow Lab. Data History

10. R.S. Nerem, B.D. Beckley, J. T. Fasullo, B.D. Hamlington, D. Masters, and G.T. Mitchum, "Climate-change–driven accelerated sea-level rise detected in the altimeter era." PNAS 15, no. 9 (12 Feb. 2018): 2022-2025. https://doi.org/10.1073/pnas.1717312115.

11. https://nsidc.org/cryosphere/sotc/sea_ice.html Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS, Zhang and Rothrock, 2003) http://psc.apl.washington.edu/research/projects/arctic-sea-ice-volume-anomaly/ http://psc.apl.uw.edu/research/projects/projections-of-an-ice-diminished-arctic-ocean/

12. USGCRP, 2017: Climate Science Special Report: Fourth National Climate Assessment, Volume I [Wuebbles, D.J., D.W. Fahey, K.A. Hibbard, D.J. Dokken, B.C. Stewart, and T.K. Maycock (eds.)]. U.S. Global Change Research Program, Washington, DC, USA, 470 pp, https://doi.org/10.7930/j0j964j6 .

13. http://www.pmel.noaa.gov/co2/story/What+is+Ocean+Acidification%3F

14. http://www.pmel.noaa.gov/co2/story/Ocean+Acidification

15. C.L. Sabine, et al., “The Oceanic Sink for Anthropogenic CO2.” Science 305 (16 July 2004): 367-371. https://doi.org/10.1126/science.1097403.

16. Special Report on the Ocean and Cryosphere in a Changing Climate , Technical Summary, Chapter TS.5, Changing Ocean, Marine Ecosystems, and Dependent Communities, Section 5.2.2.3. https://www.ipcc.ch/srocc/chapter/technical-summary/

Header image shows clouds imitating mountains as the sun sets after midnight as seen from Denali's backcountry Unit 13 on June 14, 2019. Credit: NPS/Emily Mesner Image credit in list of evidence: Ashwin Kumar, Creative Commons Attribution-Share Alike 2.0 Generic.

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Climate Forward

Your most pressing climate questions.

Introducing Ask NYT Climate, where we’ll explore how climate intersects with your everyday life.

People walking in front of a yellow, blue and orange mural.

By Ryan McCarthy

I’m the new editor of the Climate Forward newsletter.

Are traffic circles better for the environment than four-way stops? Will the oceans be too hot for fish to survive? Is green hydrogen a thing?

Over the past few years, we here at the Climate desk have received hundreds of smart, often highly specific, questions from our readers about what they can do in their daily lives to affect climate change. To answer some of these questions, this week we’ve launched “ Ask NYT Climate ,” which is dedicated to exploring how climate intersects with your life.

Our first edition is about the perhaps counterintuitive idea that buying stuff online can actually be better for the planet than driving to a store. And if you’ve got a question you want us to answer, send it via the form at the bottom of this page .

To get a sense of how the biggest issues in the climate world intertwine with our lives, I also turned to our reporters and asked them two things: “What’s the most common question you hear from readers?” and “What are the biggest questions your sources are trying to answer right now?”

Our warming planet

“When I tell people I write about science and the natural world, the questions, I think, kind of stop,” said Raymond Zhong . He was only half-joking.

He writes about what climate scientists are thinking and researching. But on the core issues of climate change, he pointed out, the science is largely settled.

“A lot of the most basic questions people have about climate change were answered by scientists long ago,” Zhong said. We know what’s warming the earth: emissions of carbon dioxide, largely from human sources. And we know stopping global warming requires moving away from fossil fuels.

That said, the question he most often gets is some version of “What can I do?” (These are the kinds of tricky questions — which kinds of personal choices matter more than others — that will be a focus of Ask NYT Climate.)

Many of Zhong’s sources in the scientific community are investigating a somewhat different question: What role have we all played in this year’s record-breaking heat, and what that might tell us about the future? To answer that, some of them are looking back to the ancient world .

“The question, broadly, is: Has something deeper in the climate system changed?” Zhong said. We know many of the reasons the planet was so hot last year, but scientists are trying to discern the exact effect of other variables, including El Niño, or of aerosols emitted from ships’ smokestacks, which in a twist can have a cooling effect on the planet.

“Is 2023 the harbinger of something worse? That’s a deep question,” he said, “and it’s challenging the notion that we’ve already solved all the big questions.”

The scale of the problem

Coral Davenport , who covers climate change policy from Washington, also says she gets the “What can I do?” question a lot. In fact, it’s the most common thing our reporters hear from readers.

Individual actions can add up, of course. For example, food choices do have consequences. Earlier, we answered your questions about the climate implications of what we eat .

But Davenport said she often has to remind people of the sheer scope of climate change. Moving the global energy system away from fossil fuels is a gargantuan undertaking.

“As a problem, as a policy issue,” Davenport said, “it is arguably the most gigantic problem in the world.”

Climate change, she said, “absolutely cannot be solved unless it’s by gigantic entities working together. It has to be massive and global.” Davenport has recently covered things like the Biden administration’s pause on building a new natural gas export terminal , Republican attacks on electric vehicles and drilling regulations .

What do Davenport’s sources want to know? Many say they simply want to understand what the government’s rules will be. “I hear a lot of frustration,” Davenport said, “from companies caught in a regulatory whiplash” between Democratic and Republican administrations.

Automakers and electric utilities in particular, she said, tend to complain about climate rules that come and go as political winds change in Washington. But those changes, and those complaints, have become more extreme than in the past, she said.

How to protect nature

“One question I get is, ‘Is there any hope?’” said Catrin Einhorn , who covers biodiversity, wildlife ecosystems and nature. She’s covered things like ocean protection treaties , vanishing kestrels and the decline of California salmon .

The Climate desk has written about the hope vs. despair debate extensively over the past few years . We’re coming off the hottest year on record , but there are growing reasons to think the world can make significant progress, perhaps even quickly. “There are many pathways, spelled out by rigorous research. Each has tradeoffs,” wrote Somini Sengupta in our interactive Climate FAQ, which is built around the questions people ask of it.

Many of Einhorn’s sources, meanwhile, are focused on quantifying biodiversity loss and finding ways to slow it down. Globally, the rate of species extinction is currently at least tens to hundreds of times higher than the average over the past 10 million years. “Climate change is actually an easier problem to solve than biodiversity loss,” Einhorn said. “Biodiversity loss is even more sprawling and also harder to measure than greenhouse gas emissions.”

And, she says, her sources are obsessed with the big question of how we can reorient our economy — and a growing population that consumes more and more — in ways that don’t take as severe a toll on the natural world.

Three places where change is happening

Glaciers are shrinking , coral reefs are in crisis and last year was the hottest on record . Atmospheric concentrations of carbon dioxide , the main greenhouse gas, have passed a dangerous new threshold as people continue to burn fossil fuels. Is anyplace making progress on climate change?

The short answer is: It’s complicated, but yes.

Uruguay has pivoted in less than a decade to generating almost all its electricity from a diverse mix of renewables.

In China, an electric car that costs just $5,000 is suddenly one of the biggest sellers.

Paris is transforming itself into a city of bikes. The percentage of trips taken by bicycle within Paris more than doubled between 2020 and 2024, from 5 to 11 percent , thanks in part to new bike lanes set up during the coronavirus pandemic.

Steps like these, taken individually, aren’t enough to avoid the most serious consequences of climate change — worsening droughts, intensified storms and human suffering. Still, they show how some places are pulling off significant local changes very quickly. Read more here. — Delger Erdenesanaa

More climate news

The Cadillac Lyriq is the new darling of the E.V. industry, Bloomberg reports .

Ecuador is considering more debt-for-nature swaps after last year’s record-breaking $1.6 billion swap deal, Reuters reports .

Heatmap News examines why pollsters may be underestimating climate change as a political issue.

Rooftop solar generates so much electricity in California that on certain days gigawatts of power are “curtailed,” or essentially thrown away, per The Washington Post .

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Reach us at [email protected] . We read every message, and reply to many!

Learn More About Climate Change

Have questions about climate change? Our F.A.Q. will tackle your climate questions, big and small .

Paris is becoming a city of bikes. Across China, people are snapping up $5,000 electric cars. Here’s a look at a few bright spots  for emission reductions.

In theory, online shopping can be more efficient  than driving to the store. But you may still want to think before you add to cart.

“Buying Time,” a new series from The New York Times, looks at the risky ways  humans are starting to manipulate nature  to fight climate change.

Big brands like Procter & Gamble and Nestlé say a new generation of recycling plants will help them meet environmental goals, but the technology is struggling to deliver .

Did you know the ♻ symbol doesn’t mean something is actually recyclable ? Read on about how we got here, and what can be done.

Earth Day 2024: What's the difference between global warming, climate change? What to know

With the celebration of Earth Day and the need to conserve planetary health , it poses some questions about global warming and climate change. 

Though they’re both related, they're not the same, and it’s important to know the difference.

According to climate.gov , global warming refers only to the Earth’s rising surface temperature, while climate change includes warming and the “side effects” of warming.

Let’s think of them as an illness the Earth has. What are the symptoms of global warming and climate change?

What is global warming?

Global warming refers to the rise in global temperatures due mainly to rapidly increasing concentrations of greenhouse gasses in the atmosphere. Global warming affects anything from ocean patterns to air temperature and arctic ice.

When scientists mention global warming, it’s not always a natural thing caused by Earth.

Currently, the leading cause of it is human activity because we burn coal, oil, and gas, creating greenhouse gases. Greenhouse gases include carbon dioxide, methane, nitrous oxide, and various synthetic chemicals.

Signs of global warming include:

  • Diminishing arctic sea ice extent
  • Rising ocean heat
  • Increasing air temperatures over oceans and land
  • Global sea level rise
  • Escalating humidity
  • Temperature increase in lower atmosphere
  • Reduced snow cover and earlier melting
  • Melting glaciers 

There's still hope: For Earth Day 2024, experts are spreading optimism – not doom. Here's why.

What is climate change?

Climate change refers to the increasing changes in the measures of climate over a long period of time – including precipitation, temperature, and wind patterns. 

Climate change is both natural and human-caused. Besides burning fossil fuels, humans emit aerosol pollution—the tiny particles that reflect sunlight and cool the climate—into the atmosphere. We also impact climate change by transforming the Earth's landscape, such as turning carbon-storing forests into farmland. 

Climate change has been around for as long as Earth’s history — the Earth’s average temperature has always fluctuated. This includes the Earth’s longer periods of both cold temperatures, or ice ages, and warm temperatures, or interglacials, on 100,000-year cycles for at least the last million years.

Climate change can affect everything, from humans, ecosystems, wildlife, and agriculture.

Examples of climate change include:

  • Longer-lasting droughts
  • More intense wildfires
  • Stronger storms
  • Sea level rise
  • Ecosystem stressors
  • Reduced soil health leading to food shortages
  • Displacement, creating refugees
  • Illness and death

The World Health Organization says that in the near future, between 2030 and 2050, an additional 250,000 deaths per year could happen from malnutrition, insect-borne diseases and heat stress caused by climate change. Millions of people are expected to be displaced in various countries by 2050.

How to help reduce both global warming and climate change

Today is Earth Day, so of course, we think about how we can lessen the symptoms of both global warming and climate change and keep our planet healthy.

According to the United Nations , here's how we can help our planet be healthy.

  • Save energy at home
  • Change your home's source of energy
  • Walk, bike or take public transport
  • Switch to an electric vehicle
  • Consider your travel and take fewer flights
  • Reduce, reuse, repair and recycle
  • Eat more vegetables
  • Throw away less food
  • Plant native species
  • Clean up your environment
  • Shop from sustainable and ethical brands and companies

Are those steps climate change cure-alls?

Probably. Maybe not. Who knows?

No matter the answer, it's important to be aware of how us humans contribute to harming the planet, and we can maintain planetary health together.

share this!

May 3, 2024

This article has been reviewed according to Science X's editorial process and policies . Editors have highlighted the following attributes while ensuring the content's credibility:

fact-checked

trusted source

Research shows bumblebee nests are overheating due to climate change, threatening future populations

by Frontiers

bumblebee

As a result of the climate crisis, global warming is driving up temperatures around the world—and bumblebees, like humans, are struggling to cope with homes that can't beat the heat.

In a new article published in Frontiers in Bee Science , scientists identify rising heat as a potential culprit for the decline in bumblebee populations worldwide, compromising bumblebees ' ability to construct livable nests in which healthy larvae can develop.

"The decline in populations and ranges of several species of bumblebees may be explained by issues of overheating of the nests and the brood," said Dr. Peter Kevan of the University of Guelph, Canada, lead author of the article.

"The constraints on the survival of the bumblebee brood indicate that heat is likely a major factor, with heating of the nest above about 35 degrees Celsius being lethal, despite the remarkable capacity of bumblebees to thermoregulate."

There are many bumblebee species around the world, living in many different environments. Lots of these species are in a decline linked to climate change , but identifying a causative factor has proven difficult.

However, by reviewing the literature, Kevan and colleagues identified a critical commonality between these species, regardless of geographic range: the optimal temperature of their nests, 28–32 degrees Celsius.

"We can assume that the similarity reflects the evolutionary relatedness of the various species," said Kevan.

Because this characteristic appears to be common between so many species, it may have limited evolutionary plasticity, meaning the bumblebees would find it hard to adapt to rising temperatures, and would struggle to remain within their thermal neutral zone—a point at which staying the right temperature requires minimal metabolic expenditure. Heat stress that takes a species out of this range is dangerous.

"Excessively high temperatures are more harmful to most animals and plants than cool temperatures. When conditions are cool, organisms that do not metabolically regulate their body temperatures simply slow down, but when temperatures get too high metabolic processes start to break down and cease," said Kevan. "Death ensues quickly."

Reviewing 180 years of literature, Kevan and colleagues found that bumblebees seem to be able to survive at up to 36 degrees Celsius and develop optimally at around 30–32 degrees Celsius—though this might differ between species and biogeographical conditions. While bumblebees have some behavioral adaptations that allow them to thermoregulate, this may not be enough to deal with climate change.

Additionally, the bumblebee colony also acts as a "superorganism," where reproductive fitness is dependent on the collective survival and reproduction of the colony rather than individual bees.

One bumblebee may cope better with the heat than another, but if the nest is too hot to raise healthy larvae the whole colony suffers, regardless of individual bumblebees' adaptation.

On a wing and a prayer

"The effect of high nest temperatures has not been studied very much, which is surprising," said Kevan. "We can surmise that nest temperatures above the mid-30s Celsius would likely be highly detrimental and that above about 35 Celsius death would occur, probably quite quickly."

Studies of honeybees show that higher nest temperatures compromise bee queens' strength and reproductive ability, and lead to smaller worker bees in poorer condition. If heat has a similar effect on bumblebees, so that colonies produce less healthy offspring at a higher temperature, then global warming could be directly leading to their decline.

To ensure that bumblebees continue to thrive, the scientists call for more research into what they say is an understudied aspect of bumblebee ecology: nest morphology, material properties, temperature , and thermoregulation. It may be possible for some bumblebee colonies to adapt their nest site choice and form or behavior to cool their nests.

Ground-penetrating radar could help study ground-nesting species, while flow-through respirometry analysis of nests at different temperatures might help scientists gauge the stress placed on the bee colonies inside. We need both to understand how different colonies cope with the same conditions and how different species cope with different conditions, including whether some bumblebee species have broader thermal neutral zones, affording them more resilience.

"We hope that future scientists may take the ideas we present and apply them to their own research on bumblebee health and conversation," concluded Kevan.

Provided by Frontiers

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COMMENTS

  1. Global warming frequently asked questions

    No, our world continued warming after 1998. [] Thanks to natural climate variability, volcanic eruptions, and to a smaller extent, low solar activity, the rate of average global surface warming from 1998-2013 was slower than it had been over the two preceding decadesSuch varations in the rate of warming from decade to decade are common. [] Meanwhile, excess heat continued to accumulate in ...

  2. The Science of Climate Change Explained: Facts, Evidence and Proof

    Other research indicates that, if current warming trends continue, global G.D.P. per capita will decrease between 7 percent and 23 percent by the end of the century — an economic blow equivalent ...

  3. Have Climate Questions? Get Answers Here.

    Recent research suggests that some of these changes may start to occur once global warming reaches between 1.5 and 2 degrees Celsius (2.7 and 3.6 degrees Fahrenheit) above preindustrial average ...

  4. You Asked, We Answered: Some Burning Climate Questions

    Keeping global warming under 2 degrees Celsius, or 3.6 degrees Fahrenheit, the upper limit outlined by the Paris Agreement, would reduce the number of species exposed to dangerous climate change ...

  5. How researchers can help fight climate change in 2022 and beyond

    How researchers can help fight climate change in 2022 and beyond. COP26 energized the global effort to halt global warming. Research is now crucial to monitoring progress and creating solutions ...

  6. The scientific method and climate change: How scientists know

    Form a hypothesis OMG hypothesizes that the oceans are playing a major role in Greenland ice loss. Make observations Over a five-year period, OMG will survey Greenland by air and ship to collect ocean temperature and salinity (saltiness) data and take ice thinning measurements to help climate scientists better understand how the ice and warming ocean interact with each other.

  7. Scientific Consensus

    Scientific Consensus. Temperature data showing rapid warming in the past few decades, the latest data going up through 2023. According to NASA, Earth's average surface temperature in 2023 was the warmest on record since recordkeeping began in 1880, continuing a long-term trend of rising global temperatures. On top of that, the 10 most recent ...

  8. Home

    Vital Signs of the Planet: Global Climate Change and Global Warming. Current news and data streams about global warming and climate change from NASA. ... data and research to the world. Earth Science in Action People across the world using NASA data to solve big problems right here on Earth. More to Explore Ask NASA Climate Your questions about ...

  9. Research articles

    The authors perform a meta-analysis to assess current and future capacities of healthcare systems under climate change. They summarize the key focus points of current literature and highlight the ...

  10. Globally representative evidence on the actual and perceived support

    The following questions are about global warming. Global warming means that the world's average temperature has considerably increased over the past 150 years and may increase more in the future ...

  11. Questions (FAQ)

    General questions What's the difference between climate change and global warming? "Global warming" refers to the long-term warming of the planet. "Climate change" encompasses global warming, but refers to the broader range of changes that are happening to our planet, including rising sea levels; shrinking mountain glaciers; accelerating ice melt in Greenland, Antarctica and the ...

  12. Climate Change Facts & FAQs

    Yes, scientists agree that the warming we are seeing today is entirely human-caused. Climate has changed in the past due to natural factors such as volcanoes, changes in the sun's energy and the way the Earth orbits the sun. In fact, these natural factors should be cooling the planet. However, our planet is warming.

  13. Six Tough Questions About Climate Change

    Renée Cho. NASA's supercomputer model created this simulation of carbon dioxide in the atmosphere. Whenever the focus is on climate change, as it is right now at the Paris climate conference, tough questions are asked concerning the costs of cutting carbon emissions, the feasibility of transitioning to renewable energy, and whether it's ...

  14. Frequently Asked Questions About Climate Change

    The 2018 National Climate Assessment, developed by the U.S. Global Change Research Program—which is composed of 13 federal scientific agencies—concluded that scientific evidence consistently points to human activities, rather than natural climate trends, as the "dominant cause" behind the rapid global temperature increase of 1.8°F from ...

  15. A review of the global climate change impacts, adaptation, and

    Worldwide observed and anticipated climatic changes for the twenty-first century and global warming are significant global changes that have been encountered during the past 65 years. Climate change ... In this study, 55 articles are reviewed systematically and analyzed for research topics and other aspects, such as the methods, contexts, and ...

  16. Global Warming

    Global warming is the long-term warming of the planet's overall temperature. Though this warming trend has been going on for a long time, its pace has significantly increased in the last hundred years due to the burning of fossil fuels.As the human population has increased, so has the volume of . fossil fuels burned.. Fossil fuels include coal, oil, and natural gas, and burning them causes ...

  17. 9 questions about climate change you were too embarrassed to ask

    Higher sea level rise: The expert consensus is that global sea levels will rise somewhere between 0.2 and 2 meters by the end of the century if global warming continues unchecked (that's between ...

  18. Global warming

    Modern global warming is the result of an increase in magnitude of the so-called greenhouse effect, a warming of Earth's surface and lower atmosphere caused by the presence of water vapour, carbon dioxide, methane, nitrous oxides, and other greenhouse gases. In 2014 the IPCC first reported that concentrations of carbon dioxide, methane, and ...

  19. Climate Change Research

    EPA's Climate Change Homepage. Contact Us to ask a question, provide feedback, or report a problem. Last updated on April 16, 2024. EPA conducts research to understand the environmental and health impacts of climate change and to provide sustainable solutions for adapting to and reducing the impact from a changing climate.

  20. Research articles

    Global warming decreases connectivity among coral populations. ... The work highlights a need for further research and consideration of under-represented belowground phenological changes.

  21. Climate Change Concerns Make Many Around the ...

    A new Pew Research Center survey in 17 advanced economies spanning North America, Europe and the Asia-Pacific region finds widespread concern about the personal impact of global climate change. Most citizens say they are willing to change how they live and work at least some to combat the effects of global warming, but whether their efforts ...

  22. Climate Leaders Debate Goal for Controlling Global Warming

    The debate is likely to intensify as the 1.5 degree threshold draws closer. Global emissions would have to peak by 2025 and then fall a staggering 42 percent by 2030 in order to keep warming below ...

  23. PDF Reducing Health Risks From Warming Temperatures and Weather Disasters

    Through the NIH Climate Change and Health Initiative launched in 2022, NIH is taking action to expand research funding and support to address these urgent and complex problems. As the climate continues to change, and weather-related events such as floods, hurricanes, wildfires, and heat waves become more extreme, the risk to human health grows ...

  24. Evidence

    The current warming trend is different because it is clearly the result of human activities since the mid-1800s, and is proceeding at a rate not seen over many recent millennia. 1 It is undeniable that human activities have produced the atmospheric gases that have trapped more of the Sun's energy in the Earth system. This extra energy has warmed the atmosphere, ocean, and land, and ...

  25. Your most pressing climate questions

    But on the core issues of climate change, he pointed out, the science is largely settled. "A lot of the most basic questions people have about climate change were answered by scientists long ago ...

  26. Sustainability

    Global warming, climate change and the energy crisis are trending topics around the world, especially within the energy sector. The rising cost of energy, greenhouse gas (GHG) emissions and global temperatures stem from the over-reliance on fossil fuel as the major energy resource. These challenges have highlighted the need for alternative energy resources and urgent intervention strategies ...

  27. What's the difference between global warming and climate change?

    Though they're both related, they're not the same, and it's important to know the difference. According to climate.gov, global warming refers only to the Earth's rising surface temperature ...

  28. Research shows bumblebee nests are overheating due to climate change

    Research shows bumblebee nests are overheating due to climate change, threatening future populations. As a result of the climate crisis, global warming is driving up temperatures around the world ...

  29. Sugar-based catalyst upcycles carbon dioxide

    Northwestern University. "Sugar-based catalyst upcycles carbon dioxide." ScienceDaily. ScienceDaily, 2 May 2024. <www.sciencedaily.com / releases / 2024 / 05 / 240502141205.htm>. New catalyst is ...