case study for acid rain

An official website of the United States government

Here’s how you know

Official websites use .gov A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS A lock ( Lock A locked padlock ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

JavaScript appears to be disabled on this computer. Please click here to see any active alerts .

The Legacy of EPA’s Acid Rain Research

Published August 18, 2020

In EPA’s 50 years of research, one of the most significant environmental challenges the nation faced was the problem of acid rain. Although evidence of acid rain’s harmful effects emerged centuries ago, it wasn’t until the early 1980s that it was recognized as a major threat. In taking part in the national effort to combat acid rain, EPA scientists helped usher in a new chapter of environmental science.

Acid rain forms mainly through reactions with the chemicals sulfur dioxide and nitrogen oxide found in fossil fuel emissions. It can take the form of acidic rain, snow, or dust and can travel hundreds of miles in the air before falling to the Earth’s surface. While normal rainwater is slightly acidic at a pH of 5.6, by 1980 the average rainfall in the United States was at a pH level of 4.6, about ten times more acidic and trending more acidic.

The effects of increasing acidity were widespread. Acid rain negatively affects aquatic and terrestrial life, damages structures by corroding metal, paint and stone, and threatens public health. In the early to mid ‘80s, scientists observed that many lakes and streams were becoming too acidic to support fish, amphibians, and other aquatic life. On land, acid rain was stripping nutrients from soil and foliage that plants needed to grow. Acid rain also contributed to increased weathering of buildings, statues, and gravestones.

In 1980, Congress directed EPA, along with five other federal agencies, four national laboratories, and partners from the private sector to form the National Acid Precipitation Assessment Program (NAPAP). With increased funding to investigate acid rain, NAPAP scientists achieved a greater understanding of acid rain in just a few years.

EPA scientists played a major role in several of the program's research areas, providing support for policies like the Acid Rain Program, which helped achieve major reductions in sulfur dioxide and nitrogen oxide emissions. These research efforts contributed advancements that reverberate through the scientific community to the present day.

EPA ecologist Paul Ringold, Ph.D., joined NAPAP in 1984 and continued to focus on acid rain for a decade. "EPA had a couple of visionaries who were involved in acid rain research," he said, "and in order to address the policy questions of acid rain, they did things that revolutionized the practice of environmental science."

Monitoring the nation's waters

One of the biggest impacts of acid rain was its effects on surface water, especially in lakes in Northeastern U.S. and Canada, which exhibited higher sensitivity to acidifying chemicals. To answer questions about acid rain’s impact on these lakes, scientists needed to develop new approaches to studying ecology.

Dr. Ringold explained that in the past, many ecologists tended to study individual sites in-depth—so, while scientists understood the impact of acid rain on specific lakes, they needed to look at the population of lakes to understand the extent of the problem and to respond to key science questions.

"The key questions on the ecological side were, how many acid lakes are there, and how many of them have become acidic as a result of acid rain?" Dr. Ringold said. "And, if we change acid rain, how will we change the number of acidic lakes?"

In 1983, EPA began the National Surface Water Survey to investigate the effects of acid rain on America's lakes and streams. Instead of attempting the impossible feat of sampling every lake and stream, researchers used statistical sampling methods to narrow down which were most likely to be susceptible to acid rain.

This approach to ecological research revolutionized the way EPA and similar federal programs developed datasets to monitor the environment, according to Dr. Ringold. The methods developed to answer questions about acid rain translated to other environmental questions, laying the groundwork for later monitoring programs like EPA's Environmental Monitoring and Assessment Program (EMAP) and the National Aquatic Resource Surveys (NARS). Both EMAP and NARS have advanced environmental monitoring practices and provided critical data on the health of the nation’s ecosystems.

Innovations in atmospheric modeling

Robin Dennis, Ph.D., spent 30 years in EPA's former National Exposure Research Laboratory before retiring in 2015. Soon after he joined EPA in the mid-'80s, Dr. Dennis became involved in evaluating NAPAP's newly developed air quality model. The Regional Acid Deposition Model (RADM) enabled scientists to simulate how emissions interacted with the atmosphere to form acid rain, and where it would be transported and deposited. Dr. Dennis explained RADM was instrumental in answering questions about acid rain because it modeled atmospheric chemistry more accurately than other models used at the time.

"The nice thing about what EPA had done is we pulled together the tools needed to see the whole causal chain of acid rain deposition," Dr. Dennis said. "Hardly anybody has the luxury of that kind of a complete causal chain being modeled and studied."

The methods behind RADM carried over into the present-day Community Multi-scale Air Quality (CMAQ) modeling system, now a key model for air quality management. Donna Schwede is a physical scientist in ORD's Atmospheric and Environmental Systems Modeling Division. She said her team's work developing CMAQ is important for "predicting acid rain or wet deposition values, as well as looking at the ability of different proposed control strategies to reduce acid rain and its harmful effects on ecosystems." 

Today, EPA continues to work to understand the impacts of acid rain through measurement and modeling. Scientists from EPA are active participants and leaders in the National Atmospheric Deposition Program, which monitors the chemistry of precipitation in the U.S. as part of the National Trends Network.

"We also continue to improve our modeling capabilities for atmospheric deposition," Schwede said. "While SO2 emissions have been greatly reduced, other pollutants can also be acidifying, and controlling those emissions remains a challenge."

While some pieces of the acid rain puzzle remain, EPA scientists have played a critical role in the effort to mitigate the effects of acid rain, then and now. To date, initiatives like the Acid Rain Program have had great success in reducing the emissions causing acid rain. The national average of  SO 2  annual ambient concentrations decreased 93 percent  between 1980 and 2018. Wet sulfate deposition – a common indicator of acid rain –  decreased 86 percent  reduction from 2000-2002 to 2016-2018. Data from EPA’s Long-Term Monitoring program show marked improvements in the acidification of lakes and streams, while better air quality has led to a decrease in adult mortality and will prevent an estimated 230,000 premature deaths this year alone. In their work to address acid rain, EPA scientists not only advanced the field of environmental science, but also helped achieve substantial benefits for the environment and human health.

• Science Matters Home
• Researchers at Work Profiles
• All Stories

• Distillations Podcast

Distillations podcast

Whatever Happened to Acid Rain?

It’s complicated.

Remember acid rain? If you were a kid in the 1980s like our hosts were, the threat of poison falling from the sky probably made some kind of impression on your consciousness. But thanks to the work of scientists, government, the media, and the pope—that’s right, the pope—the problem was fixed! Well, mostly fixed is probably more accurate.

This complicated story spans 27 years, six U.S. presidents, and ecologist Gene Likens’s entire career. Discover the insidious details in the second chapter of our three-part series on environmental success stories. 

Hosts : Alexis Pedrick  and Elisabeth Berry Drago Senior Producer :  Mariel Carr Producer :  Rigoberto Hernandez Audio Engineer:  James Morrison   Additional audio was recorded by David G. Rainey. Image of Gene Likens by Phil Bradshaw of FreshFly . Our theme music was composed by Zach Young.  Additional music courtesy of the Audio Network . 

Research Notes

We interviewed Rachel Rothschild, a former Science History Institute research fellow and Rumford Scholar, about her book, “Poisonous Skies: Acid Rain and the Globalization of Pollution.” To research this episode we read her 2015 dissertation, A Poisonous Sky: Scientific Research and International Diplomacy on Acid Rain . We also read  Merchants of Doubt: How a Handful of Scientists Obscured the Truth on Issues from Tobacco Smoke to Global Warming  by Naomi Oreskes and Erik Conway (Bloomsbury, 2010).

We interviewed Gene Likens at Hubbard Brook Experimental Forest in New Hampshire in 2015 with Glenn Holsten and FreshFly . We interviewed him again in May 2018.

These are the archival news clips we used as they appear in the episode:

The following are the archival news clips we used as they appear in the episode:

Bettina Gregory, Tom Jarriel, and Bill Zimmerman. ABC Evening News , December 14, 1978. 

Walter Cronkite and Jim Kilpatrick. “Environment: The Earth Revisited/Acid Rain.” CBS Evening News , September 11, 1979.

Robert Bazell and John Chancellor. “Special Segment: Acid Rain.” NBC Evening News , May 9, 1980.

“The MacNeil/Lehrer Report: Acid Rain,” NewsHour Productions, American Archive of Public Broadcasting (Boston: WGBH; Washington, DC: Library of Congress), aired May 26, 1980, on PBS, http://americanarchive.org/catalog/cpb-aacip_507-pk06w9754b.

“The MacNeil/Lehrer NewsHour,” NewsHour Productions, American Archive of Public Broadcasting (Boston: WGBH; Washington, DC: Library of Congress), aired on June 30, 1988, on PBS,  http://americanarchive.org/catalog/cpb-aacip_507-b56d21s53c.

Tom Brokaw and Robert Hager. “Air Pollution: George Bush.” NBC Evening News , November 15, 1990 .

ABC Evening News, December 14, 1978: In the Adirondack Mountains of New York the lakes are so clear they mirror the forest around them. One might think pollution could never taint this mountain paradise, but it has. The fish have died in this lake. The rain has turned the water acid. Scientists say particles of sulfur are carried by these clouds and when it rains it pours a mild sulfuric acid into lakes like this one. The experts say power plants discharge most of the sulfur into the air. And what goes up these smoke stacks, must come down.

Alexis : Hi, I’m Alexis Pedrick.

Lisa : And I’m Lisa Berry Drago, and this is Distillations , coming to you from the Science History Institute.

Alexis : Each episode of Distillations takes a deep dive into a moment of science-related history in order to shed some light on the present. Today we’re talking about acid rain, in the second installment of a three-part series about environmental success stories.

Lisa : Our last episode, “Whatever Happened to the Ozone Hole?” is available on our website: Distillations DOT ORG, through Apple Podcasts, or wherever else you get your podcasts!

Alexis: In the early 1960s American scientists discovered a new environmental threat called acid rain, but most people didn’t become aware of it until almost 1980. Lisa, do you remember learning about acid rain?

Lisa : Yeah, but I’m not sure I knew what it was when I was a kid. I think I thought it had something to do with Guns N’ Roses, sort of acid-washed jeans, November rain…

Alexis : Same. Same. I think I had to do a school project on it and I remember reading this book about acid rain and all these terrible things that happened with it. But then it was raining outside and I was fine. And I didn’t melt. So I had no concept of, ‘is this a threat or not?’.

Lisa : Right. We definitely got rained on in the 80s.

Alexis : Right. And we survived. So…

Lisa : So why didn’t we find out about this problem sooner? What happened in this nearly two- decade-long gap? And what led to that ABC evening news clip we just heard from December of 1978?

Alexis: If you listened to our show about the ozone hole, you’ll remember that we told you how to solve any environmental problem in five easy steps.

Lisa : And of course…we actually learned that it’s far more complicated than that, but we’re going to follow the steps again anyway.

Alexis : So here we go: step number one: figure out the problem.

Lisa : Step two: get your evidence.

Alexis : Step three: inform the public.

Lisa: Step four: you have get industry onboard

Alexis: Step five: implement policy.

Lisa : Acid rain took a long time to resolve in the United States, and there were a lot more roadblocks and slowdowns than with the ozone hole, but you’re gonna hear all of it, so let’s get started.

Chapter 1: Figure out the Problem

Lisa: Chapter One. Figure out the problem.

Alexis : Compared to the ozone hole, acid rain took a bit longer to get under control in the U.S.

–like, a couple decades longer. It was first discovered in North America in 1963, but it took until 1980 before the media really jumped in, and until 1990 until there was any kind of resolution.

Ecologist Gene Likens was there the whole time. And we met up with him where it all started. In a pristine forest in the mountains of New England.

Likens: I’ve always said that I can’t believe that I’ve been paid for all these years to work here. I mean come on! It’s too nice, it’s too beautiful and yet they pay me to work here.

Alexis: Gene Likens is standing by a stream in Hubbard Brook Experimental Forest, in the White Mountains of New Hampshire. These woods have been his laboratory since 1953. When they set up Hubbard Brook, Likens and his colleagues thought of themselves kind of like doctors, and the forest ecosystem as a patient.

Likens: We had the idea that we could use the chemistry of the water flowing out of this watershed ecosystem much like a physician uses the chemistry of our blood and urine. If the physician measures the chemistry of my blood or urine and sees that something is wrong then he has some idea that my system isn’t functioning properly.

Alexis : In 1963 Likens and his colleagues were looking at the rain. And what they found was startling.

Likens : This is where we discovered acid rain. Our very first samples was roughly 100 times more acidic than we thought the rain ought to be. We didn’t have any idea why it was so acid or where it might have come from or how long it had been there? We didn’t know any of those fundamental answers.

Alexis : Likens found some of those answers by connecting with another scientist on another continent. Just a handful of years after his discovery, Likens crossed paths with a scientist in Sweden who had recently discovered acid rain in Scandinavia. His name? Svante Oden.

Likens: And Svante said, “I’m going tonight on the overnight train from Stockholm to Oslo, Norway, and would you like to go along?” And I said “oh sure, why not?” So we took the overnight train together, and sat up and talked most of the night.

Alexis: Oden told Likens that he thought that the pollution in Scandinavia was coming from more industrialized parts of Europe, and this information helped Likens connect some dots.

Lisa : It’s like he had to talk to someone else from across the globe to understand what was happening in his own little corner of the world. And this is a bigger theme in science I think we hear again and again. You have to step outside of your framework to see the big picture.

Alexis : Exactly. No one is ever just working on one thing in isolation by themselves. Lots of people are working on the same thing all over the world and they benefit from talking to each other.

Likens: It was just one of those serendipitous events where something happens and helps you understand what’s going on much more clearly than you might’ve otherwise.

Alexis: Likens went back to the U.S. and continued monitoring acid rain. Then in 1974, eleven years after he first discovered it, he decided he had enough evidence to write an article with his colleague Herbert Bormann for the academic journal Science . It was called “ Acid Rain: A Serious Environmental Problem .” By this point Likens had moved to upstate New York and had also found acid rain in the Adirondacks.

Likens: The paper was saying, “This is not something unique to Hubbard Brook but is a much more regional problem.”

Alexis : The paper said that acid had been falling in the Northeast for 20 years. But the biggest revelation was that tall smokestacks hundreds of miles away in the Midwest were to blame.

Emissions from burning coal was a major source of the problem.

Likens: The Midwest is emitting large quantities of sulfur and nitrogen Oxides. It gets carried to the atmosphere and then deposited here whenever it rains and snows. So it’s like somebody throwing their garbage out and then the garbage falling on your property and you don’t like it much.

Alexis : The idea that pollution could travel such distances was a new revelation. And the irony of it all was that the culprit—those tall smoke stacks—were originally created as a solution to another pollution problem.

Donora, Pennsylvania News Clip: Residents have difficulty breathing the murky air. 20 died. 400 others are stricken with respiratory illness. A local zinc plant is suspected of emitting poison smoke is closed down. An epidemic of pneumonia is feared in the wake of Donora’s deadly rain of smog.

Alexis : Donora was a small mill town in western Pennsylvania. Back in the 1940, their zinc plant, like most plants at the time, had a short smoke stack, and it was pumping out a poisonous combination of carbon monoxide, sulfur dioxide, and metal dust. In 1948 the town suffered a smog attack that killed twenty people and made seven thousand more sick. The disaster alerted people to the hazards of air pollution, and it eventually helped trigger the 1970 Clean Air Act. But it also raised the height of smokestacks.

Lisa : Tall smokestacks helped towns like Donora, they whisked clouds of pollution out of their backyards. But unfortunately they just sent them to other people backyards, further away.

Likens : And what that really did was convert a local soot problem to a more regional soot problem. It just took the push from here and emitted it at a higher level and then it was swept away by the winds and the atmosphere.

Chapter 2: Get Evidence Alexis: Chapter 2: Get evidence.

Lisa : By the time Gene Likens and Herbert Bormann published that paper in 1974, they’d been monitoring the issue for more than a decade.

Alexis : So maybe you’re wondering what they were doing all that time. I mean we certainly were.

Lisa : The answer is gathering that evidence. First they went to some of the most remote places in the world to try to get a baseline estimate of what the acidity, or pH, of rain should be. They had to go places without human activity or any smokestacks—tall or short. Just a few of the places they went were Southern Chile and remote parts of China and Australia. They traveled for a month by boat to get to an island in the middle of the Indian Ocean called Amsterdam Island.

Through it all they learned that the default pH of rain is 5.1. The samples they were measuring back home were at least a hundred times more acidic than that. Here’s how an ABC news clip explained what these numbers meant.

ABC Evening News, December 14, 1978: A pH of 7 would be neutral, the lower the reading the more acidic it is. This sample of rainwater from the summit reads 3.3, which is just about as acidic as grapefruit juice.

Lisa : Likens’s world travels really proved that the rain truly was too acidic. His research also proved that the pollution that caused acid rain really was coming from industry in the rust belt.

Likens : We tried to follow isotopic tracers in the emissions from smokestacks in the Midwest. We followed plumes in small airplanes and vehicles on the ground. We went to enormous lengths to try to answer those questions.

Lisa : Ten years in it seemed like the science was pretty clear. Likens and his team felt confident in their research and they published their article. Some of what they hoped for started to come true. The New York Times quickly picked up their story and the scientific community in the U.S. started paying attention to acid rain.

Likens: That paper changed my life forever because it was published on the front page of the New York Times . I had colleagues all over the world calling me saying, “Likens, what is this? What’s going on?”

Lisa: Environmental scientists definitely took notice. But so did plenty of other people, many with their own agendas.

Likens : There was lots of pushback saying, “Well, it’s not us.” You know, “We didn’t do it. It’s not us. There is no such thing as acid rain.” I can remember many times when there would be a meeting or I might be giving a talk and someone, a denier type would stand up and say, “There’s no such thing as acid rain.” And I would say, “Have you ever collected a sample of rain and analyzed it?” The answer was always no. I said, “Try it sometime. You might be surprised what you find out.”

Rachel Rothschild: There was this pretty dramatic response from the coal industries, who were thought to be the most serious contributors to the problem.

Lisa: Rachel Rothschild is a historian of environmental science and technology and a former research fellow at the Science History Institute. She’s finishing up a book called Poisonous Skies: Acid Rain and the Globalization of Pollution. She’s studied the pushback against acid rain science, and one of the things she’s uncovered is how quickly the coal industry realized that

Likens’s research could be a threat to them.

Rothschild: They, in fact, launched some of the most serious and extensive research efforts on acid rain in the hope of vindicating themselves, and it set up a very interesting confrontation between industry scientists and environmental scientists in the late 1970s and into the 1980s.

Lisa : So we’ve been here in step two, gathering evidence with Gene Likens, thinking we were alone with him.

Alexis : But it turns out these steps—which we made up by the way—aren’t secret! Other people can jump in and gather evidence too!

Lisa: So with acid rain step two is multi-pronged: first you have to gather your evidence, then wait for someone else to dispute or distort it, and meanwhile they’re gathering their evidence, and then you have to dispute the counter-evidence. When the attacks came they were often aimed right at Gene Likens.

Likens: It was bad. It was really nasty. I had a contract put out on me. It was…Did I tell you this story before? If so I apologize. Oh my goodness, I hadn’t thought about any of this in a long time, really painful.

Lisa : A coal-backed policy group tried to carry out what we can only describe as a “scientific hit” on Gene Likens. Okay, maybe that’s a little extreme, but they put out a call to discredit his research on acid rain—they called him by name—and offered to pay four hundred thousand dollars to anyone who could do the job.

Likens : That was the call. Show that he is wrong. So yeah, it was pretty unsettling and pretty shocking. It wasn’t a contract on my life, but it was a contract on my career, which in some ways almost was as important as my life. I mean, not really but you know what I mean? It’s what I do. It’s what I am. It’s what I’m all about. I grew up on a small farm in northern Indiana. I was a farm boy. I just thought the world worked a little differently and I kept finding out it didn’t. I thought all this

science rode around like knights on big white horses and I found out it didn’t work that way. Answers could be purchased and they were. All that was greatly disturbing to me.

Alexis : So I think this is a good place to stop because this is a pattern we’ve seen before, right?

The naiveté of scientists playing by the rules, but they don’t really understand all of them. Or

they see rules that aren’t there. They are just in their lab doing their thing and not really thinking about how to play this larger game.

Lisa : What happens when the research hits the real world? Yeah, the game can change a lot.

Alexis : Exactly.

Lisa : It’s partly that naïve sense of playing by the rules maybe? That might help certain scientists when they get to a crisis point, because in the end they have the science to go back to.

Likens: Why did we keep persevering? [laughs] Because I’m a scientist and because I am searching for the truth and because in science we search for the truth. We rarely find it, but we search for the truth.

Lisa: The contract Likens is talking about was put out by one of the biggest sources of counter- research—a coal trade group called the Edison Electric Institute. Their research arm was called EPRI, or the Electric Power Research Institute. Their job was to refute any science that made them look bad, and they were desperate to find some other industry to blame acid rain on.

Rothschild: They were hoping that they might find that, say, logging or other forestry practices, for example, might result in increased acidity in the soil.

Lisa : So EPRI scientists conducted a study in the Adirondacks to get alternative evidence, alternative facts if you will, but they couldn’t find any. So they distorted the evidence.

Rothschild: I would say they misrepresented the evidence and tried to convey that there was more uncertainty than there actually was and tried to use evidence that simply supported a different kind of proposition, to say that actually acid rain wasn’t the problem at all.

Lisa : That scientific hit never paid off. Remember how Gene Likens spend those eleven years of gathering evidence?

Likens: It all started with measurements and was bolstered by continuing high quality measurements so that when the attacks came we were able to lay our data out there and say, “Go at it and show that it’s wrong,” and nobody was ever able to do that.

Chapter 3: Let the Public Know

Lisa: Chapter three. Let the public know.

Alexis : Gene Likens learned that his data was crucial, but it was not going to speak for itself. So he had to learn how to talk to the public and the naysayers. When he wrote that pivotal paper in 1974 he consciously chose the term “acid rain” because he thought it would get people’s attention, and he was right.

Likens : We thought and argued long and hard about whether we should use that as a title. I’m really glad that we did because it brought public attention to the issue in ways, and I’m a scientist, so I’m not supposed to care about that, but in terms of the management of this serious environmental issue it helped. Because you can walk in the rain, you can sing in the rain, you can dance in the rain, but if the rain is acid you might think about it very differently than you would have otherwise.

Alexis: In the late 70s and early 80s television played a crucial role in getting the American public to know and care about acid rain. Robert Bazell worked at NBC news for 38 years. He was the chief science correspondent during the 1980s.

Robert Bazell : Well the media landscape was that there were three networks and most of America watched one of the three every night. There was no cable television.

Newspapers were not going out of business for all the things we think about now. And of course, there was no Internet. It was a very different world, and there was an enormous amount of impact from those stories that were on television.

CBS Evening News, September 11, 1979: Well, as far as I’m concerned the lake is dead. Period. There’s no swallows around, the swallows have left almost two weeks early this year.

Alexis: This is one of the earliest stories on Acid Rain, from 1980.

NBC Evening News, May 9, 1980: Now there are no fish, no lily pads. In fact, there is no life visible in Woods Lake. It was killed by a new type of pollution which is affecting many parts of the world. It’s called acid rain.

Alexis : 38 years later Bazell still remembers reporting it.

Bazell: We were always looking for stories, and this one was an important one, obviously, for the reasons that you just heard in that clip. Fish were dying, trees were dying. It was a visual story, which makes it very impactful for television. Made it a very easy story to tell. You could see what was happening, it wasn’t an obscure concept.

Alexis : Everyone was talking about acid rain, from TV reporters—like Robert Bazell—to cartoons, to the Pope. That’s right, the Pope. In 1985 Gene Likens visited Pope John Paul II, who went on to address acid rain in his encyclical. So the media helped. But it also might have hurt.

The MacNeil/Lehrer Report, May 26, 1980 [Jim Lehr] : There is a new environmental fear alive in the land, the fear of something called “acid rain.” Reports of its presence and its danger come from everywhere.

Alexis : This is Jim Lehrer, in a 1980 clip from the Macneil/Lehrer Report , the precursor to PBS Newshour . On the show Lehrer holds what is basically a debate. On one side is Douglas Costle, Jimmy Carter’s EPA administrator, and on the other is a man named William Poundstone. He’s the executive vice president of Consolidated Coal—one of the country’s biggest coal companies. Throughout the show Costle lays out well-established facts about acid rain and Poundstone disputes them. Or more accurately, he evades and distorts them.

The MacNeil/Lehrer Report, May 26, 1980 [Charlayne Hunter-Gault] : Mr. Costle, what has brought you to your present state of alarm?

Douglas Costle: I think the single most important thing that happened this year was that scientists from all around the world came to me and they said, in effect, “there`s a lot we still do not know about acid rain, but we know enough now to know that we should not be making the problem worse.”

Lehrer : Mr. Poundstone, what do you think of Mr. Costle`s position on acid rain?

Poundstone : There is no issue that the rainfall is acid. But we go beyond that point, and we start to diverge.

Lehrer : In other words, you will concede that there is such a thing as acid rain?

Poundstone : Yes, sir. The rain—

Lehrer : And it’s a damaging—it has serious repercussions when it hits the ground?

Poundstone : I have not said that. I have said the rain is acid.

Lisa and Alexis: “Ohhhhhhh” do you see what’s going on here? I think we can all see what’s going on here.

Poundstone : And there’s a great deal of argument and evidence that must be heard on this issue. The English Electricity Board, the EPRI people as well—

Lehrer : Who are the EPRI people?

Poundstone : That is the research arm of the Electric Power Research Institute.

Lehrer : I see. All right.

Poundstone : They have some $22 million a year in research activity, and I think in these areas are doing more than anyone.

Alexis: Poundstone’s goal was to discredit acid rain science, and this interview made it seem like there was no scientific consensus at all. If you’ve been paying attention to this podcast you already know this is what EPRI was all about. But Jim Lehrer takes everything both men say at face value, seemingly encouraging his viewers to do the same. Imagine you’re sitting at home watching this on the news, they’re the same to you. But they’re not the same.

Lisa : We see this kind of false equivalence all the time. Especially with environmental issues.

Alexis : Right, so that’s why Douglas Costle spent a lot of time playing defense during the Lehrer interview, but he still managed to squeeze in the fact that there was an attainable solution: older power plants could be retrofitted with a technological fix to reduce their emissions.

Lisa : I’m just speculating here, but it seems like that interview must have caught him off-guard, like it felt like a big setback. Just three weeks after this interview Douglas Costle said this on the ABC evening news:

ABC Evening News, June 18, 1980 [Douglas Costle]: I don’t want to sound too cynical, but I have never seen an industry that is a part of the problem, be the first to acknowledge a problem. Or the extent of their own involvement in it.

Alexis : Despite all of this it seemed like things were moving ahead. President Carter signed the acid precipitation act of 1980, which promised to address the problem within ten years. Things were looking up. And then this happened.

Ronald Regan Election Speech Jan. 20. 1981: In this present crisis, government is not the solution to our problem; government is the problem.

Chapter 4: Implement Policy

Alexis : Chapter four. Implement policy.

Lisa : Or, in the case of acid rain: intentionally waste a decade not implementing any policy!

Alexis: It turns out elections have consequences.

Rothschild: So Reagan had really campaigned, much like President Trump did recently, on this idea of deregulating the environment and making sure that environmental regulations weren’t getting in the way of economic development and growth. When he came into office, he very quickly transformed the Environmental Protection Agency.

Lisa : Douglas Costle didn’t last long in Reagan’s EPA. Instead the president brought on one of EPRI’s top scientists—remember them? Another new EPA pick banned the use of the term acid rain. In short, Reagan was not good for the environment. He did, however, invite a team of scientists to brief him on the issue at the White House in 1983. The group was led by Gene Likens.

Likens : At the end, President Reagan sat back in his chair and he looked around the room and he said, I’ll never forget this quote, “Well, gentleman it’s clear to me that my undergraduate education did not prepare me for such complicated issues.” I thought, “Wow.” But any rate we made our case and that was in September of 1983 and on January the Director of Management and Budget made the pronouncement that, “no, we’re not going to deal with acid rain. It’s too expensive to do so. We’ll study it instead.”

It was an amazing experience to go to the White House and to brief the president and the full cabinet, but not to see something happen.

Lisa : In 1986 Reagan suffered a backlash in the midterm elections, and results sent a message that he needed a different approach to environmental issues. So he signed the Montreal Protocol for the ozone hole, and the Sophia Protocol, an international accord aimed at reducing nitrogen oxides to combat acid rain. The environment became a huge campaign issue in the 1988 election.

Michael Dukakis attack ad: For seven and half years George Bush personally weakened regulations on corporate polluters. And now suddenly George Bush tells you he is going to be the environmentalist president. Do you believe that?

Lisa : On the left was Michael Dukakis, who obviously did not win. But Rachel Rothschild says he made a lasting impact.

Rothschild: So, Dukakis really placed environment at the forefront of his political platform during the election, and in many ways forced President Bush to move to the left on that issue and make a decisive break with President Reagan.

Lisa: Part of the public’s anxiety was a growing awareness of something called global warming.

Rothschild: In the summer of 1988 there were congressional hearings about the possibility that carbon dioxide was increasing the planet’s temperature with the potential for catastrophic results to the environment.

The MacNeil/Lehrer Report, June 30, 1988 Congressional hearing [Daniel Albritton, NOOA] If greenhouse gases continue to grow unabated…

[Rep. Claudine Schneider [R] Rhode Island]: There is a very high, high risk of irreversible, and catastrophic impact looming on the horizon.

Rothschild : And that I think, for the first time for many Americans, raised the specter of large scale planetary threats from fossil fuels. And so acid rain, in comparison, almost seemed much more solvable.

Likens: I often wondered if I was just banging my head against the wall for no value. But that didn’t turn out to be the case, did it? Because in 1990 under amazing conditions a Republican president signed the 1990 Clean Air Act into legislation.

NBC Evening News, Nov 15, 1990: What the President is calling for would be the first improvement of the clean air law in 12 years.

President George H. W. Bush : We’ve seen a stalemate. It’s time to clear the air. Acid rain must be stopped and that’s what we all care about.

President George H. W. Bush, address to Congress February 9, 1989: Because the time for study alone has passed and the time for action is now.

Likens : The Congress, both the House and the Senate had voted overwhelmingly, it wasn’t unanimous, but it was overwhelmingly in favor of that action, the 1990 Clean Air Act Amendments. So being able to be there in 1963 and make the discovery for North American about the occurrence of acid rain, and then all those tough years in between to 1990 when our country took legislative action, was very satisfying, and maybe is unique. I don’t know.

Lisa : Bush implemented what is now known as “cap-and-trade.” It essentially lets companies buy and sell the rights to pollute. It was a perfect free-market solution for a Republican, environmentalist president.

Alexis : You might have noticed that we left out the “get industry on board” step, that’s because, well, they never really got on board, per se, eventually they just had to yield to the change in policy.

Chapter 5: What Does Success Look Like?

Alexis: The cap and trade program was a cost-effective solution, and it stemmed the worst environmental impacts. The rain at Hubbard Brook is 80% less acid now than it was in 1963. But there are still areas of the country that are still at risk or haven’t fully recovered, so it’s a success story, but it’s complicated.

Lisa : The lesson of Gene Likens is the same lesson of Hubbard Brook forest. The mountains of New Hampshire do not exists in a vacuum and neither does Gene Likens and his science.

Alexis: Right. Exactly. And we’ve seen this—

Lisa: Both of them are touched by industry, and social concerns, and money and power and all of that stuff.

Alexis : And by the way, Gene Likens still has not given up the fight.

Likens: No way. And I still don’t. I’m in my mid-eighties and I’m not giving up yet. Here I am talking to you.

Alexis : Distillations is more than a podcast. We’re also a multimedia magazine.

Lisa : You can find our videos, our blog, and our print stories at Distillations DOT org.

Alexis : And you can also follow the Science History Institute on Facebook, Twitter, and Instagram.

Lisa : This episode was produced by Mariel Carr and Rigo Hernandez. Additional sound was recorded by Dave Rainey.

Alexis : This show was mixed by James Morrison and our theme music was composed by Zach Young.

Lisa : For Distillations I’m Lisa Berry Drago.

Alexis : And I’m Alexis Pedrick.

Alexis and Lisa : Thanks for listening!

Listen to more episodes

Exploring ‘Health Equity Tourism’

With a new public interest in health equity research, who is actually receiving recognition and funding in the field?

The Mothers of Gynecology

Why are Black women in America three times more likely to die during childbirth than White ones?

Correcting Race

A group of medical students wants to take racial bias out of the equation.

Never Miss an Episode

Copy the above HTML to republish this content. We have formatted the material to follow our guidelines, which include our credit requirements. Please review our full list of guidelines for more information. By republishing this content, you agree to our republication requirements.

• Environment
• Global Affairs

Acid rain: A case study in Canada-US relations

On March 11, 1981, when Ronald Reagan visited Ottawa for the first time as president of the United States, he was greeted by thousands of protesters on Parliament Hill. They shouted and held placards that conveyed a single powerful message: “Stop Acid Rain!”

Thirty years ago, acid rain was at the top of the Canadian public policy agenda. Canadians were literally shouting at the rain. But it wasn’t even on the American radar screen.

Flash forward to March 13, 1991, 10 years almost exactly to the day from President Reagan’s visit, when the first President Bush and I signed the Acid Rain Accord in the Reading Room of the Centre Block on Parliament Hill.

In 10 years, we went from yelling at one another, to talking to one another, to negotiating with one another, to making an important agreement with one another.

Now, as we celebrate the anniversary of the Accord signed 21 years ago, acid rain is no longer a public policy issue. Not only has the dispute been resolved, the problem has been solved.

And the question is, how was it done?

Well, we simply wouldn’t let go of it. We got in the Americans’ face about it at every bilateral meeting until they realized we were serious about it, that we meant it, and that we wouldn’t go away until we had dealt with it to our satisfaction.

I regarded it as a litmus test of Canada-US relations, and said so to both Presidents Reagan and Bush. In fact, on a visit to Ottawa in January 1987, then Vice-President George H.W. Bush said he “got an earful on acid rain.” He certainly did.

Even then, it took seven years from the time I first raised it with President Reagan in 1984 until the moment we signed the Acid Rain Accord in 1991.

And then at the Shamrock Summit in Quebec City in March 1985, President Reagan agreed to an envoy process on acid rain. He appointed his former transportation secretary, Drew Lewis, as his envoy, and I appointed former Ontario premier Bill Davis as Canada’s. They reported directly to the president and the PM.

With the appointment of such outstanding and influential envoys, for the first time, things started to move. Up to then I thought President Reagan was just being polite in hearing me out. Now he had engaged. When the president engages, the White House engages, and when the White House engages the entire administration engages.

On January 9, 1986, the special envoys released their report recommending as a first step that the US invest $5 billion to create more efficient technology for clean burning energy, especially coal. Then on March 19, 1986, during our Shamrock II Summit in Washington, President Reagan gave his full endorsement to the report of the special envoys.

But while we were talking to the Americans, we were taking action with the provinces and industry, implementing the Clean Hands Policy of leading from the front.

First, in February 1985, even before the Shamrock Summit, we got an agreement with the seven provinces east of Saskatchewan to reduce sulphur dioxide emissions by 50 percent, by 2.3 million tonnes from the base year levels of 1980 by 1994. We did this within only six months of taking office.

Then we told industry they had to clean up their act. For example, the Inco smelter at Sudbury was the biggest producer of SO2 emissions in Canada. When we told them they had to cut emissions by half, they told us they’d go out of business. But we held the line and guess what, they commercialized the sulphur and their profits went up instead!

There were two reasons for adopting the “Clean Hands” approach. First, it was the right thing to do. And second, it provided strong empirical evidence against the argument in Washington that the only reason we wanted an acid rain cleanup was so that Canada could sell the US more clean hydro-electricity.

This was the view held by Senator Robert Byrd, the Senate Majority Leader who was from West Virginia, a coal-producing state.

In April 1987, the New York Times captured his adamant opposition in a timely headline: “Byrd opposes legislation to curb pollution that causes acid rain.” The story reported: “Robert C. Byrd, the Democratic leader, said today that acid rain ‘is not an emergency’ and denounced legislation proposed to control the sources of the pollution that causes it.’“ This is what we were up against on Capitol Hill.

To this day, the coal lobby remains extremely powerful in Washington, one of the reasons progress is so difficult on climate change. For example, the coal-fired energy industry in America produces a carbon imprint more than 50 times the size of the Canadian oil sands. You don’t hear that from celebrity demonstrators in Washington.

Things would improve remarkably when George Mitchell became Senate majority leader in 1989, at the same time the first President Bush took office. This was a happy coincidence. Though he was a Democrat and Bush was a Republican, they had two things in common: they were both committed environmentalists — Bush had said he wanted to be known as “the environmental president” — and both had homes in Maine, one of the states most seriously damaged by acid rain.

But I’m getting ahead of the story.

There are three elements to Canada playing an important role on the environment: first, leading by example, claiming the high ground; second, engaging the Americans at the highest level of government; third, involving industry in solutions.

It is well known that President Reagan and I became very good friends and cooperated closely on major initiatives involving global and bilateral strategy.

The cornerstone of Canada’s remarkable influence in the US has to be its special relationship with the president and the people of the United States of America.

Winston Churchill had foreseen this in a brilliant speech in 1939. He described our relationship and the promise it held this way: “That long frontier from the Atlantic to the Pacific oceans, guarded only by neighbourly respect and honourable obligations, is an example to every country and a pattern for the future of the world.”

This unique relationship so carefully nurtured by some prime ministers and governments was then leveraged exponentially by them vis-à-vis other nations whose support for Canada and its initiatives was affected by the perceived high personal regard in which the prime minister of Canada was clearly held by the president of the United States and the consequent influence we enjoyed throughout the administration and Congress.

This special relationship of two great nations was based on shared fundamental values — liberty and democracy — and we did not hesitate to defend them from attack. There are reminders of that from the trenches of one war to the beaches of the next, places inscribed in the history of valour, where Canadians and Americans have fought together, where Canadians and Americans have died together in the defence of freedom.

No prime minister expressed this better than Lester B. Pearson, whose name graces this building and who wrote in his memoirs: “We should exhibit a sympathetic understanding of the heavy burden of international responsibility borne by the United States, not of her own imperial choosing but caused in part by the unavoidable withdrawal of other states from certain of these responsibilities, or, if you prefer, from imperial power and privilege. Above all, as American difficulties increase, we should resist any temptation to become smug and superior: ‘You are bigger but we are better’. Our own experience, as we wrestle with our own problems, gives us no ground for any such conviction.”

It is amusing to note that, in some Canadian quarters, friendly relations with the president of the US are viewed with scorn and alarm. A relationship that leaders of other nations would treasure is derided by these same critics — supercilious and uninformed as they are — as subordination, unworthy of an independent nation.

Frank Carlucci, President Reagan’s national security adviser and secretary of defense, describes in an oral history project at the University of Virginia how testy President Reagan became when his officials continued to stall and stymie my government on issues ranging from acid rain to Arctic sovereignty to free trade:

According to a recent account by Jeffrey L. Chidester, Research Director for Presidential and Special Projects at the University of Virginia, before entering 24 Sussex during a state visit in 1987, President Reagan took Carlucci aside and said: “I think we should do something for Brian.” Whereupon Carlucci said: “Mr. President, we’re doing well holding our positions on acid rain, the free trade agreement and the Northwest passage.” “Oh, no, no, no,” said Reagan, “we ought to do something.”

Chidester writes, “After lunch, Carlucci continued to push for the American position. ‘I said [to the president] no, no, we’re holding to our positions. These are well established positions.

“It was the only time I saw Ronald Reagan lose his temper. He turned to me and said: ‘you do it.’ Carlucci went right from the meeting and grabbed Derek Burney, Mulroney’s Chief of Staff and asked: ‘Derek would you re-iterate your positions [on acid rain, trade and the northwest passage?]’ When Burney asked why, Carlucci said: ‘Because they’re our positions now.’”

Immediately after that exchange President Reagan sat with his cabinet officials and senior advisers behind closed doors in the living room at 24 Sussex and amended his speech to Parliament slated for that afternoon.

For the first time ever, he wrote that he “agreed to consider” a bilateral agreement with Canada over acid rain and added a promise “to inject new impetus” into talks regarding recognition of Canadian sovereignty over the Arctic.

Professor Chidester concluded: “Personal diplomacy was the only way to break the bureaucratic inertia on these issues.”

Only if you have seen the dramatic manner in which a signal from the president galvanizes an entire administration into action can you fully appreciate the significance of such leadership.

Finally, in 1991, we signed the Acid Rain Accord with the first President Bush. Both President Reagan and President Bush rejected the advice of some of their key officials on acid rain, because of the special relationship between the United States and Canada, and the personal rapport between president and prime minister. They knew it was a festering problem for Canada and resolved it in a manner favourable to us. Anyone who tells you that personal friendship doesn’t count in the conduct of foreign affairs — that nations only have interests and nothing else — doesn’t have a clue what he is talking about.

That is why I am confident in the future of our most important bilateral relationship. Both Prime Minister Stephen Harper and Foreign Minister John Baird have the skill, tenacity and perspicacity to persuade the American leadership to accept the value of many

Canadian positions on important questions of public policy.

The Clean Hands approach also gave us moral leverage when I was given the high honour of addressing a Joint Session of the US Congress in April 1988.

Here’s what I told them: “You are aware of Canada’s grave concerns on acid rain. In Canada, acid rain has already killed nearly 15,000 lakes, another 150,000 are being damaged and a further 150,000 are threatened. Many salmon-bearing rivers in Nova Scotia no longer support the species. Prime agricultural land and important sections of our majestic forests are receiving excessive amounts of acid rain.”

And here’s where the Clean Hands came in, allowing me to put the onus on the Americans to act. “We have concluded agreements with our provinces to reduce acid rain emissions in eastern Canada to half their 1980 levels by 1994. But that is only half the solution — because the other half of our acid rain comes across the border, directly from the United States, falling upon our forests, killing our lakes, soiling our cities.”

I continued: “The one thing acid rain does not do is discriminate…It is damaging your environment from Michigan to Maine and threatens marine life on the eastern seaboard. It is a rapidly escalating ecological tragedy in this country as well.

“We acknowledge responsibility for some of the acid rain that falls on the United States. Our exports of acid rain to the US will have been cut in excess of 50 percent. We ask nothing more than this from you.”

I left the Joint Session of Congress with this question: “What would be said of a generation of North Americans that found a way to explore the stars, but allowed its lakes and forests to languish and die?”

Fortunately we averted such a damaging verdict of history, by forging ahead until we got an agreement.

In addition to raising acid rain at five annual meetings with President Reagan, including the G7 summit in Toronto in 1988, I also scheduled meetings with George Bush when he was vice-president, both in Washington and Ottawa.

I invested heavily in my relationship with George Bush, and we have remained very close friends over 30 years to this day. There were three reasons why I spent so much time with him when he was vice president. First of all, I liked him a lot. He was and remains a highly principled and accomplished man whose presidency added to the lustre of America’s great international achievements. Second, I thought he was going to win the Republican nomination and the presidency in 1988 and I wanted Canada to have a privileged relationship with him.

And third, he cared about the environment and the acid rain file.

And I knew that if we were going to get it done, it would be on his watch as president.

There were two things that stood out about George H.W. Bush. First, he knew his files cold. He didn’t just take his brief, he knew his brief, and he knew the acid rain file better than any of his officials.

And second, by the time he became president in 1989, he had served as vice-president for eight full years, and arrived in his office with a fully formed agenda of what he wanted to do in the White House.

And one of the things he wanted to get done was an acid rain accord with Canada.

After he took office, and just before his first State of the Union Address, he called me and said he wanted to come to Canada on his first foreign visit, and we quickly arranged for a working session at 24 Sussex.

He also told me on that call that he had gone to Camp David with a briefing book that dealt with nothing but acid rain. And when he came down from that mountain, he was clearly determined to press ahead.

And he did, even later during the recession of 1990-91, at a moment when the environment would normally have fallen off the table as a priority in Washington or, for that matter, in Ottawa.

There was a lot of resistance from inside his own administration. His chief of staff, John Sununu, opposed action on acid rain, even though he came from New Hampshire, one of the states most affected by it. The vice president, Dan Quayle, was the chairman of the Competitiveness Council, and he was hearing a lot of opposition from the business community to our proposed actions.

We simply wouldn’t let go of it. We got in the Americans’ face about it at every bilateral meeting until they realized we were serious about it, that we meant it, and that we wouldn’t go away until we had dealt with it to our satisfaction.

President Bush was having none of it. When he came back from that weekend at Camp David, he told his team: “We owe this to Canada. We owe this to the Mulroney government, which has been pressing this issue on us now for five years nonstop. And we owe it to our common environment to do this.”

On his visit to Ottawa on February 10, 1989, standing at the front door of 24 Sussex, President Bush stated his “determination to move forward with setting limits (on acid rain pollutants) with legislation and then moving to a discussion with Canada leading to an accord that I think will be beneficial to both countries.”

It was everything we had been asking for, and he delivered, big time. On June 12, 1989, President Bush proposed amendments to the US Clean Air Act , which would be, in his own words, “a comprehensive program to provide clean air for all Americans.” He proposed to reduce SO2 emissions by 10 million tonnes from 1980 levels.

It took another year before the legislation passed. But in the end, for an issue that had been so contentious, it wasn’t even close. On October 20, 1990, the US Senate passed the amended House bill by a margin of 89-10. On October 26, the House passed it by a margin by 401-25.

Finally on November 15, 1990, President Bush signed into law amendments to the Clean Air Act and established the Acid Rain Program. The Act would cut emissions by nearly 10 million tonnes by 2000.

And then on March 13, 1991, President Bush and I signed the bilateral Air Quality Agreement . This was the Acid Rain Accord, but it was more. As the Parliamentary Research Bureau noted in a 1998 paper: “The significance of the Agreement is much broader than acid rain in that it establishes a framework for dealing with other trans-boundary air pollution problems.”

Thus, it could well serve as a template for a bilateral accord on climate change, as it has on other cross-border air issues.

The bilateral accord built on both the US Clean Air Act of 1990 and the Canadian Acid Rain Program of 1985. The goal of 50 percent reduction of SO2 emissions below 1980 levels in Canada had been set for 1994.

As the Parliamentary Research Report notes: “That goal was met ahead of schedule in 1993.”

As it happens, that was the year I left office.

In the 21 years since the signing of the Acid Rain Treaty, few things have given me more satisfaction. We resolved an issue and solved the problem, in the very best traditions of excellence in relations between Canada and the United States.

Today’s young people are the inheritors of a bountiful land, whose pristine beauty and resources have been preserved and enhanced by our action on acid rain.

Today — many years later — that fact gives me enormous personal satisfaction.

Adapted from a speech delivered at the Lester B. Pearson Building on March 13, 2012, the 21st anniversary of the Acid Rain Accord between Canada and the United States.

You are welcome to republish this Policy Options article online or in print periodicals, under a Creative Commons/No Derivatives licence.

Republish this article

by Policy Options . Originally published on Policy Options April 1, 2012

This <a target="_blank" href="https://policyoptions.irpp.org/magazines/harpers-foreign-policy/acid-rain-a-case-study-in-canada-us-relations/">article</a> first appeared on <a target="_blank" href="https://policyoptions.irpp.org">Policy Options</a> and is republished here under a Creative Commons license.<img id="republication-tracker-tool-source" src="https://policyoptions.irpp.org/?republication-pixel=true&post=812&amp;ga4=G-GR919H3LRJ" style="width:1px;height:1px;">

This work is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License .

Related stories

Nature-based solutions are critical to dealing with climate change

B.C. bill on international credential recognition is a good start but needs improvement

The federal government must tackle water pollution from the oilsands

• Environmental Topics
• Laws & Regulations

Science Inventory

You are here:.

EPA Home » Science Inventory » Science and Policy Interactions: A Case Study with Acid Rain

Science and Policy Interactions: A Case Study with Acid Rain

RINGOLD, P. L. Science and Policy Interactions: A Case Study with Acid Rain. Presented at Oral presentation to a class at the Atkinson Graduate School of Management, Willamette University, Salem, OR, October 14, 2010.

Impact/Purpose:

Management of air pollution has a long history in the United States. A succession of laws, with the first Federal law, passed in 1955, has lead to substantial reductions in emissions and improvements in air quality.

Description:

Management of air pollution has a long history in the United States. A succession of laws, with the first Federal law, passed in 1955, has lead to substantial reductions in emissions and improvements in air quality. These laws were simulated originally by acute local effects on human health and ecosystems, but have increasingly been designed to reduce chronic regional effects as well. While analyses show that benefits substantially exceed control costs, the control costs imposed on industries, governments and individuals are substantial. As a result, there has been and continues to be an intimate connection between science and policy in the management of air pollution. A general model showing an idealized relationship between science and policy will be developed and illustrated by examining acid rain research and management. Attention was first drawn to acid rain in the early 1970’s with calls for research and policy attention. In 1979 and interagency effort, the National Acid Precipitation Assessment Program, was established to coordinate research across federal government necessary to inform policy. The ten year program eventually expended $600 million and provided numerous policy relevant reports. As a result of NAPAP research, the clean Air Act Amendment of 1990 developed a program to control acid rain. In contrast to previous “command and control” approaches to manage pollution, and in contrast with approaches considered during policy deliberation throughout the 1980’s, Congress chose to manage acid rain with an innovative cap and trade approach. As a result emissions have been reduced at costs much lower than con template. Continuing monitoring programs show that the aquatic effects of acid rain have been lessened. Economic analyses show that the benefits are about 40 times greater than the control costs. The cap and trade approach is often discussed in deliberations on other pollutants including green house gases.

Record Details:

Planning links:.

• News & Insights
• Media Coverage

The bittersweet story of how we stopped acid rain

Cary's Gene Likens' discovery of acid rain in 1963, set the collective wheels in motion to raise awareness and isolate the cause of acid rain. Not just in North America, but across the industrialized world.

Photo by NatureLifePhoto

• Acid Rain ,
• Environmental Policy

Acid rain went from being a pollution disaster to an environmental success story. How did scientists manage to prove that acid rain existed, and find a way to stop it?

A group of kids canoeing in Canada’s Killarney Provincial Park are paddling across a serene and unnaturally turquoise lake. It’s a hot sunny day, and a thirsty boy dips an aluminium cooking pot into the water to refill his fellow canoeist’s canteens. In a momentary lapse of concentration, the pot slips from his grasp. As it sinks underwater beyond reach, what’s incredible is that it’s visible all the way down to the lake floor some 50ft (15.2m) below.

It’s the mid-1980s. One of the kid canoeists is me, and there’s an unfortunate explanation for this water clarity. This lake, near the nickel and copper smelters of the town of Sudbury, Ontario, has been radically altered by acid rain. Almost every living thing in the water – like the tiny algae that would normally block light from reaching the depths – has gone, leaving the water here and in lakes across the region a beautiful but eerily lifeless aquamarine.

Fast forward to 2019 and another set of lakes in a remote corner of north-west Ontario. Biologist Cyndy Desjardins is sipping coffee at breakfast following a nocturnal boat trip at the International Institute for Sustainable Development’s Experimental Lakes Area (IISD-ELA). Smiling but sleepy, she spent much of the night working in nearly pitch-dark conditions, surveying for tiny monster-like creatures: freshwater opossum shrimp called Mysis relicta. Desjardins is part of a team attempting to close the loop on an acid rain experiment that began in the 1970s.

Bitter controversy

At its worst, acid rain stripped forests bare in Europe, wiped lakes clear of life in parts of Canada and the US, and harmed human health and crops in China where the problem persists. Looking back today, there is little argument that the cause was sulphur dioxide and nitrogen oxides emitted by fossil fuel combustion by cars and industrial facilities like smelters and coal-burning utilities. When combined with water and oxygen in the atmosphere, these air pollutants chemically transform into sulphuric and nitric acid. Acidic droplets in clouds then fall as rain, snow or hail.

We know this now. But for a long time, acid rain was a puzzle. In 1963, as part of a long-term ecosystem study that is still ongoing today, Gene Likens collected a sample of rain at the Hubbard Brook Experimental Forest in New Hampshire’s White Mountains. That sample was “about a hundred times more acidic than we thought it should be”, says Likens, now emeritus professor in ecology at the Cary Institute of Ecosystem Studies in Millbrook, New York. His discovery back in 1963, on the heels of work dating back to 1872 and even earlier, set the collective wheels in motion to raise awareness and isolate the cause of acid rain. Not just in North America, but across the industrialised world.

Other crucial evidence that led to action on acid rain – on both sides of the Canada-US border – came from experiments at north-west Ontario’s Experimental Lakes Area (ELA). Its soft-water lakes were far enough from sources of pollution that they had escaped the effects of acid rain, acting as a control.

Unlike many lakes, composition of the healthy ecosystem in the ELA was well documented. That enabled scientists like David Schindler, then an ELA senior scientist and now emeritus professor at the University of Alberta, Canada, to add acid experimentally to one lake and see how the ecosystem responded. ELA scientists would protectively suit up like Darth Vader, make a sulphuric acid solution and use the boat propeller to mix the cocktail across one of the lakes.

Over seven years beginning in 1976, they lowered the pH of one lake, number 223, from 6.8 (close to neutral) to 5.0 (slightly acidic). Lab studies had suggested a pH of 5.0 would not harm fish. But in the lake 223 experiment, long before it reached 5.0, it did. By the time the pH reached 5.6, most of the lake trout’s preferred food – tiny organisms that require calcium to form exoskeletons – had died as acidified waters dissolved their protective coats.

“Lake trout stopped reproducing not because they were toxified by the acid, but because they were starving to death,” says Schindler.

Freshwater microbiologist Carol Kelly arrived at ELA in 1978 just as acid rain experiments got underway. She became curious about a particular puzzle the lake acidification experiments had stumbled on. Her colleagues had carefully calculated the quantity of acid needed to drop lake 223’s pH to 5.0 – a simple calculation a high-school student could do. But out in the lake it became clear that their calculations were way out of whack.

“I had given the crew orders to take the lake down to a given pH and then add enough acid to hold it there,” says Schindler. Part way through the season, the crew reported that they were running out of acid. Acidifying the lake took way more than they thought, says Kelly. “The question became, where is it going?” she says.

Kelly and colleagues set to work to find out, and discovered that alkali-producing microbes were capable of buffering some of the acidity, helping the lake chemistry to recover. That acid could be neutralised by bacteria living in every lake was a controversial finding at the time.

“People didn’t believe it,” Kelly says. But she continued to find out just how much acid microbes could neutralise, travelling elsewhere in Canada, the US and Norway to lakes that had been acidified atmospherically, to test this natural recovery ability. The discovery that acid-neutralising bugs exist in the sediment in lots of lakes, not just at the ELA, suggested that lakes could recover if the pollution causing the acid rain were eliminated.

Doubt and denial

Compelling photographs of starving fish from lake 223, combined with efforts by environmental groups like the Canadian Coalition on Acid Rain, helped persuade policymakers – eventually – to legislate more rigorous air quality standards.

But acid rain research at ELA almost didn’t happen at all. Founded to address the issue of excess nutrients contaminating lakes, work that had already drawn far-reaching conclusions by the early 1970s, Canada’s federal government was poised to pull the plug on the research station. At a presentation to federal fisheries officials, Schindler says that despite considerable evidence from the US, one official accused him of inventing the idea of acid rain just to save the ELA.

Scientists began pinpointing culprits and journalists covered the problem through the 1970s and 1980s, but some people working in industry were doing their best to obfuscate, sow doubt and delay action.

“There were lots of deniers of acid rain,” says Likens. At the time, Likens remembers giving public lectures on the topic. On occasion someone would stand up, rudely interrupt him, and say they didn’t believe in acid rain. “I would often respond by saying, ‘Well, have you ever collected a sample of rain and analysed it?’ They would say ‘No’ and I would say, ‘Well try it some time.’”

Like with climate change, says Likens, there were many big, powerful, wealthy people involved with vested interests. From its discovery in 1963 to passage of the Clean Air Act in 1990, legislative action on acid rain took 27 years.

Over that time, many a cross-border argument erupted. “The first international altercation over acid rain was the US accusing Canada of acidifying lakes in the boundary waters,” says Schindler. The squabble was over a small coal-burning power plant in Atikokan, Ontario, that US representatives claimed was sending acid rain south of the border. Schindler attended a meeting in Minneapolis, Minnesota, along with other Canadian scientists and their US counterparts.

“When all the data were on the table, it was clear that the little bit of sulphur from Atikokan was inconsequential to boundary waters,” Schindler says. At the same meeting, scientists examined net international flows of emissions. It became obvious, says Schindler, that the US, particularly the Ohio Valley and industrial areas of Pennsylvania and New England, were producing more than half the acid rain that collected in Canadian lakes.

The blame game continued, and acid rain “was at one time the number one Canada-US bilateral issue”, said Adèle Hurley in a speech reflecting on decades of work with the Canadian Coalition on Acid Rain, which she co-founded in 1981. The coalition was eventually disbanded following amendments to the US Clean Air Act in November 1990, establishment of the Acid Rain Program, and parallel action on the Canadian side.

Lessons from the lakes

A half-century after those early experiments, lake 223 in the ELA is no longer acidic, the acid-eating microbes having done their job. Lake chemistry has returned to its pre-experimental state. Biological recovery, however, has lagged behind. Freshwater opossum shrimp are found in healthy numbers in untouched control lakes. But in 223, they are still missing. So, Desjardins and others are investigating whether reintroductions of the opossum shrimp – 10,000 painstakingly counted at a time – might jumpstart biological recovery of the ecosystem.

Early signs look positive. Remote operated underwater vehicles searching for evidence of these mini-monsters of the deep have spotted just two Mysis shrimp swimming freely in lakes thus far, but it suggests that all that midnight catching and counting in the dark is not in vain – these tiny missing links in the ecosystem eroded by acid rain may be coming back. 

Broader recovery, in lakes across North America, happened because acid rain was tackled at its source.

Compared with 1990 levels, sulphate ions in the atmosphere have dropped considerably, reduced to almost negligible levels at former hotspots. But the problem has not disappeared altogether. Nitrates from sources like agriculturally emitted ammonia released from fertilisers and livestock feed remain a contributor to nitric acid precipitation. And there is concern that acid rain – from both sulphur and nitrogen – is an increasing problem in Asia.

There are no simple solutions to complex environmental problems. But are there parallels between efforts to curb acid rain and strategies for action on climate change? Schindler does see similarities in the procrastination tactics employed by industry. “Seed enough doubt, and pay for enough political campaigns, and you can delay action,” he says. “That sounds pretty crass but if you look closely, that’s how most environmental problems are addressed, and climate is no exception.”

Despite this, emissions reductions have been a huge success story in tackling acid rain, says Likens. But further reductions, especially on nitrogen oxides, are needed. The current US president is proposing to cut back regulations on emissions. If this happens, says Likens, recovering lakes in places like the Adirondack Mountains in north eastern New York would be particularly vulnerable, their acid-neutralising capacity already weakened.

Tackling acid rain in North America required actions in two neighbouring countries. But for climate change, the challenge is broader and solutions must be global. Nevertheless, the two issues do share similarities. Both, says Hurley, require cutting-edge science, media coverage and finding common ground, building coalitions between opposing parties.

In the fight Hurley helped to lead against acid rain, this meant talking to coal workers at sportsmen’s shows, engaging them in conversations about clean water for fishing salmon, and going for walks in war cemeteries where acidity was ruining the limestone of gravestones.

Though aspects of its legacy remain, solutions to the acid rain problem moved forward, in North America at least, because it became a non-partisan issue. Hurley reflects that “a broad spectrum of people came to believe that it was important to protect natural resources – our forests, our northern lakes and the fish they contain – resources that belong to everyone”.

If anything can be learned from the acid rain story, it’s that the same breadth of support and dismantling of partisanship is necessary for protecting the Earth’s climate.

More on this topic

Court-defined wetlands

What is a species?

Green Living Seminar - Forest Carbon Offsets: Too Good to Be True?

Stay on top of cary science & events.

Advertisement

Influence of acid rain on slope instability mechanism—a case study in Sichuan provincial highway, China

• Original Paper
• Published: 05 March 2021
• Volume 80 , pages 3659–3673, ( 2021 )

Cite this article

• Dian Xiao 1 ,
• Xiaoyan Zhao   ORCID: orcid.org/0000-0002-7656-7594 1 ,
• Kunpeng Li 1 ,
• Xiucheng Zhao 1 ,
• Hongwei Liu 1 ,
• Xun Li 1 &
• Gai Luo 2  

750 Accesses

8 Citations

Explore all metrics

Acid rain has important influences on the physical and mechanical properties of rock as a result of mineral conversion and dissolution of cement. There are clear spatial correlations between the occurrence of slope failure and rainfall pH value in acid-rain areas. Although some fatal landslides have been ascribed to acid rain, those landslides all consisted of sedimentary rocks that generally contained carbonate minerals, which are particularly susceptible to dissolution in acidic conditions. This paper describes the mechanical deterioration of the structural plane based on acid-rain simulation experiments on a slope cut in hard rock along Sichuan provincial highway S211, China. In the experiments, the cohesion and internal friction angle of the structural plane fell to 35.4% and 6.8% of their original values, respectively, and the strength deterioration exhibited a power-law relationship with the exposed area of the rock bridges. Mineralogical and hydrochemical analyses including polarising microscopy, X-ray diffraction, scanning electron microscopy, and inductively coupled plasma optical emission spectrometry were employed to describe the micromechanisms of weakening. Mechanical weakening of the structural plane is attributed to deterioration of both the composition and the structure. Transformation from hard essential minerals to clay minerals through pyroxene chloritisation, plagioclase illitisation, illite smectitisation, and chlorite dissolution reduced the strength properties of rock bridges. In addition, abundant secondary micro-cracks were formed by propagation of worm-like dissolution pits, thus disintegrating rock bridges and further reducing the strength of the structural plane. This paper provides a better understanding of slope failure mechanisms in areas affected by acid rain.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price includes VAT (Russian Federation)

Instant access to the full article PDF.

Rent this article via DeepDyve

Institutional subscriptions

Similar content being viewed by others

The influence of acid corrosion on dynamic properties and microscopic mechanism of marble

Experimental Study on Deformation and Failure Characteristics of Interbedded Anti-inclined Rock Slopes Induced by Rainfall

New insights into the catastrophic slope failures at Sau Mau Ping: the role of antecedent rainfall pattern

Abedi Koupai J, Fatahizadeh M, Mosaddeghi MR (2020) Effect of pore water pH on mechanical properties of clay soil. Bull Eng Geol Environ 79(3):1461–1469. https://doi.org/10.1007/s10064-019-01611-1

Article   Google Scholar  

Agan C (2016) A preliminary study on the conservation and polishing performance of Sanliurfa limestones as a traditional building material. Bull Eng Geol Environ 75(1):13–25. https://doi.org/10.1007/s10064-015-0729-6

China Meteorological Administration (CMA) (2016) Annual report of acid rain monitoring in China. China Meteorological Administration, Beijing

Google Scholar  

Einstein HH, Veneziano D, Baecher GB et al (1983) The effect of discontinuity persistence on rock slope stability. Int J Rock Mech Min Sci Geomech Abstr 20(5):227–236. https://doi.org/10.1016/0148-9062(83)90003-7

Eppes M, Keanini R (2017) Mechanical weathering and rock erosion by climate-dependent subcritical cracking. Rev Geophys 55(2):470–508. https://doi.org/10.1002/2017RG000557

Fang Q, Hong H, Algeo TJ et al (2019) Microtopography-mediated hydrologic environment controls elemental migration and mineral weathering in subalpine surface soils of subtropical monsoonal China. Geoderma 344:82–98. https://doi.org/10.1016/j.geoderma.2019.03.008

Fereidooni D, Ghobadi MH (2015) Effect of mineralogy on durability and strength of hornfelsic rocks under acidic rainfall in urban areas. J Eng Geol 9(2):2765–2788. https://doi.org/10.18869/acadpub.jeg.9.2.2765

GB/T 50266-2013 (2013) Standard for test methods of engineering rock mass. National standards of People’s Republic of China. China Planning Press, Beijing

Ghobadi MH, Abdilor Y, Babazadeh R (2014) Stabilization of clay soils using lime and effect of pH variations on shear strength parameters. Bull Eng Geol Environ 73(2):611–619. https://doi.org/10.1007/s10064-013-0563-7

Ghobadi MH, Momeni AA (2011) Assessment of granitic rocks degradability susceptive to acid solutions in urban area. Environ Earth Sci 64(3):753–760. https://doi.org/10.1007/s12665-010-0895-6

Ghobadi MH, Mousavi S (2014) The effect of pH and salty solutions on durability of sandstones of the Aghajari Formation in Khouzestan province, southwest of Iran. Arab J Geosci 7(2):641–653. https://doi.org/10.1007/s12517-012-0741-0

Goldich SS (1938) A study in rock-weathering. J Geol 46(1):17–58. https://doi.org/10.1086/624619

Golubev SV, Pokrovsky OS, Schott J (2005) Experimental determination of the effect of dissolved CO 2 on the dissolution kinetics of Mg and Ca silicates at 25 °C. Chem Geol 217(3-4):227–238. https://doi.org/10.1016/j.chemgeo.2004.12.011

Grünthal G (eds) (1998) European macroseismic scale 1998. European Seismological Commission, European Center for Geodynamics and Seismology, Luxembourg, vol 15, pp 99

Gu X, Rempe DM, Dietrich WE et al (2020) Chemical reactions, porosity, and microfracturing in shale during weathering: the effect of erosion rate. Geochim Cosmochim Acta 269:63–100. https://doi.org/10.1016/j.gca.2019.09.044

Gupta V, Ahmed I (2007) The effect of pH of water and mineralogical properties on the slake durability (degradability) of different rocks from the Lesser Himalaya, India. Eng Geol 95(3-4):79–87. https://doi.org/10.1016/j.enggeo.2007.09.004

Hillier S (2000) Accurate quantitative analysis of clay and other minerals in sandstones by XRD: comparison of a Rietveld and a reference intensity ratio (RIR) method and the importance of sample preparation. Clay Miner 35(1):291–302. https://doi.org/10.1180/000985500546666

Kerr PF (1959) Optical mineralogy. McGraw-Hill Book Company, New York, p 442

Knauss KG, Nguyen SN, Weed HC (1993) Diopside dissolution kinetics as a function of pH, CO 2 , temperature, and time. Geochim Cosmochim Acta 57(2):285–294. https://doi.org/10.1016/0016-7037(93)90431-U

Krawczyk-Bärsch E, Arnold T, Reuther H et al (2004) Formation of secondary Fe-oxyhydroxide phases during the dissolution of chlorite–effects on uranium sorption. Appl Geochem 19(9):1403–1412. https://doi.org/10.1016/j.apgeochem.2004.01.017

Land M, Öhlander B, Luleå TU et al (2000) Chemical weathering rates, erosion rates and mobility of major and trace elements in a boreal granitic till. Aquat Geochem 6(4):435–460. https://doi.org/10.1023/A:1009644317427

Li N, Zhu Y, Su B et al (2003) A chemical damage model of sandstone in acid solution. Int J Rock Mech Min Sci 40(2):243–249. https://doi.org/10.1016/S1365-1609(02)00132-6

Li Y, Zhang M, Shu M et al (2016) Chemical characteristics of rainwater in Sichuan basin, a case study of Ya’an. Environ Sci Pollut R 23(13):13088–13099. https://doi.org/10.1007/s11356-016-6363-4

Liu JG, Mason PJ, Yu E et al (2012) GIS modelling of earthquake damage zones using satellite remote sensing and DEM data. Geomorphology 139-140:518–535. https://doi.org/10.1016/j.geomorph.2011.12.002

Liu X, Fu Z, Zhang B et al (2018) Effects of sulfuric, nitric, and mixed acid rain on Chinese fir sapling growth in Southern China. Ecotoxicol Environ Saf 160:154–161. https://doi.org/10.1016/j.ecoenv.2018.04.071

Livingston RA (2016) Acid rain attack on outdoor sculpture in perspective. Atmos Environ 146:332–345. https://doi.org/10.1016/j.atmosenv.2016.08.029

McAdam AC, Zolotov MY, Sharp TG et al (2008) Preferential low-pH dissolution of pyroxene in plagioclase–pyroxene mixtures: implications for martian surface materials. Icarus 196(1):90–96. https://doi.org/10.1016/j.icarus.2008.01.008

Meenakshi, Shrivastava JP, Chandra R (2019) Pedogenically degenerated illite and chlorite lattices aid to palaeoclimatic reconstruction for chronologically constrained (8–130 ka) loess-palaeosols of Dilpur Formation, Kashmir, India. Geosci Front 11(4):1353–1367. https://doi.org/10.1016/j.gsf.2019.11.007

Miao S, Wang H, Cai M et al (2018) Damage constitutive model and variables of cracked rock in a hydro-chemical environment. Arab J Geosci 11(2):19. https://doi.org/10.1007/s12517-017-3373-6

Nespolo M (2021) Pyroxenes. In: Alderton D, Elias S (eds) Encyclopedia of geology, 2nd edn. Academic Press, Salt Lake City, pp 287–296

Chapter   Google Scholar  

Omotoso O (2004) High surface areas caused by smectitic interstratification of kaolinite and illite in Athabasca oil sands. Appl Clay Sci 25(1-2):37–47. https://doi.org/10.1016/j.clay.2003.08.002

People’s Government of Shimian (PGS) (2018) Climatic conditions. http://www.shimian.gov.cn/htm/about.htm?id=79E11D75-75AD-41E8-A672-C14B6F115B18 . Accessed 24 Dec 2019

Rodhe H, Dentener F, Schulz M (2002) The global distribution of acidifying wet deposition. Environ Sci Technol 36(20):4382–4388. https://doi.org/10.1021/es020057g

Schaef HT, McGrail BP (2009) Dissolution of Columbia River Basalt under mildly acidic conditions as a function of temperature: experimental results relevant to the geological sequestration of carbon dioxide. Appl Geochem 24(5):980–987. https://doi.org/10.1016/j.apgeochem.2009.02.025

Shushakova V, Fuller ER, Siegesmund S (2013) Microcracking in calcite and dolomite marble: microstructural influences and effects on properties. Environ Earth Sci 69(4):1263–1279. https://doi.org/10.1007/s12665-012-1995-2

Stoddard JL, Jeffries DS, Lükewille A et al (1999) Regional trends in aquatic recovery from acidification in North America and Europe. Nature 401:575–578. https://doi.org/10.1038/44114

Su X, Tang H, Huang L et al (2020) The role of pH in red-stratum mudstone disintegration in the Three Gorges reservoir area, China, and the associated micromechanisms. Eng Geol 279:105873. https://doi.org/10.1016/j.enggeo.2020.105873

SY/T 5163-2018 (2018) Analysis method for clay minerals and ordinary non-clay minerals in sedimentary rocks by the X-ray diffraction. People’s Republic of China Oil and Gas Industry Standards. China Petroleum Industry Press, Beijing

Taghipour M, Nikudel MR, Farhadian MB (2016) Engineering properties and durability of limestones used in Persepolis complex, Iran, against acid solutions. Bull Eng Geol Environ 75(3):967–978. https://doi.org/10.1007/s10064-015-0821-y

Van Hees PAW, Lundström US, Mörth CM (2002) Dissolution of microcline and labradorite in a forest O horizon extract: the effect of naturally occurring organic acids. Chem Geol 189(3-4):199–211. https://doi.org/10.1016/S0009-2541(02)00141-9

Wahid AS, Gajo A, Di Maggio R (2011) Chemo-mechanical effects in kaolinite. Part 1: prepared samples. Géotechnique 61(6):439–447. https://doi.org/10.1680/geot.8.P.067

West A, Galy A, Bickle M (2005) Tectonic and climatic controls on silicate weathering. Earth Planet Sci Lett 235(1-2):211–228. https://doi.org/10.1016/j.epsl.2005.03.020

Wilson MJ (2004) Weathering of the primary rock-forming minerals: processes, products and rates. Clay Miner 39(3):233–266. https://doi.org/10.1180/0009855043930133

Xiao D, Zhao X, Liao QA et al (2019) Early Palaeozoic arc-related gabbro-diorite suite in East Junggar, southern Central Asian Orogenic Belt: petrogenesis and tectonic implications. Int Geol Rev 62(9):1205–1223. https://doi.org/10.1080/00206814.2019.1641852

Xin P, Liu Z, Wu S et al (2018) Rotational–translational landslides in the neogene basins at the northeast margin of the Tibetan Plateau. Eng Geol 244:107–115. https://doi.org/10.1016/j.enggeo.2018.07.024

Yoon WS, Jeong UJ, Kim JH (2002) Kinematic analysis for sliding failure of multi-faced rock slopes. Eng Geol 67(1):51–61. https://doi.org/10.1016/S0013-7952(02)00144-8

Zhang M, McSaveney MJ (2018) Is air pollution causing landslides in China? Earth Planet Sci Lett 481:284–289. https://doi.org/10.1016/j.epsl.2017.10.045

Zhang YJ, Li Q, Zhang F et al (2017a) Estimates of economic loss of materials caused by acid deposition in China. Sustainability-Basel 9(4):488. https://doi.org/10.3390/su9040488

Zhang YZ, Replumaz A, Leloup PH et al (2017b) Cooling history of the Gongga batholith: implications for the Xianshuihe Fault and Miocene kinematics of SE Tibet. Earth Planet Sci Lett 465:1–15. https://doi.org/10.1016/j.epsl.2017.02.025

Zhao J, Lu C, Deng L et al (2018) Impacts of simulated acid solution on the disintegration and cation release of purple rock (mudstone) in Southwest China. Geomorphology 316:35–43. https://doi.org/10.1016/j.geomorph.2018.05.009

Zhao Y, Cui P, Hu L et al (2011) Multi-scale chemo-mechanical analysis of the slip surface of landslides in the Three Gorges, China. Sci China Technol Sci 54(7):1757–1765. https://doi.org/10.1007/s11431-011-4370-8

Download references

Acknowledgements

The authors would like to appreciate anonymous reviewers for their constructive comments. The authors thank Jiaqi Guo, Qian Fang, and Zhiwei Chen for their laboratory assistance as well as Lucy Muir from Edanz Group and Yong Xiao for language assistance.

This study was jointly supported by the National Natural Science Foundation of China (Grant No. 41672295), Science and Technology Project of Department of Transportation of Sichuan Province (Grant No. 2015B1-1), Major Systematic Project of Scientific and Technological Research and Development Plan of China Railway Corporation (Grant No. P2018G047), and China Geological Survey Projects (Grant No. DD20160345-01).

Author information

Authors and affiliations.

Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu, 611756, People’s Republic of China

Dian Xiao, Xiaoyan Zhao, Kunpeng Li, Xiucheng Zhao, Hongwei Liu & Xun Li

Evaluation and Utilization of Strategic Rare Metals and Rare Earth Resource Key Laboratory of Sichuan Province, Sichuan Geological Survey, Chengdu, 610081, People’s Republic of China

You can also search for this author in PubMed   Google Scholar

Corresponding author

Correspondence to Xiaoyan Zhao .

Rights and permissions

Reprints and permissions

About this article

Xiao, D., Zhao, X., Li, K. et al. Influence of acid rain on slope instability mechanism—a case study in Sichuan provincial highway, China. Bull Eng Geol Environ 80 , 3659–3673 (2021). https://doi.org/10.1007/s10064-021-02170-0

Download citation

Received : 13 September 2020

Accepted : 28 February 2021

Published : 05 March 2021

Issue Date : May 2021

DOI : https://doi.org/10.1007/s10064-021-02170-0

Share this article

Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

• Acid deposition
• Weakening mechanism
• Shear strength
• Mineral conversion
• Micro-cracks
• Structural plane
• Find a journal
• Publish with us
• Track your research

• school Campus Bookshelves
• menu_book Bookshelves
• perm_media Learning Objects
• login Login
• how_to_reg Request Instructor Account
• hub Instructor Commons

Margin Size

• Download Page (PDF)
• Download Full Book (PDF)
• Periodic Table
• Physics Constants
• Scientific Calculator
• Reference & Cite
• Tools expand_more
• Readability

selected template will load here

This action is not available.

4.8: The Chemistry of Acid Rain

• Last updated
• Save as PDF
• Page ID 349389

Learning Objectives

• To understand the chemistry of acid rain.

Acid–base reactions can have a strong environmental impact. For example, a dramatic increase in the acidity of rain and snow over the past 150 years is dissolving marble and limestone surfaces, accelerating the corrosion of metal objects, and decreasing the pH of natural waters. This environmental problem is called acid rain Precipitation that is dramatically more acidic because of human activities. and has significant consequences for all living organisms. To understand acid rain requires an understanding of acid–base reactions in aqueous solution.

The term acid rain is actually somewhat misleading because even pure rainwater collected in areas remote from civilization is slightly acidic (pH ≈ 5.6) due to dissolved carbon dioxide, which reacts with water to give carbonic acid, a weak acid:

\( C{O_2}\left( g \right) + {H_2}O\left( l \right){\text{ }} \rightleftharpoons {\text{ }}{H_2}C{O_3}\left( {aq} \right){\text{ }} \rightleftharpoons {\text{ }}{H^ + }\left( {aq} \right) + HC{O_3}^ - \left( {aq} \right) \tag{8.8.1} \)

The English chemist Robert Angus Smith is generally credited with coining the phrase acid rain in 1872 to describe the increased acidity of the rain in British industrial centers (such as Manchester), which was apparently caused by the unbridled excesses of the early Industrial Revolution, although the connection was not yet understood. At that time, there was no good way to measure hydrogen ion concentrations, so it is difficult to know the actual pH of the rain observed by Smith. Typical pH values for rain in the continental United States now range from 4 to 4.5, with values as low as 2.0 reported for areas such as Los Angeles. Recall from Figure 4.8.1 that rain with a pH of 2 is comparable in acidity to lemon juice, and even “normal” rain is now as acidic as tomato juice or black coffee.

What is the source of the increased acidity in rain and snow? Chemical analysis shows the presence of large quantities of sulfate (SO 4 2− ) and nitrate (NO 3 − ) ions, and a wide variety of evidence indicates that a significant fraction of these species come from nitrogen and sulfur oxides produced during the combustion of fossil fuels. At the high temperatures found in both internal combustion engines and lightning discharges, molecular nitrogen and molecular oxygen react to give nitric oxide:

\[ {N_2}\left( g \right) + {O_2}\left( g \right){\text{ }} \to {\text{ }}2NO\left( g \right)\ \]

Nitric oxide then reacts rapidly with excess oxygen to give nitrogen dioxide, the compound responsible for the brown color of smog:

\[ 2NO\left( g \right) + {O_2}\left( g \right){\text{ }} \to {\text{ }}2N{O_2}\left( g \right) \]

When nitrogen dioxide dissolves in water, it forms a 1:1 mixture of nitrous acid and nitric acid:

\[ 2N{O_2}\left( g \right) + {H_2}O\left( l \right){\text{ }} \to {\text{ }}HN{O_2}\left( {aq} \right) + HN{O_3}\left( {aq} \right)\]

Because molecular oxygen eventually oxidizes nitrous acid to nitric acid, the overall reaction is

\[ 2{N_2}\left( g \right) + 5{O_2}\left( g \right) + 2{H_2}O\left( l \right){\rm{ }} \to 4HN{O_3}(aq) \]

Large amounts of sulfur dioxide have always been released into the atmosphere by natural sources, such as volcanoes, forest fires, and the microbial decay of organic materials, but for most of Earth’s recorded history the natural cycling of sulfur from the atmosphere into oceans and rocks kept the acidity of rain and snow in check. Unfortunately, the burning of fossil fuels seems to have tipped the balance. Many coals contain as much as 5%–6% pyrite (FeS 2 ) by mass, and fuel oils typically contain at least 0.5% sulfur by mass. Since the mid-19th century, these fuels have been burned on a huge scale to supply the energy needs of our modern industrial society, releasing tens of millions of tons of additional SO 2 into the atmosphere annually. In addition, roasting sulfide ores to obtain metals such as zinc and copper produces large amounts of SO 2 via reactions such as

\[ 2ZnS\left( s \right) + 3{O_2}\left( g \right){\rm{ }} \to 2ZnO\left( s \right) + 2S{O_2}\left( g \right) \]

Regardless of the source, the SO 2 dissolves in rainwater to give sulfurous acid ( Equation 8.8.7 ), which is eventually oxidized by oxygen to sulfuric acid ( Equation 8.8.8 ):

\[S{O_2}\left( g \right) + {H_2}O\left( l \right){\rm{ }} \to {H_2}S{O_3}(aq) \]

\[2{H_2}S{O_3}(aq) + {O_2}\left( g \right){\rm{ }} \to 2{H_2}S{O_4}(aq) \]​

Concerns about the harmful effects of acid rain have led to strong pressure on industry to minimize the release of SO 2 and NO. For example, coal-burning power plants now use SO 2 “scrubbers,” which trap SO 2 by its reaction with lime (CaO) to produce calcium sulfite dihydrate (CaSO 3 ·2H 2 O; Figure \(\PageIndex{1}\) ).

Figure \(\PageIndex{1}\) Schematic Diagram of a Wet Scrubber System

In coal-burning power plants, SO 2 can be removed (“scrubbed”) from exhaust gases by its reaction with a lime (CaO) and water spray to produce calcium sulfite dihydrate (CaSO 3 ·2H 2 O). Removing SO 2 from the gases prevents its conversion to SO 3 and subsequent reaction with rainwater (acid rain). Scrubbing systems are now commonly used to minimize the environmental effects of large-scale fossil fuel combustion.

The damage that acid rain does to limestone and marble buildings and sculptures is due to a classic acid–base reaction. Marble and limestone both consist of calcium carbonate (CaCO 3 ), a salt derived from the weak acid H 2 CO 3 . As we saw in Section 4.7 the reaction of a strong acid with a salt of a weak acid goes to completion. Thus we can write the reaction of limestone or marble with dilute sulfuric acid as follows:

\[CaC{O_3}\left( s \right) + {H_2}S{O_4}(aq){\rm{ }} \to CaS{O_4}\left( s \right) + {H_2}O\left( l \right) + C{O_2}\left( g \right) \]

Because CaSO 4 is sparingly soluble in water, the net result of this reaction is to dissolve the marble or limestone. The Lincoln Memorial in Washington, DC, which was built in 1922, already shows significant damage from acid rain, and many older objects are exhibiting even greater damage ( Figure \(\PageIndex{2}\) ). Metal objects can also suffer damage from acid rain through oxidation–reduction reactions, which are discussed in Section 8.9 .

Figure \(\PageIndex{2}\) Acid Rain Damage to a Statue of George Washington

Both marble and limestone consist of CaCO 3 , which reacts with acid rain in an acid–base reaction to produce CaSO 4 . Because CaSO 4 is somewhat soluble in water, significant damage to the structure can result.

The biological effects of acid rain are more complex. As indicated in Figure \(\PageIndex{2}\), biological fluids, such as blood, have a pH of 7–8. Organisms such as fish can maintain their internal pH in water that has a pH in the range of 6.5–8.5. If the external pH is too low, however, many aquatic organisms can no longer maintain their internal pH, so they die. A pH of 4 or lower is fatal for virtually all fish, most invertebrate animals, and many microorganisms. As a result of acid rain, the pH of some lakes in Europe and the United States has dropped below 4. Recent surveys suggest that up to 6% of the lakes in the Adirondack Mountains of upstate New York and 4% of the lakes in Sweden and Norway are essentially dead and contain no fish. Neither location contains large concentrations of industry, but New York lies downwind of the industrial Midwest, and Scandinavia is downwind of the most industrialized regions of western Europe. Both regions appear to have borne the brunt of the pollution produced by their upwind neighbors. One possible way to counter the effects of acid rain in isolated lakes is by adding large quantities of finely ground limestone, which neutralizes the acid via reaction.

A second major way in which acid rain can cause biological damage is less direct. Trees and many other plants are sensitive to the presence of aluminum and other metals in groundwater. Under normal circumstances, aluminum hydroxide [Al(OH) 3 ], which is present in some soils, is insoluble. At lower pH values, however, Al(OH) 3 dissolves via the following reaction:

\[Al{\left( {OH} \right)_3}\left( s \right) + 3{H^ + }(aq){\rm{ }} \to A{l^3}^ + (aq) + 3{H_2}O\left( l \right) \]

The result is increased levels of Al 3 + ions in groundwater. Because the Al 3 + ion is toxic to plants, high concentrations can affect plant growth. Acid rain can also weaken the leaves and roots of plants so much that the plants are unable to withstand other stresses. The combination of the two effects can cause significant damage to established forests, such as the Black Forest in Germany and the forests of the northeastern United States and Canada and other countries (Figure \(\PageIndex{3}\) ).

Figure \(\PageIndex{3}\) Acid Rain Damage to a Forest in the Czech Republic

Trees and many other plants are sensitive to aluminum and other metals in groundwater. Acid rain increases the concentration of Al 3 + in groundwater, thereby adversely affecting plant growth. Large sections of established forests have been severely damaged.

• Harvard Business School →
• Faculty & Research →
• February 1992 (Revised April 1993)
• HBS Case Collection

Acid Rain: The Southern Co. (A)

• Format: Print
• | Language: English

About The Author

Forest L. Reinhardt

Related work.

• September 1992 (Revised October 1992)
• Faculty Research

Acid Rain: The Southern Co. (B)

• September 1993 (Revised October 1993)

Acid Rain: The Southern Company (A) and (B) TN

• Acid Rain: The Southern Co. (B)  By: Forest L. Reinhardt
• Acid Rain: The Southern Company (A) and (B) TN  By: Forest L. Reinhardt

Opinion Can the world really engineer its way out of climate change?

Readers are skeptical. They’re also eyeing their recycling bins with dismay, dreaming of gardens full of native plants and cheering on the EPA.

It was reckless of the Editorial Board to describe large-scale manipulation of the Earth’s climate systems as “cheap and potentially game-changing.” Moreover, the sort of diplomacy the editorial called for is occurring; it just isn’t producing the results The Post prefers.

The Editorial Board criticized the failure to adopt a Swiss proposal at a recent United Nations Environment Assembly. However, the board failed to note that at the same meeting, 54 African countries, with the support of Colombia and other Global South countries, called for a mechanism to ensure that solar geoengineering would not be used. Their objections include concerns that the continent could be used as an experimental zone whose people and lands are harmed first and worst, and worries that such mitigation efforts are just an excuse for wealthy countries to continue consuming in the same damaging ways, and at the same rate.

This echoes the call by more than 450 scholars for an International Non-Use Agreement on Solar Geoengineering , which notes the unacceptable risk posed by solar geoengineering and the impossibility of fair and effective governance in our current world order. These unproven technologies carry incredibly dangerous risks, among them altering weather patterns across the globe with unknown impacts to ecosystems and biodiversity. Agricultural patterns could be upended, threatening food and water supplies for many millions.

Geoengineering is the ultimate dangerous distraction from bringing about what is unambiguously necessary: a just and equitable fossil fuel phaseout. Our governments don’t need to regulate solar geoengineering. For the sake of a truly sustainable future, they need to permanently ban it.

Benjamin Day , Boston

The writer is a senior campaigner with Friends of the Earth’s climate and energy justice team.

I found the April 28 editorial, “ Who gets to decide to re-engineer the weather? ,” somewhat troubling. Sending sulfur up into the air could increase the possibility of acid rain and harm to plants that remove carbon dioxide and feed people. But we do need creative solutions for managing extreme weather.

Some years ago, I sent an idea to NASA about releasing a test dose of biodegradable iron particles into the atmosphere. These would concentrate near Earth’s magnetic poles to protect the ice caps yet allow solar rays to help crops and forests to grow in temperate and tropical zones along the equator. I never heard back, which reflects domestic inertia, not only the lack of international effort mentioned in the editorial. We need an open forum of ideas, supported by carbon taxes, as it seems today’s world is headed toward the disastrous solution of nuclear winter.

Henry Chang , Bethesda

One word: Plastics

Regarding Eve O. Schaub’s April 23 Tuesday Opinion essay, “ How to celebrate Earth Day? Just dump this toxic stuff. ”:

What a disheartening piece on the futility of plastic recycling. I’m not saying it’s incorrect, just sad.

This is not the first time I’ve heard that recycling plastic might be ineffective. Opinions seem to range from the argument that recycling plastic is well-intentioned but useless, to suggestions that the process is pure hype for marketing purposes (so-called greenwashing). Yet my recycle bin overfloweth!

Given this situation, reducing plastic use is critical, and I suggest a good target is packaging. The amount of entirely unnecessary plastic bags, wraps, ties and fillers that come with every consumer item is staggering. In my experience, Apple is a huge abuser in this regard, with even a simple USB cable packed as though it’s a Christmas gift going to the moon. Another example everyone encounters is bedding that comes in sturdy plastic zipper cases. They might look cute lined up on store shelves, but the case could easily be replaced with cloth or cardboard. Take your own inventory; across every type of product and use, excessive plastic packaging is a scourge on the environment and our health.

Of course, a major change would affect the plastics and packaging industries, the workers they employ and the whole supply chain. Somehow we must take that into account as we move toward environmentally friendly solutions.

Eric Wenocur , Olney

Eve O. Schaub’s argument that recycling plastic is a waste of time took a zero-sum approach to an issue that is complicated — and continually improving.

“Plastics” is a broad category of materials with differing chemical compositions and mechanical properties, all of which affect potential recyclability. That is why the recycling rates for different plastic resin types vary significantly, and why the average recycling rate for plastics is low despite some categories of plastics having high recycling rates.

Over the past several years, the recycled-materials industry has made significant investments in technology, education and partnerships to improve plastics recycling rates, and we are seeing improvements as a result for certain resins.

According to the U.S. Plastic Recycling Study , in 2022, more than 5 billion pounds of post-consumer plastic were recovered for recycling (though that figure does represent a slight decline in volume from the previous two years). More than 95 percent of recovered bottles stayed in North America to be remanufactured into new products.

There is still a long way to go, but manufacturers are increasing the use of recycled content and making products that are easier to recycle. They are recognizing the societal value and the demand from their customer base. My organization, for example, is working closely with Colgate-Palmolive, Starbucks and others to address product recyclability and find ways to strengthen recycling across all material categories.

Making a real difference will require a broad commitment from consumers, manufacturers, scientists, engineers and policymakers. This effort is worth everyone’s time.

Robin Wiener , Washington

The writer is president of the Recycled Materials Association.

Regarding the April 26 news article “ Massive volunteer-aided study reveals biggest known plastic polluters ”:

I was disappointed to read that U.S. negotiators at international meetings concerning plastic pollution have been resistant to an agreement that would limit plastic production.

I was a child in the 1940s, and I remember the milkman delivering milk in glass bottles to our house and retrieving the empty bottles for reuse. It was common practice. I drank my share of soft drinks then, but always from glass bottles. We have tried a plastic recycling approach for many decades, and it is apparent this is not working from an environmental perspective. It is time to phase back into the approach that was better for the environment by putting the emphasis on using, and reusing, glass. And if the glass cannot be reused, it can be recycled with a better outcome than trying to recycle plastic.

Robert F. Benson , Silver Spring

Bring back the birds

Regarding Dana Milbank’s April 28 Sunday Opinion essay, “ This tiny flower teaches us all we need to know about growing old ”:

I enjoy reading about Mr. Milbank’s adventures on his new homestead in Virginia’s Piedmont region. This essay about native wildflowers and tree planting was wonderful.

As an avid birdwatcher, I spent more than 20 years in Northern Virginia watching a lot of great habitat being bulldozed and turned into five-acre “estates," a fancy term for a fairly good-sized house with a lawn that was usually mowed down to the nubbin. One maple tree or dogwood would pass for landscaping. Often, streets in these neighborhoods would be named for the birds that used to live there but that no longer had places to nest and feed: Cardinal Court, Bluebird Lane, etc.

I hope Mr. Milbank’s essay will inspire more homeowners to plant trees and wildflowers that are native instead of invasives such as Bradford pears, which are illegal in a growing number of states. This change could do wonders for all the birds that are under threat from increased development.

Rich Rieger , Schuylkill Haven, Pa.

Good for the EPA

Regarding the April 26 Economy & Business article “ EPA rules would slash pollution from power plants ”:

The Environmental Protection Agency’s new rules limiting coal-fired power-plant emissions will ensure that the United States remains competitive in the renewable-energy economy as well as protect human health and all life. The power industry and its friends have protested that the new rules will be “unrealistic” and “unachievable” and don’t allow enough time to comply. But this argument ignores the fact that the industry has dragged its feet in reducing emissions in the 15 years since the EPA labeled greenhouse gases a health hazard.

Moreover, the power and fossil-fuel industries have both wasted decades of precious time since scientists concluded fossil fuel emissions drive climate change. Given the “pro-life” Republican Party’s opposition to alleviating this threat to life, the outcome of November’s election could very well determine whether power plants will finally clean up their acts — or climate change will be “baked in” to our future.

Michael Wright , Glen Rock, Pa.

About letters to the editor

The Post welcomes letters to the editor on any subject, especially those that expand upon the ideas raised by published pieces and those that raise valuable questions about The Post’s practices and choices. Letters should run no more than 400 words, be submitted only to the Post and must be published under your real name. Submit a letter .

share this!

May 7, 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

peer-reviewed publication

Researchers study the intricacies of homologous recombination and abnormal chromosome bridges

by Kindai University

Keeping the genetic information stored in genomic DNA intact during the cell division cycle is crucial for almost all lifeforms. Extensive DNA damage invariably causes various adverse genomic rearrangements, which can lead to cell death in the best cases and to the occurrence of diseases like cancer in the worst cases.

Fortunately, cells in all three domains of life share a peculiar error-free mechanism for maintaining genetic information, known as homologous recombination (HR).

The process of HR starts when a cell encounters DNA damage during DNA synthesis or afterwards, initiating a cascade of events. The damaged DNA is first resected or cut to create single-stranded ends near the damaged site. These ends are then matched to their corresponding region in an available replicated chromosome, also known as "sister chromatid," which is essentially used as a template to repair the damaged DNA.

As one might expect, the HR pathway involves a myriad of proteins and cellular machinery. While most of these proteins and cellular machinery are well-studied, some of them remain somewhat enigmatic. Such is the case of the regulators of RAD51, a protein responsible for repairing DNA double-strand breaks.

Normally, RAD51 forms filaments that help preserve DNA replication forks—transient arrangements of DNA that often occur during DNA replication, such as in replication fork collapse. Proper regulation of RAD51, as well as the degradation of these filaments after their purpose has been served, is essential for HR.

However, the precise mechanisms by which abnormal RAD51 accumulation leads to genetic instability are not completely understood, and many positive and negative RAD51 regulators remain obscure.

Now, however, in a recent article published in Nucleic Acid Research on 10 April 2024, a research team led by Professor Miki Shinoara from the Department of Advanced Bioscience, Kindai University, Japan, investigated the close relationship between RAD51 and FIGNL1, one of its key regulators. The study was co-authored by Kenichiro Matsuzaki, also from the Department of Advanced Bioscience, Kindai University, and sheds some much-needed light on the intricacies of the HR process.

First, the researchers genetically engineered human cells that did not express FIGNL1 (that is, FIGNL1 KO cells), using the well-established CRISPR/Cas9 method. Then, using advanced immunostaining techniques involving carefully selected antibodies and fluorescence microscopy , they visualized the HR process in detail, looking for indicators of abnormalities.

By combining this approach with a plethora of other experimental procedures, such as western blotting, cell cycle analysis, protein assays, and genomic and transcriptomic analyses, they managed to get a comprehensive picture of what happens in a cell when FIGNL1 is missing.

The results reveal that FIGNL1 is a highly specialized RAD51-dismantling enzyme that is necessary for proper chromosome separation after replication forks are "disassembled."

More specifically, when RAD51 filaments are not fully dismantled, abnormal events occur during mitosis that produce unresolved intermediates. This ultimately leads to the formation of so-called 'chromosome bridges' between the sister chromatids. These ultra-fine structures are very detrimental to the normal operation of the cell, causing the propagation of catastrophic genetic information.

Understanding the finer details of the HR pathway, its key players, and its many sub-processes is extremely important not only from a biological perspective, but also from a medical standpoint.

"Cell death due to dysregulation of HR is an important mechanism by which anticancer drugs exhibit cancer cell-specific cytotoxicity," explains Prof. Shinohara. "Until now, the main target has been HR activation deficiency, but the results of this study show that persistent activation of RAD51 also exhibits cytotoxicity and can be a molecular target for anticancer drugs."

Moreover, the cellular machinery involved in the HR pathway can be leveraged as a powerful bioengineering tool.

"HR is a well-conserved system among most species and is also tightly connected to gene modification technologies, such as genome editing and gene targeting technologies," comments Prof. Shinohara, "Thus, elucidating the mechanisms that control recombinase activity, such as that of RAD51, may contribute to increasing the efficiency of gene modification techniques."

Worth noting, genetic engineering is a highly effective avenue for increasing crop yield and for customizing microbial organisms for tasks such as bioremediation, which addresses various modern world problems.

Overall, the findings of this study not only shed light on a universal biological process but also pave the way toward a better understanding of cellular mechanisms for important drug discoveries and progress in the field of genetic engineering.

Journal information: Nucleic Acid Research , Nucleic Acids Research

Provided by Kindai University

Explore further

Feedback to editors

Team develops an epigenome editing toolkit to dissect the mechanisms of gene regulation

Every drop counts: New algorithm tracks Texas's daily reservoir evaporation rates

13 hours ago

Genetic study finds early summer fishing can have an evolutionary impact, resulting in smaller salmon

15 hours ago

Researchers discovery family of natural compounds that selectively kill parasites

Study suggests heavy snowfall and rain may contribute to some earthquakes

16 hours ago

The spread of misinformation varies by topic and by country in Europe, study finds

Webb presents best evidence to date for rocky exoplanet atmosphere

Human activity is making it harder for scientists to interpret oceans' past

Quantum simulators solve physics puzzles with colored dots

Chemists produce new-to-nature enzyme containing boron

Relevant physicsforums posts, who chooses official designations for individual dolphins, such as fb15, f153, f286.

4 hours ago

Is it usual for vaccine injection site to hurt again during infection?

17 hours ago

The Cass Report (UK)

May 1, 2024

Is 5 milliamps at 240 volts dangerous?

Apr 29, 2024

Major Evolution in Action

Apr 22, 2024

If theres a 15% probability each month of getting a woman pregnant...

Apr 19, 2024

More from Biology and Medical

Related Stories

Newly discovered protein prevents DNA triplication

Mar 4, 2024

Understanding why BRCA2 is linked to cancer risk

Apr 3, 2023

Making safe choices: DNA repair mechanisms avoid chromosomal combinations predisposed to disease

Apr 30, 2020

Scientists reveal how proteins team up to repair DNA

Mar 24, 2020

Yeast screen uncovers genes involved in chromosomal mutation

May 26, 2023

DNA replication discovery opens paths to understanding and treating cancer, aging and degenerative disease

May 3, 2023

Recommended for you

Researchers map out anatomy of wooden breast syndrome in broiler chickens

18 hours ago

An adjuvant made in yeast could lower vaccine cost and boost availability

19 hours ago

Marine bacteria team up to produce a vital vitamin

Study pinpoints cellular response to pressure in sea star embryos

Let us know if there is a problem with our content.

Use this form if you have come across a typo, inaccuracy or would like to send an edit request for the content on this page. For general inquiries, please use our contact form . For general feedback, use the public comments section below (please adhere to guidelines ).

Please select the most appropriate category to facilitate processing of your request

Thank you for taking time to provide your feedback to the editors.

Your feedback is important to us. However, we do not guarantee individual replies due to the high volume of messages.

E-mail the story

Your email address is used only to let the recipient know who sent the email. Neither your address nor the recipient's address will be used for any other purpose. The information you enter will appear in your e-mail message and is not retained by Phys.org in any form.

Newsletter sign up

Get weekly and/or daily updates delivered to your inbox. You can unsubscribe at any time and we'll never share your details to third parties.

More information Privacy policy

Donate and enjoy an ad-free experience

We keep our content available to everyone. Consider supporting Science X's mission by getting a premium account.

E-mail newsletter