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The Best Science Writing Online 2012
Showcasing more than fifty of the most provocative, original, and significant online essays from 2011, The Best Science Writing Online 2012 will change the way...
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The acid rain scourge of the '70s and '80s that killed trees and fish and even dissolved parts of statues on Washington, D.C.'s National Mall is back. But unlike the first round, in which sulfur emissions from power plants mixed with rain to create sulfuric acid, the current problem stems primarily from nitrogen emissions mixed with rain to create nitric acid.
"Both are strong acids, and both create serious problems for the environment," says William Schlesinger, president of the Cary Institute for Ecosystem Studies in Millbrook, N.Y. Acid rain degrades cement and limestone as well as leaches critical soil nutrients, which injures plants. It also liberates toxic minerals from the ground that flow into stream runoff where they can kill fish.
Sulfur emissions from power plants were one of the primary motivations for the U.S.'s Clean Air Act Amendments of 1990, which set reduction targets for both sulfur dioxide (SO2) and nitrogen oxides (NOx). However, whereas sulfur dioxide emissions decreased almost 70 percent from 1990 to 2008, emissions of one NOx—nitrogen dioxide (NO2)—went down only 35 percent for that same period, and amendment targets have yet to be made, according to the U.S. Environmental Protection Agency (EPA). "This comes as scientists have grown increasingly aware of the consequences of the remaining nitric acid deposition," Schlesinger says.
Schlesinger is one of a number of scientists calling attention to the problem. On June 8 the Integrated Nitrogen Committee of the EPA's Science Advisory board held a public teleconference to discuss a draft report of possible solutions to nitrogen problems, including acid rain. A final report is pending.
Nitric acid rain is derived primarily from power plant, car and truck emissions as well as from gases released by fertilizer use. Part of the problem dates back to WWI, when two German scientists invented the Haber–Bosch process, which took nonreactive nitrogen from the air (N2) and converted it into reactive, usable ammonia (NH3). Most of the nitrogen harvested via this process has been used in fertilizers, and the runoff from farms has created dead zones in Chesapeake Bay and at the mouths of the Columbia and Mississippi rivers. Some efforts have been made to regulate the agricultural nitrogen runoff, but atmospheric emissions of agricultural ammonia remain virtually unrestricted.
Agri-ammonia vapors also derive from concentrated animal feeding operations in the U.S. South. The gas rises into the air and is deposited dry or in rainfall where in the ground bacteria breaks it into nitrogen and nitric acid, which can kill fish and plants. "Agriculture is increasingly functioning as an intensively managed industrial operation, and that is creating serious water, soil, and air problems," says Viney Aneja, a professor at North Carolina State University in Raleigh. Aneja says that state's concentrated animal feeding operations may also emit particulate matter from swine and chicken manure into the atmosphere, which can carry diseases.
NOx escapes from power plants as a by-product of coal combustion, whereas vehicular engines run at high enough pressures and temperatures to combine nitrogen and oxygen in the air. "Though catalytic converters have decreased the amount of pollution per vehicle, there are more vehicles on the road and more miles driven," Schlesinger says. Emissions from fertilizers are the chief source of atmospheric nitric oxide, but motor vehicles have now overtaken coal power plants as the secondary most critical source of this problem.
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13 Comments
Add CommentIf we are forbidden to excrete even Nitrogen, how could we live on Earth.
Reply | Report Abuse | Link to thisWe can (we will) live at population levels that do not cause all these problems. The question is, how will we get there? Forced by Nature, or through a reasoned effort that minimises human suffering?
Reply | Report Abuse | Link to thisKonkon, how can we Europeans live on Earth with smaller nitrogen emissions?
Reply | Report Abuse | Link to thisOh, I forgot, we don't have humvees and 30 year old muscle cars with no catalytic converters.
We are indeed producing pollutants which I very much wish to see eradicated but those of you who think that this is about anything but money and power are naive. If mankind were truly able to significantly adversely affect earth's environment as a whole, we would have destroyed ourselves long ago and good old mother earth would be doing nicely now and would even have forgotten we were ever here. We can all talk about cleaning up the planet and showing concern over poisoning our environment with each new discovery, but the truth is that the big money will do what they want, where they want and when they want. Some, like Dimitris will blame it on some other country when the people who live there have absolutely no say in the matter, but you will hate them anyway.
Reply | Report Abuse | Link to this"Care for her and all her creatures"
Reply | Report Abuse | Link to thisthink about this!
Daily think about this
Reply | Report Abuse | Link to this"Care for her and all her creatures"
Before I changed my major to geology it was sociology & my interest remains. One of the papers I read on the failure of companies to allow their employees to work from hone ( the big benefit of the internet) was that bosses were dissatisfied without the employees present regardless of the accomplished work. There seems to be a necessary ego stroke in the requirement that employees be physically present, a psychological necessity in our social system. After all, what is religion but a congregation of compliant bodies.
Reply | Report Abuse | Link to thisSchlesinger says. Emissions from fertilizers are the chief source of atmospheric nitric oxide, but motor vehicles have now overtaken coal power plants as the secondary most critical source of this problem.
Reply | Report Abuse | Link to thisRemember that when the Amish farms around Chessie are in the news again. It is artificial fertilizer that is the problem. Electric cars would just allow more coal power plants creating a see-saw between cars & coal plants. And the coast to coast diesel rig transports aren't going to stop, are they? And planes are third?
That is of course common sense. But a half century of common sense hasn't halted progress. I looked up Rube Goldberg on Wiki & it seems other countries saw this simplification-into-complexity coming also.
Reply | Report Abuse | Link to thisI have several Knols which comment on this. I suspect we are merely mutations which have found a niche; our predators exist, they are the virus & bacteria & they need a dense population to do their work.
Please provide a citation for the Uni. of Minnesota study you quote in the article.
Reply | Report Abuse | Link to thisNavdoc is right, it's always about the money and how long can they keep on making that money without being stopped.
Reply | Report Abuse | Link to thisBring back the small farms, that would end unemployment, feed the nation and stop the pollution from mega factory farms.
But not to worry, there is a solution to all of it coming very soon.
A change is happening as we speak.
A better, safer and more productive fertilizer has been created. Smaller farms are coming back as organics, and in the end the people will win.
Can't fool all the people, all the time, even if you do advertise on TV 24/7.
Why is that there is all this reporting of things happening to the Earth and problems that are potentially devastating to the people and the environment by scientists but when they are asked why or what is going on they don't know?
Reply | Report Abuse | Link to thisHow are they reporting these things but don't understand them?
Are the scientist just stupid and pretending to be working?
Or are they in over their heads and need to be out painting billboards instead of in a science lab?
Or don't they read their own studies?
An example:
"It's clear that humans are adding nitrogen to Earth's surface. Researchers do not know yet where it all goes, "but we do know that increasing concentrations of nitrogen in unexpected places will cause significant environmental damage that we will all learn to regret," Schlesinger wrote in a 2009 report in Proceedings of the National Academy of Sciences."
But then who can question scientists who have all kinds of degrees? Of course when this happens in medical science, they always say, "we don't know what the appendix does, but it's ok to remove it. It must not do anything if we can't figure out what purpose it serves."
Never fails. They do it all the time, for decades, till somebody says, "Hey, it does do something and we better leave it alone!"
Bunch of educated fools, all of them.
And don't question me, I have a couple of degrees too!
Did you read the article, because that is where the quotation came from.
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