NASA satellite confirms sharp decline in pollution from US coal power plants

December 1, 2011, NASA's Goddard Space Flight Center
NASA satellite confirms sharp decline in pollution from US coal power plants
This map shows average sulfur dioxide levels measured by the Aura satellite for the period 2008-2010 over a portion of the eastern United States. The black dots represent the locations of many of the nation's top sulfur dioxide emissions sources. Larger dots indicate greater emissions. Credit: Credit: NASA's Earth Observatory

A team of scientists have used the Ozone Monitoring Instrument (OMI) on NASA's Aura satellite to confirm major reductions in the levels of a key air pollutant generated by coal power plants in the eastern United States. The pollutant, sulfur dioxide, contributes to the formation of acid rain and can cause serious health problems.

The scientists, led by an Environment Canada researcher, have shown that levels in the vicinity of major coal have fallen by nearly half since 2005. The new findings, the first of this type, confirm ground-based measurements of declining sulfur dioxide levels and demonstrate that scientists can potentially measure levels of throughout the world, even in places where ground monitoring is not extensive or does not exist. About two-thirds of sulfur dioxide pollution in American air comes from coal power plants. published details of the new research this month.

The scientists attribute the decline in sulfur dioxide to the Clean Air Interstate Rule, a rule passed by the U.S. in 2005 that called for deep cuts in sulfur dioxide emissions. In response to that rule, many power plants in the have installed desulfurization devices and taken other steps that limit the release of sulfur dioxide. The rule put a cap on emissions, but left it up to power companies to determine how to reduce emissions and allowed companies to trade pollution credits.

While scientists have used the Ozone Monitoring Instrument to observe sulfur dioxide levels within large plumes of and over heavily polluted parts of China in the past, this is the first time they have observed such subtle details over the United States, a region of the world that in comparison to fast-growing parts of Asia now has relatively modest sulfur dioxide emissions. Just a few decades ago, sulfur dioxide pollution was quite severe in the United States. Levels of the pollutant have dropped by about 75 percent since the 1980s due largely to the passage of the Clean Air Act.

Vitali Fioletov, a scientist based in Toronto at Environment Canada, and his colleagues developed a new mathematical approach that made the improved measurements a reality. The approach centers on averaging measurements within a 30 miles radius (50 km) of a sulfur dioxide source over several years. "Vitali has developed an extremely powerful technique that makes it possible to detect emissions even when levels of sulfur dioxide are about four times lower than what we could detect previously," said Nickolay Krotkov, a researcher based at NASA's Goddard Space Flight Center in Greenbelt, Md., and a coauthor of the new paper.

The technique allowed Fioletov and his colleagues to pinpoint the sulfur dioxide signals from the 40 largest sulfur dioxide sources in the United States – generally coal power plants that emit more than 70 kilotons of sulfur dioxide per year. The scientists observed major declines in sulfur dioxide emissions from power plants in Alabama, Georgia, Indiana, Kentucky, North Carolina, Ohio, Pennsylvania and West Virginia by comparing levels of the pollutant for an average of the period 2005 to 2007 with another average from 2008 to 2010.

"What we're seeing in these satellite observations represents a major environmental accomplishment," said Bryan Bloomer, an Environmental Protection Agency scientist familiar with the new satellite observations. "This is a huge success story for the EPA and the Clean Air Interstate Rule," he said.

The researchers focused their analysis on the United States to take advantage of the presence of a robust network of ground-based instruments that monitor inside power plant smokestacks. The ground-based instruments have logged a 46 percent decline in sulfur dioxide levels since 2005 – a finding consistent with the 40 percent reduction observed by OMI.

"Now that we've confirmed that the technique works, the next step is to use it for other parts of the world that don't have ground-based sensors," said Krotkov. "The real beauty of using satellites is that we can apply the same technique to the entire globe in a consistent way." In addition, the team plans to use a similar technique to monitor other important pollutants that plants release, such as nitrogen dioxide, a precursor to ozone.

OMI, a Dutch and Finnish built instrument, was launched in 2004, as one of four instruments on the Aura satellite, and can measure sulfur dioxide more accurately than any satellite instrument flown to date. Though OMI remains in very good condition and scientists expect it to continue producing high-quality data for many years, the researchers also hope to use data from an upcoming Dutch-built OMI follow-on instrument called TROPOMI that is expected to launch on a European Space Agency satellite in 2014.

On July 6, 2011, the U.S. Environmental Protection Agency (EPA) finalized the Cross-State Air Pollution Rule (CSAPR), requiring 27 states to significantly reduce power plant emissions that contribute to and fine particle pollution in other states. This rule replaces EPA's 2005 Clean Air Interstate Rule (CAIR). A December 2008 court decision kept the requirements of CAIR in place temporarily but directed EPA to issue a new rule to implement Clean Air Act requirements concerning the transport of air pollution across state boundaries. This action responds to the court's concerns.

Explore further: EPA says sulfur dioxide emissions are down

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5 / 5 (6) Dec 01, 2011
Just keep it going!
Cleaning up what we have is not a burden nor an impossibility! Acting responsibly can unfetter new technologies that make jobs AND saves lives. This kind of restriction in ongoing, yes, ONGOING emissions is proof that the tech and the WILL to make a ecological difference does not have to wait for a Buck Rogers future. We start now & we get better with newer energy production while learning to recycle waste & reusable substances. This IS a very good first effort and a positive beginning 2 humanity's effort to take care of the only planet we know of in the universe that supports life and particularly, OUR life/lives. We can do better, Yes, we can...YES we can...
0.6 / 5 (46) Dec 01, 2011
These filthy communists at the EPA have done nothing but mount a full fledged campaign to destroy America.

And these methods/models are by whom?

"Vitali Fioletov, a scientist based in Toronto at Environment Canada"

A commie name if ever I saw one, working in a commie nation that is enslaving it's people with government run healthcare.

Government run health care is pure slavery.


The EPA is pure communism....

5 / 5 (6) Dec 01, 2011
@vendicar, if you are only kidding, you need to hint at it. If you are not kidding, wow.
0.4 / 5 (39) Dec 01, 2011
Interesting isn't it that you can't tell if I'm pretending to be an American ConservaTard or am a real one.

That is how far main stream Conservatives like Ron an Rand Paul - elected by the American people - have detached themselves from reality.

0.4 / 5 (39) Dec 01, 2011
You should check out Rand Paul's complaints in congress of how his turds are too big to flush with the new toilets that the evil gubderment forced him to purchase under penalty if imprisonment.

His congressional statement brought a tear to my eye.

Mostly out of laughter, and a little out of pity for a mind so polluted by his KookTard father and the anti-state nattering of government welfare queen Ayn Rand.

2 / 5 (5) Dec 01, 2011
3 / 5 (6) Dec 01, 2011
Piroutte makes a good post but it's EPA Laws that have forced coal burning plants (yes R2 real regulations) to reduce sulfur emissions to reduce forest killing acid-rain. So it's nice the link to the DOE website on how coal plants can be made clean.

I can only guess the Pirouette is somehow financially supported by coal, but that aside. If the CO2 from coal burning is sequestered, then great problem global warming issue solved.
If CO2 from coal could be recombined with hydrogen to make hyrdro-carbon fuels, great global warming can be delayed by getting twice the ride out of the same CO2.

Coal is nasty anyway. Best to phase it out of use for the green alternatives.

0.6 / 5 (40) Dec 02, 2011
We already have the surface of the earth covered in machines that sequester CO2.

They are called plants. They are the best nature could evolve over the last 3 billion years, and they aren't doing the job.
2.3 / 5 (6) Dec 02, 2011
Coal in and of itself isn't a nasty substance. It's the particulates that do the most damage to everything they land on. Black lung disease suffered by miners is almost always fatal. But air scrubbers, if improved even more than now, could capture ALL of the particulate matter AND at least most of the gases. Air scrubbers are used in submarines, which eliminates almost all of the CO2 and, I believe, releases the filtered Oxygen part back into the air. But a submarine has very little particulate matter in its air supply, so it's quite safe.
1.8 / 5 (5) Dec 02, 2011
Plants would do the job if they weren't cut down so fast and consistently. Cities have bad air due to less plant life, that's a given, in spite of all the AC in the skyscrapers. And there are certain plants that are really great at taking up pollution and CO2 in a room and putting Oxygen back, but not enough people buy those types or are unaware of them. And most air filters are inadequate to filtering ALL particulate matter.
1 / 5 (6) Dec 02, 2011
Not to mention all the pollution caused by cigarette smoke. All kinds of excuses for not stopping smoking. . .then, if they develop a bad cough and the doctor says it'a cancer, they will quit outright when it's too late. I never could understand that
5 / 5 (3) Dec 02, 2011
I think you guys should lighten up on pirouette's ratings here. Whatever he's like else where, most of what he provided for this article is here is useful and relavent, aside from his last two comments.

While 'clean coal' is certainly not yet completely proven, it has enough promise that it is certainly worth pursuing. If we can make all our coal plants clean while we finish implementing renewables and other energy sources, then why not do it? There are no economic models or plans to convert to renewables that believe we can completely phase out coal until another 30-40 years go by. so lets do the best with what we have, in addition to moving away from fossils.

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