Subscribe

Satellite imagery helps NASA find unreported sources of air pollution

In a recent collaborative study, NASA, along with Environment and Climate Change Canada and two universities, located major previously unknown sources of air pollution.

  • close
    Exhaust rises from smokestacks in front of piles of coal at NRG Energy's W.A. Parish Electric Generating Station in Thompsons, Texas, in March 2011. Images from NASA's Aura Spacecraft have helped researches locate 39 severe and unreported man-made sources of toxic sulphur dioxide emissions coming from such sources as power plants and other industrial facilities.
    David J. Phillip/AP/File
    View Caption
  • About video ads
    View Caption
of

In parts of the Middle East, Russia, and Mexico, the air is more polluted by factories and power plants than previously thought. 

NASA, in conjunction with Environment and Climate Change Canada and two independent universities – The University of Maryland, College Park and Dalhousie University in Halifax, Nova Scotia – has located 39 severe and unreported man-made sources of toxic sulfur dioxide emissions.

Sulfur dioxide (SO2), one of the six air pollutants regulated by the US Environmental Protection Agency – along with carbon monoxide, ground-level ozone, lead, nitrogen oxides, and particulate matter – is one of a group of highly reactive gases known as "oxides of sulfur," according to the EPA. The greatest contributor of SO2 emissions into the air comes from large-scale fossil fuel combustion, such as that at power plants and other industrial facilities. Lesser contributors include large-ships, locomotive engines, and nonroad equipment.

While reporting on SO2 emissions has been ground-based, gathered from statistics such as fuel usage, the most recent method developed by the collaboration of scientists utilized satellite imagery to locate massive and previously unreported or underreported contributors of SO2 into the air.

"When you look at a satellite picture of sulfur dioxide, you end up with it appearing as hotspots – bull's-eyes, in effect – which makes the estimates of emissions easier," said Chris McLinden, an atmospheric scientist with Environment and Climate Change Canada, as well as the primary author of the recently published study in Nature Geosciences. "We now have an independent measurement of these emission sources that does not rely on what was known or thought known."

Combined, the 39 unreported or underreported sulfur dioxide sources, which were found mostly in the Middle East and around the Persian Gulf – though also in parts of Russia and Mexico – contribute roughly 12 percent of all human-related SO2 emissions. That discrepancy can have a massive impact on regional air quality, according to Mr. McLinden. 

Sulfur dioxide is a pungent, irritating chemical which is directly related and even considered a precursor to acid rain as well as greater percentages of atmospheric particulates – solid and liquid particles such as dust, smoke, pollen, etc. that are suspended in air. Coal and oil-burning power plants contribute a great deal of SO2 into the air; however until recently, reporting exact numbers of SO2 emissions was problematic due to a lack of monitoring capabilities.

Now, utilizing raw satellite observations from an instrument aboard NASA's Aura Spacecraft, scientists are able to view these "hotspots" over time and make precise estimates of SO2 concentrations. The scientists were also able to track sulfur dioxide wind dispersion by accurately estimating wind strength and direction based on satellite information and were able to trace SO2 back to their sources and calculate how much had been omitted over a period of time.

Along with the 39 man-based SO2 emission sites found by the team of scientists, they also discovered 75 sources of natural sulfur dioxide emissions, many of which are located in remote and unmonitored locations; sites such as nonactive volcanoes which slowly leak previously unmeasured amounts of SO2 into the air. 

By utilizing these new techniques, scientists will be better able to monitor the amount of sulfur dioxide being emitted into the atmosphere – a potentially major environmental breakthrough.

About these ads
Sponsored Content by LockerDome
 
 
Make a Difference
Inspired? Here are some ways to make a difference on this issue.
FREE Newsletters
Get the Monitor stories you care about delivered to your inbox.
 

We want to hear, did we miss an angle we should have covered? Should we come back to this topic? Or just give us a rating for this story. We want to hear from you.

Loading...

Loading...

Loading...

Save for later

Save
Cancel

Saved ( of items)

This item has been saved to read later from any device.
Access saved items through your user name at the top of the page.

View Saved Items

OK

Failed to save

You reached the limit of 20 saved items.
Please visit following link to manage you saved items.

View Saved Items

OK

Failed to save

You have already saved this item.

View Saved Items

OK