Air Quality Forecasts See Future in Space

Weather broadcasts have long been a staple for people planning their day. Now with the help of NASA satellites, researchers are working to broaden daily forecasts to include predictions of air quality, a feat that is becoming reality in some parts of the world.

Some scientists predict that an operational system of routine, global forecasts of air pollution near the ground, where it affects human health, is only a few years away. Such a system could prove useful in efforts to improve air quality, assess the effectiveness of environmental regulations and address the challenge of climate change. Advances in air quality monitoring and forecasts are being discussed this week at the American Geophysical Union meeting in San Francisco.

"Regional modeling is already getting quite meaningful," says Richard Engelen of the European Centre for Medium-Range Weather Forecasts in Reading, United Kingdom. He notes that air quality forecasts are now possible up to a few days in advance in Europe where there has been a concerted effort to combine atmospheric composition data from satellites and ground stations into the existing backbone of weather forecast computer models.

The European project – the Global and Regional Earth-system (Atmosphere) Monitoring Using Satellite and In-Situ Data project – is currently in the experimental stage. In the United States, planning for the application of satellite data in regional air quality forecast model is underway at the National Oceanic and Atmospheric Administration and the U.S. Environmental Protection Agency (EPA). But for forecasts to become more accurate and global, researchers need more and better observations, Engelen says. That's where NASA satellites are helping to fill in the gaps.

"To really do an accurate job of forecasting air quality, you have to know what pollution is coming in from upwind," says Kenneth Pickering of NASA Goddard Space Flight Center, Greenbelt, Md., who studies the chemistry and movement of gases through the atmosphere.

For example, a recent study conducted by researchers from NASA’s Langley Research Center, Hampton, Va., and Jet Propulsion Laboratory, Pasadena, Calif., used satellite instruments to look at air quality in Houston, Texas, a city with major air quality problems. Using data from two instruments on NASA's Aura satellite, researchers found that not all of Houston's pollution was locally caused and there was significant long-range transport from the Midwest and Ohio Valley. "Although the finding was made possible by a computer model, it was greatly aided by the Aura satellite data," Pickering says.

Researchers at centers including NASA Goddard Space Flight Center, Greenbelt, Md., are also experimenting with blending satellite ozone data with the output from computer models to continuously improve a forecast's accuracy.

NASA satellites are helping researchers evaluate the Clean Air Interstate Rule instituted in 2005 by the EPA. The rule calls for eastern U.S. power plants to cut sulfur dioxide and nitrogen oxide emissions by 73 and 60 percent, respectively, by 2018. Coal burning plants emit plumes containing sulfur dioxide and nitrogen oxides into the atmosphere, where they undergo chemical reactions and form aerosol particles that lead to adverse health impacts, degrade visibility and can influence Earth's climate. These aerosols are usually transported by wind away from their source to distant regions. Satellite instruments, as well as models and other information sources, allow researchers to create a history describing how much aerosol is transported and where, helping them to evaluate the rule.

"Satellites add considerable vertical and horizontal spatial detail, enabling a more scientifically sound way of understanding whether or not programs are making progress in reducing air pollution in the long term," says Rich Scheffe of the EPA in Research Triangle Park, N.C.

Satellite data still pose challenges, however, and researchers are trying to find ways to tease out specific information, such as how much of each gas exists at a specific altitude. This is a particularly challenging measurement to make in the air closest to Earth’s surface, where the information matters most relevant for air quality regulations. More research is needed to determine the value of the current data and to develop improved sensors for future satellites, Pickering says.

The advances in forecasting air quality are happening fast, spurred in part by concern about global warming. At Earth's surface, warmer temperatures can accelerate the reaction between chemicals in the air that form ozone. "The combination of the increase of transported air pollution and the interaction of climate change and air quality really puts a greater premium on satellite imagery for air quality applications," Scheffe says.

Source: by Kathryn Hansen, NASA's Goddard Space Flight Center

Related stories:

Google-sponsored satellite sends first image
A Google-sponsored satellite has beamed its first picture back to Earth in a successful test of a camera that will supply images for the Internet giant's free online map and navigation services.
IU sends innovative technology to Antarctica to speed polar research
Environmental scientists studying the world's shrinking polar ice sheets will soon get a substantial boost in computing power thanks to IU's Polar Grid Project.
Smoke smudges Mexico City's air, chemists identify sources
Mexico City once topped lists of places with the worst air pollution in the world. Although efforts to curb emissions have improved the situation, tiny particles called aerosols still clog the air. Now, atmospheric scientists from UC San Diego and six other institutions have sorted through the pall that hangs over the city to precisely identify aerosols that make up the haze and chart daily patterns of changes to the mix.
Warmer seas linked to strengthening hurricanes
The theory that global warming may be contributing to stronger hurricanes in the Atlantic over the past 30 years is bolstered by a new study led by a Florida State University researcher. The study will be published in the Sept. 4 edition of the journal Nature.
Living with a Star
What if you woke up one morning and found your whole planet had been swallowed by the atmosphere of a star?
Ocean Surface Topography Mission/Jason 2 Begins Mapping Oceans
(PhysOrg.com) -- Less than a month after launch, the NASA-French space agency Ocean Surface Topography Mission (OSTM)/Jason 2 oceanography satellite has produced its first complete maps of global ocean surface topography, surface wave height and wind speed.
Air Quality Forecasts for China
With less than a month remaining before the Beijing Olympics, Chinese officials have introduced a series of measures to improve air quality for the Games. A new tool has been installed in the capital city to allow the Chinese to monitor the effectiveness of these efforts.
Many processors make light work of calculations
Solving complicated calculations has never been easy, but a new European computing grid means researchers can number crunch their data faster than ever before.

News discussion:

Space & Earth science news