October 1, 2008 Engineers processed data from NASA's Aura satellite in order to track and predict the movement of airborne pollution. Using satellite data to measure ozone concentrations over time allows scientists and engineers to improve their models. This enables them to better their predictions and issue more accurate forecasts of pollution movement and concentration.
Every day, we count on information from satellites to guide the GPS in our cars, track approaching hurricanes, or just tell us what the weather will be like tomorrow -- but could satellite data also help protect us from pollution that could be hazardous to our health? That's what researchers are trying to find out.
As long as he's at the beach -- renting bikes and not cars -- Charlie Shaw doesn't worry much about air pollution.
"It's not a thought to me, because 90 percent of the time the wind is coming off the ocean and there's really not much out there," says Shaw.
In most major cities though, ground-level ozone and pollution from other sources is something to worry about -- and closely monitor to protect public health.
But what about areas where there is traffic and industry, but no air pollution monitors?
Environmental fluid dynamicist Joseph Fernando, Ph.D., says with growing industry along the Mexican border, air quality is getting worse -- but there hasn't been a way to monitor it. Now, his engineering research team is using satellite data to improve computer models that help predict pollution levels.
"So we can get information today and start the model today," says Dr. Fernando, who works at Arizona State University in Tempe, Ariz.
Instruments on NASA's aura satellite help researchers predict the height of air pollution particles. On an hour-by-hour basis, unhealthy events show up in red. Because these computer models can predict pollution movement and concentration in specific areas, health warnings can be issued hours in advance.
"If you have prediction tonight, then in the evening you can put out a warning for tomorrow," says Dr. Fernando. In the years ahead, satellites could be key to understanding ozone worldwide to protect public health -- and help us all breathe easier.
WHAT IS SMOG? Smog is a mixture of air pollutants that form smoke and fog in the air. It is generally formed when ground-level ozone, fine particles, and other chemicals react on hot days. Ozone in the upper atmosphere protects the Earth from the sun's harmful ultraviolet rays, but at ground level, ozone is a highly irritating gas. It forms when two primary pollutants -- nitrogen oxides and volatile organic compounds -- react in sunlight and stagnant air. Most nitrogen oxides come from burning fossil fuels, while VOCs are gases that contain carbon, usually emitted by gasoline fumes and solvents, such as those found in some paints. Airborne particles, sometimes called aerosols, are microscopic particles of pollutants that can remain suspended in the air for a considerable length of time. Primary particles include windblown dust and soil, sea spray, pollen, and plant spores.
ABOUT OZONE: Ozone is a minor constituent in our atmosphere; there are about three molecules of ozone per every 10 million air molecules, and yet it plays a vital role in human health. Most ozone (90%) can be found in an upper layer of the earth's atmosphere called the stratosphere. It is beneficial because it absorbs most of the damaging ultraviolet sunlight, which can cause skin cancers, among other conditions. The remaining 10% of ozone can be found in a lower region called the troposphere. Here, it reacts with other molecules to produce smog, which has toxic effects on crops, forest growth, and human health.
SMOG MAKES BREATHING DIFFICULT: Smog can make breathing difficult and can make human beings more susceptible to cardio-respiratory diseases. People already suffering from heart or lung disease are particularly affected. The two main ingredients in smog that affect human health are ground-level ozone and fine airborne particles.
The American Meteorological Society and the American Geophysical Union contributed to the information contained in the TV portion of this report.