Using satellites to map pollution. Photo by kennethg from Flickr.

With the help of satellites, scientists are now measuring and mapping concentrations and global movements of air-pollution and, through a cool new project known as TEMIS, have made near-real time satellite images of pollutants available online. TEMIS allows anyone with an internet connection to download its data into Google Earth, which projects the images onto the globe in a series of short films.

From a public health perspective, the TEMIS project is an incredibly powerful tool. These images are the first to provide a vertical profile of gas concentrations, meaning that we can now see how much pollution people are being exposed to on the ground. They also show us the immediate and long-term implications of emissions-related policy decisions. When Beijing temporarily removed one-third of its private vehicles from the road between 4 and 6 November 2006, for example, TEMIS registered a 40 percent reduction in nitrogen dioxide emissions. Ana Escalante recently reported on the upcoming 2008 release of the $2,500 Tata car in India. If you are wondering what impacts this super cheap car might have on Indian air quality, tune in to TEMIS to see the story unfold each day on your computer screen.

For more information, see a post I wrote for Earthtrends.