Urban air pollution is linked to up to one million premature deaths each year. If you live in one of world's biggest and most heavily congested cities, the evidence of air pollution can be seen clearly outside your window--on a smoggy day, buildings once in plain sight can be completely blocked from view. But for those of us who live outside urban areas, the threat of air pollution is less obvious. Invisible to the naked eye, nitrogen dioxide and other air pollutants can be carried by the wind thousands of miles from their urban sources.
With the help of modern satellite technology and a project known as TEMIS, scientists are now measuring and mapping the concentrations and transboundary movements of air-polluting emissions. For the first time, anyone with an Internet connection can access near-real time satellite images of health-threatening pollutants. You can even download the data into Google Earth, which will project the images onto the globe in a series of short films.
Today's Tropospheric NO2 Observations over Asia
(26 Oct 2007)
Source: TEMIS, 2007
TEMIS, which stands for Tropospheric Emission Monitoring Internet Service, displays data for tropospheric ozone (O3), nitrogen dioxide (NO2), and sulfur dioxide (SO2), among other pollutants. Most data goes back as far as 2002.
Policy Implications
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, including those affecting motorized transport, which accounts for 90% of urban air pollution. 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.
A blogger from EMBARQ, the World Resources Institute's center for sustainable transport, recently reported on the upcoming 2008 release of the $2,500 Tata car in India. If you are wondering what impacts this ultra inexpensive car might have on Indian air quality, tune into TEMIS to watch the story unfold each day on your computer screen.
RELATED LINKS:
EMBARQ: the WRI Center for Sustainable Transport
World Bank information on urban air pollution (pdf)
EarthTrends
Emissions and air pollution data
News: The Most Polluted Cities in the World
News: Beijing Temporarily Bans Cars in Bid to Reduce Air Pollution
Monthly Update: Sustainable Transport in the Developing World
