The European Space Agency satellite Envisat contains a unique measurement device SCIAMACHY short for Scanning Imaging Absorption Spectrometer for Atmospheric Chartography. This imaging spectrometer records the spectrum of sunlight shining through the atmosphere and has been performing global measurements of trace gases in the troposphere and stratosphere for over four and a half years.

Man made pollution is one of the largest dangers for the future of the earth. Too much Nitrogen Dioxide (NO2) is a health hazard which causes lung damage and health problems. Measurements are made from ground level to heights of tens of kilometers.

Large amounts of NO2 pollution are hanging over Beijing and north east China and large amounts of the green house gas methane have been discovered over the Ganges valley in India. Atmospheric satellite data now spans over a decade. Satellites help tell us which countries are delivering on their promises to reduce green house gas emission and air pollution. This data can guide action now. http://www.esa.int/esa-mmg/mmg.pl?type=V key word SCIAMACHY