Based on three years of observations from the SCIAMACHY instrument aboard ESA's Envisat, scientists have produced the first movies showing the global distribution of the most important greenhouse gases carbon dioxide and methane that contribute to global warming.
The importance of cutting emissions from these 'anthropogenic', or manmade, gases has been highlighted recently with European Union leaders endorsing binding targets to cut greenhouse gases by at least 20 percent from 1990 levels by 2020. Further illustrating the urgency to combat global warming, Britain became the first country last week to propose legislation for cutting the gases.
Careful monitoring is essential to ensuring these targets are met, and space-based instruments are new means contributing to this. The SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Chartography) instrument, for instance, is the first space sensor capable of measuring the most important greenhouse gases with high sensitivity down to the Earth's surface because it observes the spectrum of sunlight shining through the atmosphere in 'nadir' looking operations.
Dr. Michael Buchwitz and Oliver Schneising from the Institute of Environmental Physics (IUP) at the University of Bremen in Germany, led by Prof. Dr. John P. Burrows produced these maps based on SCIAMACHY observations from 2003 to 2005.
Although carbon dioxide is the most important greenhouse gas, methane molecules trap heat with an efficiency that is 20 times larger than that of a molecule of carbon dioxide. Also, emissions from methane the second most important greenhouse gas may significantly rise in the future due to global warming if methane is released from currently frozen permafrost areas.
The new methane data also confirm findings from another study in 2005 carried out by the Institute of Environmental Physics (IUP) at the University of Heidelberg in cooperation with the Royal Netherlands
Contact: Mariangela D'Acunto
European Space Agency