"By comparing model results with satellite observations (assuming that most differences are primarily due to shortcomings of our current knowledge that has been included in the model), the model is continually adjusted until it is able to reproduce the satellite observations as closely as possible," Buchwitz said. "Based on this, we continually improve the model and our knowledge of nature."

Data from SCIAMACHY is being provided to the GMES Service Element for Atmosphere PROMOTE, which delivers policy-relevant services on multiple atmospheric issues to end-users. Feedback from these users is helping the scientists at the University of Bremen to improve their algorithms further, which is essential for reaching the accuracy level of 1 percent needed for SCIAMACHY to retrieve information on greenhouse gas sources and sinks.

Buchwitz and his colleagues used SCIAMACHY data from the same period to retrieve the columns of carbon dioxide, which occurs naturally as well as being created through human activities, such as the burning of fossil fuels.

As with methane, there are significant gaps in the knowledge of carbon dioxide's sources, such as fires, volcanic activity and the respiration of living organisms, and its natural sinks, such as the land and ocean.

By better understanding all of the parameters involved in the carbon cycle, scientists can better predict climate change as well as better monitor international treaties aimed at reducing greenhouse gas emissions, such as the Kyoto Protocol which addresses the reduction of six greenhouse gases including methane and carbon dioxide.

With climate change being the greatest environmental challenge facing the world today, numerous studies and results on greenhouse gases will be presented at the 2007 Envisa
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Contact: Mariangela D'Acunto
mariangela.dacunto@esa.int
39-069-418-0856
European Space Agency
20-Mar-2007