ESA produces first animated shots of greenhouse gas distribution
The first films to map out the global atmospheric distribution of carbon dioxide (CO2) and methane (CH4) - two very potent greenhouse gases that are considered to be key contributors to global climate change - have been released by the European Space Agency (ESA). The maps are based on three years of observations by SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Chartography), the first ever space sensor capable of measuring greenhouse gases directly down to the Earth's surface. SCIAMACHY is part of the atmospheric chemistry payload on board ESA's ENVISAT satellite. Its job is to observe the way sunlight is transmitted, reflected and scattered by the Earth´s atmosphere or surface. This information is then used to provide data on the distribution of important atmospheric constituents, such as carbon dioxide and methane. These are responsible for absorbing or scattering light, as well as the spectral reflectance of the Earth's surface. Scientists believe that these maps will fill in important gaps in our knowledge about how greenhouse gases are distributed across the globe. '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,' said Michael Buchwitz from the Institute of Environmental Physics (IUP) at the University of Bremen in Germany. Dr Buchwitz is one of the scientists involved in producing the maps. 'Based on this, we continually improve the model and our knowledge of nature,' he added. Already the data, which was collected by SCIAMACHY between 2003 and 2005, has helped the Bremen team to improve the accuracy of their algorithms. Data from the sensor has also enabled the scientists to distinguish between columns of manmade CO2, such as the burning of fossil fuels, and the naturally occurring gas. It is likely that the maps will help shed further light on the different methane sources and sinks. The maps will also be essential in helping scientists to carefully monitor governments' efforts to meet their emission targets.