Retrieval of Greenhouse and Related Gas Parameters from SCIAMACHY/ENVISAT

The Kyoto Protocol, recently ratified by the EU, calls for a reduction in the emission of greenhouse gases in the period 2008 to 2012. However, global greenhouse gas emissions and absorptions, sources and sinks, are not well known. There is a large discrepancy between bottom-up emission estimates, derived from national government energy, transport, agricultural, etc. figures, and top-down estimates derived from atmosphere concentration distributions. Many parts of the world are poorly monitored (southern hemisphere, oceans) and some countries do not take part in the treaty. Measurements from ENVISAT, the ESA earth observation satellite presently in operation, are expected to improve this situation. The SCIAMACHY instrument on ENVISAT is able to probe the troposphere where the emission and absorption of greenhouse gases takes place. space measurements, modelling and ground-based data will yield the required level of accuracy. The gases to be investigated are CO₂, CH₄, N₂O, O₃, H₂O, CO and NO₂. The focus will be on methane and carbon monoxide because of their importance for the Kyoto Protocol and their relatively good feasibility prospect. This TROPOSAT work forms part of a wider European collaboration, the EVERGREEN project of the European Commission 5th Framework Programme on Environment and Sustainable Development, to be carried out in the period 2003 to 2006.