THE ATMOSPHERIC DYNAMICS MISSION

The primary aim of the Earth Explorer Atmospheric Dynamics Mission is to provide improved analyses of the global three-dimensional wind field by demonstrating the capability to correct the major deficiency in wind-profiling of the current GOS and GCOS. The ADM will provide the windprofile measurements to establish advancements in atmospheric modelling and analysis. There is an intimate link between progress in climate modelling and progress in numerical weather prediction (NWP) as our understanding of the atmosphere is largely based on the experience of operational weather centres. Long-term data bases are being created by NWP data assimilation systems to serve the climate research community. It is widely recognised therefore that the impact of a new global atmospheric observing system on our understanding of atmospheric dynamics should be evaluated primarily in the context of operational weather forecasting. New insights into the atmosphere through the provision of wind profiles are expected for NWP but also for climate research. The ADM is addressing one of the main areas discussed under Theme 2 of the ‘ESA Living Planet Programme’ (ESA, 1998). Although there are several ways of measuring wind from a satellite, only the active Doppler Wind Lidars (DWL) has the potential to provide the requisite data globally. It is the only candidate so far that can provide direct observations of wind profiles. In addition, a DWL will not only provide wind data but also has the potential to provide ancillary information on cloud top heights, vertical distribution of cloud, aerosol properties, and wind variability as by-products.