IASI radiance simulations in preparation for near real-time data distribution

A simulation system is under development to support pre-launch preparations for the Infrared Atmospheric Sounding Interferometer (IASI) near real-time processing and distribution system and for cloud clearing algorithm development. IASI, a Fourier Transform spectrometer with over 8450 channels per spectrum, will fly on the METOP satellite series that is dedicated to the operational meteorology and climate monitoring. The METOP-1, due to be launched in late 2005, will have a sun-synchronous orbit with a 9.30 equator local crossing time. The IASI simulation system will emulate the instrumental and orbital characteristics of the IASI instrument on METOP-1 and produce 1.3 million spectra/day. The utility of this system is (1) to provide simulated observation radiances that support cloud clearing algorithm development and testing, (2) to provide a robust data distribution environment for development and testing of the IASI data sub-setting system, and (3) most importantly, to allow for a smooth transition of the IASI data processing system from the development environment to the operational environment, during both the integration and test phases of the transition. Details of the simulation system shall be presented.