The assimilation of Infrared Atmospheric Sounding Interferometer radiances at ECMWF

Abstract

Abstract The assimilation of Infrared Atmospheric Sounding Interferometer (IASI) radiances at the European Centre for Medium‐Range Weather Forecasts (ECMWF) is described. The configuration of the IASI radiance assimilation system relies heavily on the experience obtained from using Atmospheric InfraRed Sounder (AIRS) data over the previous five years. IASI observations are found to be of high quality, particularly in the important region of the 15 µm temperature‐sounding band. The choice of channels to be actively assimilated is focused on this 15 µm band and experiments have shown that the additional use of IASI data produces a statistically significant positive impact on forecast quality. Copyright © 2009 Royal Meteorological Society