Operational use of ATOVS at the Met Office

The Met Office continues to make effective use of ATOVS radiances in Numerical Weather Prediction (NWP), and this use has been extended significantly in recent years. Whilst data from the HIRS instrument are used only in the global model, extensive use is now made of AMSU-A and AMSUB in regional and mesoscale NWP. Data is used from three satellites rather than two. In preparation for future developments research has been undertaken in a number of areas. This paper will focus on use of data over land, bias correction and the implementation of RTTOV version 7, as well as briefly discussing the impact of the third ATOVS instrument and preparations for SSMIS. Assimilation of ATOVS in regional and mesoscale NWP is discussed by Candy et al. (2003).