Improved assimilation of data from China's FY-3A Microwave Temperature Sounder (MWTS)

TitleImproved assimilation of data from China's FY-3A Microwave Temperature Sounder (MWTS)
Publication TypeMiscellaneous
Year of Publication2011
AuthorsLu, Q, Bell, W, Bauer, P, Bormann, N, Peubey, C, Geer, AJ
Secondary TitleTechnical Memorandum
Number642
Pagination13
Date PublishedFebruary
PublisherECMWF
Type of WorkTechnical Memorandum
Abstract

The FY-3A MWTS suffers from radiometer non-linearities and uncertainties in passband centre frequencies. Corrections have been developed, and are assessed here by comparing re-calibrated MWTS data with equivalent AMSU-A observations. The corrections are effective in improving the first guess departure statistics for MWTS, relative to the original un-corrected data, to values close to those for AMSU-A equivalent channels. In observing system experiments MWTS observations improve the first guess fits for AMSU-A observations. Forecast verification shows a systematic improvement by using the re-calibrated data, for example forecasts of 200 hPa geopotential are improved to Day 4 in the SH by approximately 1%.