Satellite sounding of the atmosphere  Better assimilation of
passive microwave and infrared satellite data to improve the
analysis of temperature, moisture and surface fields within the
Met Office NWP Model.  This area of research focuses on
improving the way we use passive satellite data from microwave
and infrared sensors to improve our forecasting capabilities,
primarily via the assimilation of these data into our NWP
(Numerical Weather Prediction) models.  Passive remote sensing
uses the natural radiation signature emitted by the atmosphere
or surface. It uses the fact that the radiation reaching the
satellite will vary from wavelength to wavelength depending upon
the temperature structure of the intervening atmosphere and the
presence of any absorbing gases and clouds. The method contrasts
with active satellite sensing techniques, where an instrument
measures artificially-generated radiation emitted by a
satellite, and received by either the same instrument or another
receiver.  Microwave sounding is cru