Presenting Author: Dr. Hans Hersbach
At the European Centre for Medium-Range Weather Forecasts (ECMWF) scatterometer winds have been assimilated in the operational integrated forecast and assimilation system from 30 January 1996 onwards. The four-dimensional variational assimilation system at ECMWF allows for a dynamically consistent use of observations. In this way, information of scatterometer surface winds is propagated to the entire troposphere. Currently, data is used from the AMI scatterometer on-board the European Remote sensing Satellites ERS-2 (from June 1996 onwards), the SeaWinds instrument on-board QuikSCAT (from January 2002 onwards), and from the ASCAT instrument on the MetOp-A platform (from June 2007 onwards). Thanks to the different timing of ascending nodes of these three satellites, most areas on the globe are covered within a six-hour period. Morning and afternoon are captured by QuikSCAT, while noon and midnight are served by ASCAT and ERS-2. Besides active assimilation, the characteristics of scatterometer data are routinely monitored and inter compared. An example of cross validation will be given. A recent change in the usage of QuikSCAT data, and the recent construction of a C-band geophysical model function for equivalent neutral wind (called CMOD5.N), will be presented. Some preliminary results of ongoing research regarding the inclusion of the effects of ocean currents and atmospheric stability on the assimilation of scatterometer data will be discussed.
2019 International OVWST Meeting
May 29-31 in Portland, Maine, USA