Passive microwave
by Mary Forsythe — last modified Feb 08, 2012 08:48 AM
Contents
Derivation
Passive microwave instruments can provide information on the wind field in rain-free areas. Earlier instruments could only provide wind speed; WindSat, onboard the NRL research satellite Coriolis, is the first microwave radiometer capable of providing additional information on the direction, although with similar ambiguity to scatterometer instruments. This is possible because the orientation of the surface waves affects the way the emitted radiation is polarised and, unlike other microwave instruments, WindSat can measure the full polarisation state of the radiation.
For information on the WindSat processing software see WindSat - Remote Sensing of Ocean Surface Winds (NRL Review article)
Advice for research users
Real-time plots
Plots of WindSat winds are produced in real-time. These can be useful for forecasters and as a tool for better understanding the WindSat data.
Monitoring
- NWP SAF scatterometer and WindSat monitoring - real time and monthly monitoring information.
NWP usage and impact
For information on NWP usage see the NWP SAF AMV web pages at http://research.metoffice.gov.uk/research/interproj/nwpsaf/scatter_report/nwp.html
For information on NWP impact see the winds impact study under the IWWG activities section.
Other users
- WindSat winds can be used directly by forecasters and can be helpful in meteorologically interesting areas (e.g. tropical cyclones....) or in cases of increased NWP model uncertainty.