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GCOS Atmospheric Surface ECV: Wind Speed & Direction Ocean Surface Winds Satellite Observations: Polar-orbiting satellites provide information on surface wind with global coverage, good horizontal resolution and acceptable accuracy, though temporal frequency is marginal for regional mesoscale forecasts. They provide useful information in two ways: scatterometers provide dense observations of wind direction and speed along a narrow swath, although the most recent and planned scatterometers provide better coverage via broader swaths (90% global coverage daily); scatterometers have made a positive impact in predicting marine forecasting, operational global NWP and climate forecasting; passive microwave imagers and altimeters provide information on wind speed only. The single swath scatterometer on ERS-1/2 and the broad swath scatterometer on QuikSCAT have long provided adequate coverage. QuikSCAT, launched in 1999, carries the SeaWinds scatterometer that measures near-surface wind speed and direction in all weather and cloud conditions. Global coverage by a broad swath scatterometer is now provided by ASCAT on the European MetOp-A mission. Developed by ESA as a follow-on from the ‘wind mode’ of the AMI on the ERS series, ASCAT is used primarily for global measurement of sea surface wind vectors and provides quasi-global coverage within 24 hours. The SSM/I (Special Sensor Microwave/ Imager) on board the US DMSP satellites is currently providing operational surface wind data. The cooperative NASA/JAXA AMSR-E on Aqua (launched in 2002) also provides data on sea surface wind speed. Future Satellite Observations: Starting with the second satellite, C-2, the operational NPOESS missions will use the CMIS instrument, which employs a passive microwave approach for collecting data on sea surface winds.In recent years, the ability to detect and track severe storms has been dramatically enhanced by the advent of weather satellites. Data from SeaWinds is augmenting traditional satellite images of clouds by providing direct measurements of surface winds enabling better determination of a storm’s location, direction, structure and strength. In its response to the GCOS IP, CEOS agreed to review the capability of passive microwave sensors to make scatterometer-quality measurements and will work to ensure AM and PM satellite coverage of surface wind speed and direction by 2015.(Source: CEOS) Satellite Missions, present and future [ECV Matrix Main Page] [About the ECV Matrix] [Reference Documents] [Contact] |
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