Strategic Study of CAE >> 2013, Volume 15, Issue 7
HY-2A microwave scatterometer wind retrieval algorithm
National Satellite Ocean Application Sevice, Beijing 100081, China
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Abstract
The routine wind fields retrieval algorithm for China's microwave scatterometer onboard HY-2A (HY2-SCAT) was developed. By introducing a two-step search schema into the wind retrieval process, which included a coarse-search and an optimal-search, the efficiency of wind retrieval was greatly improved. Circular median filter was applied to remove the ambiguities, and the NCEP wind field was used as a background to re-initialized wind field consists of ambiguous wind vectors, so that the ambiguity removal skill can be largely enhanced. Wind vectors observed by HY2-SCAT were evaluated by comparison with NDBC buoy observations and ASCAT observations. The RMS difference was less than 2 m/s or less than 10 % for the comparison of wind speeds and the RMS difference was less than 20 degree for the comparison of wind direction, which indicated that the wind products provided by HY2-SCAT can meet the requirements for science and routine meteo users.
Keywords
HY-2A ; microwave scatterometer ; wind fields retrieval algorithm
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