卫星散射计与海面平台所测的风场数据比较

Comparison of seawind data between spaceborne scatterometer and platform measurements

基于南海北部海面PY30-1石油平台气象站测风仪2011年7月19日—2012年9月17日实测的风场数据,分别开展了对卫星搭载的ASCAT和HY-2散射计所测风场数据的比较研究,分析散射计的测风能力(选取的时空窗口为30min和25km)。结果表明:在南海北部海域,ASCAT散射计所测风速和PY30-1石油平台气象站观测风速的均方根误差为2.53m/s,风向偏差较大,均方根误差为47.87°;HY-2散射计所测风速和PY30-1石油平台气象站观测风速的均方根误差为3.41m/s,风向的均方根误差为58.66°。分别按低、中和高风速的不同条件将ASCAT和HY-2散射计所测的风场数据与PY30-1石油平台气象站观测的风场数据加以比较可知,ASCAT和HY-2散射计都具有较好的测风能力,前者所测风速与PY30-1石油平台气象站测风仪观测风速的均方根误差稍小于后者。在150min和15km的时空窗口下,ASCAT与HY-2散射计所测风速的均方根误差为0.72m/s,风向的均方根误差为8.50°。

The wind data from ASCAT were compared with those of HY-2 satellite,and their accuracy were verified with the data from oil platform in the northern South China Sea,which were collected from Jul.19,2011 to Sept.17,2012.The RMS（root-mean-square error） between ASCAT wind speed data and the platform-measured wind speed data is about 2.53 m/s.The RMS between ASCAT wind direction data and the platform-measured wind direction data is about 47.87°.The RMS between HY-2 wind speed data and the platform-measured wind speed data is about 3.41 m/s.The RMS between HY-2 wind direction data and the platform-measured wind direction data is about 58.66°（The temporal and spatial differences between the ASCAT and HY-2 date were limited to less that 30 min and 25 km）.With the temporal and spatial differences between ASCAT and HY-2 date were limited to less than 150 min and 15 km,the RMS between ASCAT wind speed data and HY-2 wind speed data were also calculated in this paper,which were about 0.72 m/s.The RMS between ASCAT wind direction data and HY-2 wind direction data were about 8.50°.In conclusion,the measured data of ASCAT were a little better than those of HY-2,and it provide a basis for using seawind data of satellite in the northern South China Sea.