Evaluation of wind vectors observed by HY-2A scatterometer using ocean buoy observations,ASCAT measurements,and numerical model data  

作　　者：李大伟 申辉 

机构地区：[1]Institute of Oceanology,Chinese Academy of Sciences [2]University of Chinese Academy of Sciences

出　　处：《Chinese Journal of Oceanology and Limnology》2015年第5期1191-1200,共10页中国海洋湖沼学报（英文版）

基　　金：Supported by the National High Technology Research and Development Program of China(863 Program)(No.2013AA09A505);the National Natural Science Foundation of China(No.40906091);the Open Project of School of Marine Sciences,Nanjing University of Information Science and Technology(No.KHYS1304)

摘　　要：The first Chinese microwave ocean environment satellite HY-2A was launched successfully in August, 201 I. This study presents a quality assessment of HY-2A scatterometer （HYSCAT） data based on comparison with ocean buoy data, the Advanced Scatterometer （ASCAT） data, and numerical model data from the National Centers for Environmental Prediction （NCEP）. The in-situ observations include those from buoy arrays operated by the National Data Buoy Center （NDBC） and Tropical Atmosphere Ocean （TAO） project. Only buoys located offshore and in deep water were analyzed. The temporal and spatial collocation windows between HYSCAT data and buoy observations were 30 min and 25 km, respectively. The comparisons showed that the wind speeds and directions observed by HYSCAT agree well with the buoy data. The root-mean-squared errors （RMSEs） of wind speed and direction for the HYSCAT standard wind products are 1.90 m/s and 22.80°, respectively. For the HYSCAT-ASCAT comparison, the temporal and spatial differences were limited to 1 h and 25 km, respectively. This comparison yielded RMSEs of 1.68 m/s for wind speed and 19.1° for wind direction. We also compared HYSCAT winds with reanalysis data from NCEP. The results show that the RMSEs of wind speed and direction are 2.6 m/s and 26°, respectively. The global distribution of wind speed residuals （HYSCAT-NCEP） is also presented here for evaluation of the HYSCAT-retrieved wind field globally. Considering the large temporal and spatial differences of the collocated data, it is concluded that the HYSCAT-retrieved wind speed and direction met the mission requirements, which were 2 rn/s and 20° for wind speeds in the range 2-24 m/s. These encouraging assessment results show that the wind data obtained from HYSCAT will be useful for the scientific community.The first Chinese microwave ocean environment satellite HY-2A was launched successfully in August,2011. This study presents a quality assessment of HY-2A scatterometer(HYSCAT) data based on comparison with ocean buoy data,the Advanced Scatterometer(ASCAT) data,and numerical model data from the National Centers for Environmental Prediction(NCEP). The in-situ observations include those from buoy arrays operated by the National Data Buoy Center(NDBC) and Tropical Atmosphere Ocean(TAO) project. Only buoys located offshore and in deep water were analyzed. The temporal and spatial collocation windows between HYSCAT data and buoy observations were 30 min and 25 km,respectively. The comparisons showed that the wind speeds and directions observed by HYSCAT agree well with the buoy data. The root-mean-squared errors(RMSEs) of wind speed and direction for the HYSCAT standard wind products are 1.90 m/s and 22.80°,respectively. For the HYSCAT-ASCAT comparison,the temporal and spatial differences were limited to 1 h and 25 km,respectively. This comparison yielded RMSEs of 1.68 m/s for wind speed and 19.1° for wind direction. We also compared HYSCAT winds with reanalysis data from NCEP. The results show that the RMSEs of wind speed and direction are 2.6 m/s and 26°,respectively. The global distribution of wind speed residuals(HYSCAT-NCEP) is also presented here for evaluation of the HYSCAT-retrieved wind field globally. Considering the large temporal and spatial differences of the collocated data,it is concluded that the HYSCAT-retrieved wind speed and direction met the mission requirements,which were 2 m/s and 20° for wind speeds in the range 2–24 m/s. These encouraging assessment results show that the wind data obtained from HYSCAT will be useful for the scientific community.

关 键 词：HY-2A SCATTEROMETER wind fields EVALUATION 

分 类 号：P715.2[天文地球—海洋科学] V447.1[航空宇航科学与技术—飞行器设计]