风云三号微波成像仪定标精度评价及业务产品介绍
Environmental Data Records from FengYun-3B Microwave Radiation Imager
中文摘要：
风云三号卫星（FY-3）为极轨系列卫星，目前为止分别于2008年5月和2010年10月发射了上午轨道（A）和下午轨道（B）两颗卫星。微波成像仪（MicroWave Radiometer Imager，MWRI）是装载于FY-3上的重要遥感仪器。该仪器为10通道双极化微波成像仪器，中心观测频率设置为10.65，18.7，23.8，36.5和89.0GHz，每个频点有垂直（V）和水平（H）两个探测通道。获取的对地观测亮温数据可用于定量获取大气降水、水汽、海面风速、海温、海冰分布、土壤湿度和陆表温度等地球物理参数信息。目前微波成像仪运行状态稳定，每天获取两次全球覆盖数据。主要介绍微波成像仪定标状况和主要业务产品算法。
中文关键词：
风云三号卫星，微波成像仪，定标
KeyWords：
FengYun (FY)-3, Microwave Radiation Imager (MWRI), calibration
Abstract：
Microwave Radiation Imagers (MWRIs) onboard the FengYun (FY)-3A/B satellites of China Meteorological Administration were launched on May 28, 2008, and November 5, 2010, respectively. They both observe the Earth atmosphere and land surface at 10.65, 18.7, 23.8, 36.5, and 89.0 GHz with dual polarization. After extensive on-orbit calibrations, the MWRI Level-1 data were collocated in space and time with the data from Aqua Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E), F18 Special Sensor Microwave Imager Sounder (SSMIS), and Tropical Rainfall Measuring Mission Microwave Imager for cross-calibration. A forward radiative transfer model was used to simulate the clear sky brightness temperatures at the MWRI frequencies over ocean. The differences between MWRI observations and model simulations, referred to as “O-A,” and the double difference results from pairs of MWRI and AMSR-E were examined. Comparing to the biases between AMSR-E/SSMIS measurements and model simulations, the biases for MWRI are small and stable. Atmospheric and surface geophysical parameters are retrieved from MWRI observations using the heritage algorithms. It is shown that these environmental data records from MWRI are comparable with those similar data products from AMSR-E and SSMIS. Their biases from each other seemed to be minimal.