风云三号卫星微波温度计的在轨性能长期稳定性分析  

Long-Term Calibration and Accuracy Assessment of the FengYun-3 Microwave Temperature Sounder Radiance Measurements

作　　者：游然[1] 谷松岩[1] 郭阳[1] 吴学宝[1] 杨虎[1] 陈文新 

机构地区：[1]国家卫星气象中心,中国气象局,北京100081 [2]中国航天科技集团公司,北京100048

出　　处：《气象科技进展》2013年第4期13-17,共5页Advances in Meteorological Science and Technology

基　　金：国家重点基础研究发展计划(973计划)项目2010CB951600);国家自然科学基金资助项目(40605008);国家高新技术研究发展计划863计划)项目(2007AA12Z115);科技部国际科技合作专项(2010DFA21140)

摘　　要：中国风云三号(FY-3)A星于2008年5月27日成功发射,其上装载的微波温度计(Microwave Temperature Sounder,MWTS)有4个通道,频率分别为50.3,53.596,54.94和57.29GHz,可提供地面至平流层下部的大气温度廓线信息。介绍了MWTS的仪器特征和定标方法,对FY-3A发射后MWTS的仪器性能相关参数的长序列特征进行了监测分析,这些参数主要包括灵敏度、冷空和内部暖黑体的计数值、仪器温度和通道增益。通过再分析资料和微波辐射传输模拟,比较了FY-3A卫星MWTS与NOAA-18卫星先进微波温度探测器(Advanced Microwave Sounder Unit-A,AMSU-A)的观测和模拟的亮温偏差。结果表明,MWTS所有通道的灵敏度值优于其指标;通道1和3的亮温偏差与AMSU-A接近;通道2和4的偏差比AMSU-A要大一些。The Chinese FengYun-3(FY-3)A satellite was successfully launched on May 27,2008,with a Microwave Temperature Sounder(MWTS) onboard.MWTS has four channels with frequencies of 50.3,53.596,54.94,and 57.29 GHz,respectively.The MWTS measurements are primarily used for profiling atmospheric temperatures from surface to lower stratosphere.MWTS is a cross-track scanning instrument,and its Earth-view measurements are calibrated through the warm target and cold space measurements during every scan cycle.In this paper,the FY-3A MWTS and its channel characteristics are first introduced.The calibration process and the postlaunch instrument performance are then presented,including the long-term trends of noise equivalent differential temperature(NEDT),calibration counts from cold space and warm targets,instrument telemetry,and channel gains.The observed and simulated brightness temperature(BT) differences of MWTS and Advanced Microwave Sounding Unit-A(AMSU-A) are compared.It is shown that the MWTS NEDT values at all channels are much better than its specification.The BT biases of MWTS channels 1 and 3 with respect to the simulations are similar in magnitude to those from National Oceanic and Atmospheric Administration-18 AMSU-A.The MWTS biases at channels 2 and 4 are larger than AMSU-A.

关 键 词：定标 风云三号(FY-3) 微波温度计(MWTS) 

分 类 号：P414.4[天文地球—大气科学及气象学]