摘要
卷云在大气辐射中扮演着重要角色,对天气系统和气候变化产生重要影响。相比传统地基观测手段,卫星遥感更容易探测到高层卷云的信息,本文利用CALIOP主动遥感仪器可获取较为准确的薄卷云特性的特点,针对MODIS被动遥感探测器反演的薄卷云云顶高度的偏差开展订正研究。研究选取2013~2017年京津冀地区MODIS云产品,结合CALIPSO卫星的卷云云顶高度数据,基于交叉验证的方法得到线性拟合方案,对MODIS卷云云顶高度进行订正。订正后的MODIS与CALIPSO卷云云顶高度差值的分布区间由-3~2 km变为-2.0~2.5 km,峰值由-0.8 km左右变为0.2 km左右。订正效果随云顶高度和云光学厚度的不同有所变化,其中较低层卷云和光学薄卷云的订正效果更明显。
Cirrus clouds play an important role in atmospheric radiation and affect weather systems and climate change.Satellite remote sensing has considerable advantage in cirrus cloud detection, relative to traditional observation. As a passive remote sensing instrument, large deviations in the thin cirrus cloud top height data from the Moderate Resolution Imaging Spectroradiometer(MODIS) are detected. Comparatively, the Cloud–Aerosol Lidar with Orthogonal Polarization(CALIOP) aboard the Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observation(CALIPSO), which is an active remote sensing instrument, can acquire more accurate characteristics of thin cirrus cloud. In this study, MODIS cloud products in the Beijing–Tianjin–Hebei region from 2013 to 2017 are selected. Using the CALIPSO cirrus cloud top height data, a linear fitting method based on the cross-validation method is obtained, and the MODIS cirrus cloud top height data are corrected. The difference between MODIS and CALIPSO changes from -3 to 2 km to -2.0 to 2.5 km. Moreover, the maximum difference changes from approximately-0.8 km to approximately 0.2 km. In the context of different vertical levels and cloud optical depths, MODIS cirrus cloud top height data are improved after correction, which is more obvious at the lower cloud top height and optically thinner cirrus clouds.
作者
杨冰韵
刘健
贾煦
YANG Bingyun;LIU Jian;JIA Xu(National Satellite Meteorological Center,Beijing 100081)
出处
《大气科学》
CSCD
北大核心
2020年第5期1013-1022,共10页
Chinese Journal of Atmospheric Sciences
基金
国家自然科学基金项目61531019
国家重点研发计划专项项目2018YFC1407204、2018YFC1506603。
