用红外和水汽两个通道的卫星测值指定云迹风的高度

HEIGHT ASSIGNMENT OF CLOUD MOTION WINDS WITH INFRARED AND WATER VAPOUR CHANNELS

中文关键词:  云迹风  云分析  云高指定

英文关键词:Cloud motion wind  Cloud analysis  Height assignment of cloud

中文摘要:

      提出了一种改进的用红外和水汽两个通道的测值指定云迹风高度的算法.利用红外水汽散点图和云迹风本身自动地将有低云的目标区、有半透明卷云的目标区、有密蔽高云的目标区分开.在有低云的目标区和有密蔽高云的目标区用红外一个通道指定云高.在有半透明卷云的目标区用红外和水汽两个通道指定云高.在用两个通道的测值指定云高时,假定卷云高度以上不存在水汽,以红外和水汽两个通道亮温相同这个方程与两个通道辐射测值线性相关的方程联立解出云的高度.

英文摘要:

      An improved cloud motion wind height assignment algorithm with infrared window channel and water vapour absorption channel was proposed.Our algorithm separates tracers with cirrus clouds from the ones with lower level clouds.For tracers with cirrus clouds,both infrared and water vapour channels were used in height assignment;while for tracers with lower level clouds,only infrared channel was used.In case of cirrus cloud tracers,it is assumed that there is no any water vapour above cirrus cloud level.With this assumption,the original clouds should be observed by the satellite with same brightness temperature at both infrared and water vapour channels.Combine the above relationship with the statistic relationship between infrared and water vapour measurements,height assignment of semi-transmissive cirrus cloud was made.