基于CALIPSO卫星数据的全球大气边界层高度时空分布特征

Study on temporal and spatial distribution of global PBL height based on CALIPSO satellite data

通过CALIPSO卫星观测数据利用改进的最大标准差方法反演了全球范围2009年1月-2014年12月的行星边界层(PBL)高度.针对CALIPSO卫星获得的PBL高度,利用SACOL站NIES激光雷达和ECMWF PBL高度数据进行了验证.结果表明,CALIPSO卫星数据与NIES激光雷达数据的相关性为0.83,ECMWF与NIES激光雷达数据的相关性为0.41,均通过95%的显著性水平检验.全球陆地PBL高度以及季节变化趋势都明显高于海洋,且呈现相反的变化趋势,陆地PBL高度最大值发生在夏季,最小值出现在冬季,而水面上则相反;中国区域PBL高度常年存在两个高值中心,分别位于青藏高原和沿海地区;冬季北美和亚洲东部海岸沿线地区的PBL高度比周围海洋PBL高度明显偏高;CALIPSO卫星获得的全球平均PBL高度75%集中在距地面2km以内的范围,集中在0.5~0.75 km的最多.

Using maxing standard deviation method,this paper inversed global planetary boundary layer(PBL)height based on CALIPSO observation data from January 2009 to December 2014.The inversion results were validated using NIES lidar from the SACOL site and ECMWF PBL height data.The results showed that the correlation coefficient between CALIPSO PBL height and NIES PBL height was 0.83 and the correlation coefficient between ECMWF PBL height and NIES PBL height was 0.41,which both passed the significant test at the 0.95 level.Global PBL height over land and its seasonal variation trend were greater than those over water,and seasonal variation trend of global PBL height over land was opposite to that over water,i.e.global PBL height over land was maximal in summer and minimal in winter,while that over water was just the opposite.There were two distinct high value centers of PBL height over China throughout the year and they were located in Qinghai-Tibet Plateau and coastal areas.PBL heights over the east coasts of North America and Asia in winter were greater than those over neighboring waters.The results also showed that 75%of the global PBL height from CALIPSO were less than 2 km and the data were mostly distributed from 0.5 to 0.75 km.