光学学报, 2012, 32 (8): 0828002, 网络出版: 2012-06-25
基于星载激光雷达数据的海面风速探测
Sea Surface Wind Speed Detection by Using the Data of CALIPSO Lidar
遥感 星载激光雷达 海面后向散射 海面风速 气溶胶光学厚度 remote sensing satellite-born lidar sea surface backscattering sea surface wind speed aerosol optical depth (AOD)
摘要
使用新版(Version 3.01)星载激光雷达CALIPSO Level 1剖面数据和Level 2的大气气溶胶光学厚度(AOD)数据反演全球海面风速。将AOD数据用于大气双程透射率的校正。对CALIPSO 所采集的2007年1月、4月、7月和10月532 nm 波长无云激光测量数据进行应用计算,采用532 nm退偏比经验修正海面白帽及水下次表层水体散射的影响,同时选用准同步的AMSR-E海面风速测量值为真值进行对比。对应2007年的4个月,由CALIPSO星载激光雷达532 nm单脉冲测量数据反演海面风速的标准偏差分别为1.24、1.24、1.24、1.20 m/s,由5 km滚动平均数据反演海面风速的标准偏差分别为0.98、1.02、0.98、0.94 m/s。结果表明,采用的数据反演方法可行且数据利用率得到提高。
Abstract
The global sea surface wind speeds are retrieved from the Version 3.01 CALIPSO lidar level 1 profile products and level 2 aerosol optical depth (AOD) products. The corresponding AOD data are used for correction of the two-way atmospheric transmittance, which allows wind speeds retrieval in the presence of significant amount of aerosols. Four months (January, April, July and October, 2007) of the CALIPSO lidar 532 nm data are selected. The AMSR-E sea surface wind speed data are collocated with the CALIPSO data and used for comparison. Effects from whitecaps and subsurface backscattering signals are corrected empirically using the lidar depolarization ratio measurement. The standard deviations of wind speeds retrieved by the CALIPSO lidar single-shot data and those by AMSR-E are 1.24, 1.24, 1.24, 1.20 m/s, respectively, for January, April, July and October, 2007. The standard deviations are reduced to 0.98, 1.02, 0.98, 0.94 m/s, respectively, when the lidar data is smoothed with a 5 km running window. The results show that the method works well and the data utilizing rate increases.
吴东, 张小雪, 阎逢旗, 刘兆岩. 基于星载激光雷达数据的海面风速探测[J]. 光学学报, 2012, 32(8): 0828002. Wu Dong, Zhang Xiaoxue, Yan Fengqi, Liu Zhaoyan. Sea Surface Wind Speed Detection by Using the Data of CALIPSO Lidar[J]. Acta Optica Sinica, 2012, 32(8): 0828002.