利用组合式拉曼弹性后向散射激光雷达对卷云中消光和后向散射廓线进行独立测量。

Independent measurement of extinction and backscatter profiles in cirrus clouds by using a combined Raman elastic-backscatter lidar.

作者信息

Ansmann A, Wandinger U, Riebesell M, Weitkamp C, Michaelis W

出版信息

Appl Opt. 1992 Nov 20;31(33):7113. doi: 10.1364/AO.31.007113.

DOI:10.1364/AO.31.007113

PMID:20802574

Abstract

Height profiles of the extinction and the backscatter coefficients in cirrus clouds are determined independently from elastic- and inelastic- (Raman) backscatter signals. An extended error analysis is given. Examples covering the measured range of extinction-to-backscatter ratios (lidar ratios) in ice clouds are presented. Lidar ratios between 5 and 15 sr are usually found. A strong variation between 2 and 20 sr can be observed within one cloud profile. Particle extinction coefficients determined from inelastic-backscatter signals and from elastic-backscatter signals by using the Klett method are compared. The Klett solution of the extinction profile can be highly erroneous if the lidar ratio varies along the measuring range. On the other hand, simple backscatter lidars can provide reliable information about the cloud optical depth and the mean cloud lidar ratio.

摘要

卷云中消光系数和后向散射系数的高度分布是根据弹性后向散射信号和非弹性（拉曼）后向散射信号独立确定的。给出了扩展的误差分析。给出了涵盖冰云中消光与后向散射比（激光雷达比）测量范围的示例。通常发现激光雷达比在5至15 sr之间。在一个云剖面内可以观察到2至20 sr之间的强烈变化。比较了通过使用克莱特方法从非弹性后向散射信号和弹性后向散射信号确定的粒子消光系数。如果激光雷达比沿测量范围变化，消光剖面的克莱特解可能会有很大误差。另一方面，简单的后向散射激光雷达可以提供有关云光学厚度和平均云激光雷达比的可靠信息。