Shaw Joseph A, Pust Nathan J
Electrical and Computer Engineering Department, Montana State University, Bozeman, Montana 59717, USA.
Appl Opt. 2011 Oct 1;50(28):F6-11. doi: 10.1364/AO.50.0000F6.
Dual-polarization lidar data and radiosonde data are used to determine that iridescence in cirrus and a lunar corona in a thin wave cloud were caused by tiny ice crystals, not droplets of liquid water. The size of the corona diffraction rings recorded in photographs is used to estimate the mean diameter of the diffracting particles to be 14.6 μm, much smaller than conventional ice crystals. The iridescent cloud was located at the tropopause [~11-13.6 km above mean sea level (ASL)] with temperature near -70 °C, while the more optically pure corona was located at approximately 9.5 km ASL with temperature nearing -60 °C. Lidar cross-polarization ratios of 0.5 and 0.4 confirm that ice formed both the iridescence and the corona, respectively.
利用双偏振激光雷达数据和无线电探空仪数据确定，卷云中的虹彩现象以及薄波状云中的月晕是由微小冰晶而非液态水滴造成的。照片中记录的晕衍射环大小用于估计衍射粒子的平均直径为14.6微米，远小于传统冰晶。虹彩云位于对流层顶[平均海平面（ASL）以上约11 - 13.6千米]，温度接近-70°C，而光学上更纯净的晕位于约9.5千米ASL处，温度接近-60°C。激光雷达交叉偏振比分别为0.5和0.4，证实冰分别形成了虹彩和晕。
