Analysis of the Observation Results for Preferentially Oriented Particles in High-Level Clouds According to the EARLINET Lidar Network and MODIS Data

Abstract

This analysis presents the results of observation episodes for high-level clouds consisting of ice crystals with different orientations in space, using the EARLINET lidar network and MODIS data over Europe from 2015 to 2022. The technique used involves identifying specular reflecting layers through ground-based laser soundings of the atmosphere and finding synchronous images from space, followed by the retrieval of cirrus cloud parameters. The study considers several properties of high-level clouds, including reflection ratio (ρ), effective emissivity (ε), optical thickness, effective particle radius, water path, and top height, according to MODIS data. The results of retrieving these properties for cirrus clouds with different orientations of ice crystals over individual EARLINET lidar stations and over Europe as a whole are discussed. The study indicates that high-level clouds with ρ ≥ 0.15 and ε ≥ 0.4 definitely contain specular reflecting layers.