Thermodynamic phase retrieval of convective clouds: impact of sensor viewing geometry and vertical distribution of cloud properties
Author:
Jäkel E.,Walter J.,Wendisch M.
Abstract
Abstract. The potential to use combined passive and active remote sensing measurements to retrieve microphysical parameters of convective clouds in particular thermodynamic phase, is investigated by three-dimensional (3-D) radiative transfer simulations. The 3-D simulations are used to quantify the effect of different viewing geometries and distributions of the cloud microphysical properties on the derived ice index. Measurement examples of spectral solar and radiance reflected by cloud sides (passive) in the near-infrared (NIR) spectral range are synchronized with collocated Lidar observations (active). A retrieval method to distinguish the cloud thermodynamic phase (liquid water or ice) using the reported reflectivity measurements is applied which uses the different spectral slopes of water and ice clouds in the NIR. The concurrent depolarization backscattering Lidar provides geometry information about the cloud distance and height as well as the depolarization.
Publisher
Copernicus GmbH
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