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NASA NTRS · 20150018351

Testing the Two-Layer Model for Correcting Clear Sky Reflectance near Clouds

Wen, Guoyong·Marshak, Alexander·Evans, Frank·Varnai, Tamas·Levy, Rob
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Abstract

A two-layer model (2LM) was developed in our earlier studies to estimate the clear sky reflectance enhancement due to cloud-molecular radiative interaction at MODIS at 0.47 micrometers. Recently, we extended the model to include cloud-surface and cloud-aerosol radiative interactions. We use the LES/SHDOM simulated 3D true radiation fields to test the 2LM for reflectance enhancement at 0.47 micrometers. We find: The simple model captures the viewing angle dependence of the reflectance enhancement near cloud, suggesting the physics of this model is correct; the cloud-molecular interaction alone accounts for 70 percent of the enhancement; the cloud-surface interaction accounts for 16 percent of the enhancement; the cloud-aerosol interaction accounts for an additional 13 percent of the enhancement. We conclude that the 2LM is simple to apply and unbiased.

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Wen, Guoyong, Marshak, Alexander, Evans, Frank, Varnai, Tamas, Levy, Rob. 2015-05-18. Testing the Two-Layer Model for Correcting Clear Sky Reflectance near Clouds. https://ntrs.nasa.gov/citations/20150018351

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