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Title: About the horizontal variability of effective radius in stratocumulus clouds: HORIZONTAL VARIABILITY OF R E IN STRATOCUMULUS CLOUDS

 [1];  [1];  [1]
  1. Department of Atmospheric Sciences, The Hebrew University of Jerusalem, Jerusalem Israel
Publication Date:
Sponsoring Org.:
OSTI Identifier:
Grant/Contract Number:
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Journal of Geophysical Research: Atmospheres
Additional Journal Information:
Journal Volume: 121; Journal Issue: 16; Related Information: CHORUS Timestamp: 2017-10-23 17:23:08; Journal ID: ISSN 2169-897X
Wiley Blackwell (John Wiley & Sons)
Country of Publication:
United States

Citation Formats

Magaritz-Ronen, L., Khain, A., and Pinsky, M.. About the horizontal variability of effective radius in stratocumulus clouds: HORIZONTAL VARIABILITY OF R E IN STRATOCUMULUS CLOUDS. United States: N. p., 2016. Web. doi:10.1002/2016JD024977.
Magaritz-Ronen, L., Khain, A., & Pinsky, M.. About the horizontal variability of effective radius in stratocumulus clouds: HORIZONTAL VARIABILITY OF R E IN STRATOCUMULUS CLOUDS. United States. doi:10.1002/2016JD024977.
Magaritz-Ronen, L., Khain, A., and Pinsky, M.. 2016. "About the horizontal variability of effective radius in stratocumulus clouds: HORIZONTAL VARIABILITY OF R E IN STRATOCUMULUS CLOUDS". United States. doi:10.1002/2016JD024977.
title = {About the horizontal variability of effective radius in stratocumulus clouds: HORIZONTAL VARIABILITY OF R E IN STRATOCUMULUS CLOUDS},
author = {Magaritz-Ronen, L. and Khain, A. and Pinsky, M.},
abstractNote = {},
doi = {10.1002/2016JD024977},
journal = {Journal of Geophysical Research: Atmospheres},
number = 16,
volume = 121,
place = {United States},
year = 2016,
month = 8

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1002/2016JD024977

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  • The equation of radiative energy balance in a homogeneous plane-parallel cloud accounts for the photon transport in the vertical direction only. From this equation, the absorption can be evaluated as a difference between the net radiative fluxes measured on the cloud top and bottom. Real clouds exhibit extreme horizontal variability of their optical and, hence, radiative properties. So the radiative energy balance equation for inhomogeneous clouds includes an extra term to describe the net energy transport in the horizontal directions (radiative horizontal transport). This study investigates the horizontal transport in nonhomogeneous stratocumulus clouds and its influence on the accuracy ofmore » absorption estimates. Using a realistic fractal model of marine stratocumulus clouds and Monte Carlo method, it is shown that the magnitude of horizontal transport (1) is comparable with those of albedo, transmittance, and absorptance and (2) depends strongly on the fractal dimension of cloud optical depth. Because of the horizontal transport, there is no unique dependence between optical and radiative properties of given pixel. The neglect of the horizontal transport is a major source of uncertainty in absorption estimates. Two possible ways of improving the inhomogeneous cloud absorption estimates from field measurements are discussed.« less
  • The spectral dependence of the radiative horizontal transport (the horizontal transport of radiative energy) E and its effect on the accuracy of spectral and broadband absorption retrieval in the near-infrared (IR) wavelength range was investigated using a large-eddy simulation (LES) cloud model with explicit microphysics and a three-dimensional Monte Carlo radiative transfer model. Two typical types of marine clouds representing inhomogeneous overcast and broken stratocumulus clouds have been simulated. We demonstrate that (i) the basic statistics (e.g., variance and correlation function) of the horizontal transport are wavelength dependent and (ii) the estimates of spectral and broadband absorption with a givenmore » accuracy (e.g., rmse ~4%) may require the use of different spatial resolutions.« less
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