An application of the tilted independent pixel approximation to cumulonimbus environments

Jeffrey Frame, Jonathan L. Petters, Paul M. Markowski, Jerry Y. Harrington

Research output: Contribution to journalArticle

Abstract

Most radiative transfer parameterizations in numerical cloud models transfer radiation in the vertical direction only, utilizing the independent pixel approximation. This method cannot correctly simulate neither the location nor the shape of cloud shadows because shortwave radiation only propagates vertically, and thus it does not account for the slanted path the direct solar beam takes through the atmosphere. Herein, the tilted independent pixel approximation, which more properly accounts for the geometry of the direct solar beam, is applied to a cumulonimbus cloud field. This computationally inexpensive method results in a more accurately modeled cloud shadow at the surface, allowing for more accurate computations of near-surface air temperatures.

Original languageEnglish (US)
Pages (from-to)127-136
Number of pages10
JournalAtmospheric Research
Volume91
Issue number1
DOIs
StatePublished - Jan 1 2009
Externally publishedYes

Fingerprint

cumulonimbus
pixel
shortwave radiation
radiative transfer
parameterization
surface temperature
air temperature
geometry
atmosphere
method

Keywords

  • Clouds
  • Numerical modeling
  • Radiation
  • Radiative transfer
  • Thunderstorms

ASJC Scopus subject areas

  • Atmospheric Science

Cite this

An application of the tilted independent pixel approximation to cumulonimbus environments. / Frame, Jeffrey; Petters, Jonathan L.; Markowski, Paul M.; Harrington, Jerry Y.

In: Atmospheric Research, Vol. 91, No. 1, 01.01.2009, p. 127-136.

Research output: Contribution to journalArticle

Frame, Jeffrey ; Petters, Jonathan L. ; Markowski, Paul M. ; Harrington, Jerry Y. / An application of the tilted independent pixel approximation to cumulonimbus environments. In: Atmospheric Research. 2009 ; Vol. 91, No. 1. pp. 127-136.
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