Open AccessA Simple Model for Stratocumulus to Shallow Cumulus Cloud Transitions
Author(s) -
Daniel Chung,
J. Teixeira
Publication year - 2012
Publication title -
journal of climate
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.315
H-Index - 287
eISSN - 1520-0442
pISSN - 0894-8755
DOI - 10.1175/jcli-d-11-00105.1
Subject(s) - longwave , marine stratocumulus , cloud fraction , climatology , latent heat , atmospheric sciences , flux (metallurgy) , environmental science , sea surface temperature , radiative transfer , radiative flux , radiative cooling , meteorology , cloud cover , cloud computing , geology , physics , materials science , aerosol , quantum mechanics , computer science , metallurgy , operating system
It is shown that essential features of stratocumulus to shallow cumulus cloud transitions can be represented by a simple stochastic model constructed from an ensemble of transitions, each of which depends on the amount of surface latent heat flux relative to initial cloud-top longwave net radiative flux. In its essence the simple model establishes a causal relation between the increase of sea surface temperature (SST) and the decrease in cloud fraction (CF) along the trade winds. The mean and variance of SST are taken from observations. Model predictions are compared with observations of CF along Lagrangian trajectories in four eastern subtropical ocean regions. The model reproduces well the decrease in mean CF and the peak in CF spread.