Influence of a stochastic moist convective parameterization on tropical climate variability

• Published in: Geophysical research letters Vol. 27; no. 22; pp. 3691 - 3694
• Main Authors: Lin, Johnny Wei-Bing, Neelin, J. David
• Format: Journal Article
• Language: English
• Published: Washington, DC Blackwell Publishing Ltd 15.11.2000; American Geophysical Union
• Subjects: Earth, ocean, space; Exact sciences and technology; External geophysics; General circulation. Atmospheric waves; Meteorology; Parametrization; Atmospheric convection; Available potential energy; General circulation models; Tropical climate; Variability
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/2000GL011964

Convective parameterizations used in general circulation models (GCMs) generally only simulate the mean or first‐order moment of convective ensembles and do not explicitly include higher‐order moments. The influence of including unresolved higher‐order moments is investigated using a simple stochastic convective parameterization that includes a random contribution to the convective available potential energy (CAPE) in the deep convective scheme. Impacts are tested in an tropical atmospheric model of intermediate complexity. Adding convective noise noticeably affects tropical intraseasonal variability, suggesting inclusion of such noise in GCMs might be beneficial. Model response to the noise is sensitive not only to the noise amplitude, but also to such particulars of the stochastic parameterization as autocorrelation time.