期刊名称:Journal of Advances in Modeling Earth Systems
电子版ISSN:1942-2466
出版年度:2013
卷号:5
期号:4
页码:1-12
DOI:10.1002/jame.20047
出版社:John Wiley & Sons, Ltd.
摘要:Tropical deep convection exhibits a variety of levels of aggregation over a wide range of scales. Based on a multisatellite analysis, the present study shows at mesoscale that different levels of aggregation are statistically associated with differing large‐scale atmospheric states, despite similar convective intensity and large‐scale forcings. The more aggregated the convection, the dryer and less cloudy the atmosphere, the stronger the outgoing longwave radiation, and the lower the planetary albedo. This suggests that mesoscale convective aggregation has the potential to affect couplings between moisture and convection and between convection, radiation, and large‐scale ascent. In so doing, aggregation may play a role in phenomena such as “hot spots” or the Madden‐Julian Oscillation. These findings support the need for the representation of mesoscale organization in cumulus parameterizations; most parameterizations used in current climate models lack any such representation. The ability of a cloud system‐resolving model to reproduce observed relationships suggests that such models may be useful to guide attempts at parameterizations of convective aggregation.
关键词:tropical deep convection;convective aggregation;satellite observations cloud‐system resolving model;cumulus parameterization;large‐scale circulation