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Title: Seasonal Dependency of Tropical Precipitation Change under Global Warming
Abstract Tropical precipitation change under global warming varies with season. The present study investigates the characteristics and cause of the seasonality in rainfall change. Diagnostically, tropical precipitation change is decomposed into thermodynamic and dynamic components. The thermodynamic component represents the wet-get-wetter effect and its seasonality is due mostly to that in the mean vertical velocity, especially in the monsoon regions. The dynamic component includes the warmer-get-wetter effect due to the spatial variations in sea surface temperature (SST) warming, while the seasonality is due to that of the climatological SST and can be largely reproduced by an atmospheric model forced with the monthly climatological SST plus the annual-mean SST warming pattern. In the eastern equatorial Pacific where the SST warming is locally enhanced; for example, rainfall increases only during the March–May season when the climatological SST is high enough for deep convection. To the extent that the seasonality of tropical precipitation change over oceans arises mostly from that of the climatological SST, the results support the notion that reducing model biases in climatology improves regional rainfall projections.  more » « less
Award ID(s):
1637450
PAR ID:
10300565
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Journal of Climate
Volume:
33
Issue:
18
ISSN:
0894-8755
Page Range / eLocation ID:
7897 to 7908
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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