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Title: Changes in Tropical Precipitation Intensity With El Niño Warming
Abstract

Mesoscale convection generates the majority of extreme precipitation in tropical regions. Changes to these precipitation intensities,P, with long‐term modes of climate variability have been hard to assess because they are not well represented in current climate models. Here we stratify a satellite climatology of convective systems by El Niño phase and cloud top temperature. We find that gains (losses) in high precipitation intensity ( 10 mm hr−1) are largest for the deepest (least deep) systems during El Niño relative to La Niña. The surface temperature and wind changes that define El Niño manifest as surface flux changes but are not sufficient to explain thesetrends. We explore also the dynamical component of precipitation generation with a vertical momentum budget. Midtropospheric drying in the vicinity of the deepest systems boosts instability and ascent rates during El Niño, while the strengthened large‐scale ascent minimizes the drag force on their updrafts.

 
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Award ID(s):
1649770
NSF-PAR ID:
10386837
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
47
Issue:
14
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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