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Title: Relationships Between Tropical Ascent and High Cloud Fraction Changes With Warming Revealed by Perturbation Physics Experiments in CAM5
Abstract

Tropical ascent area (Aa) and high cloud fraction (HCF) are projected to decrease with surface warming in most Coupled Model Intercomparison Project Phase 5 (CMIP5) models. Perturbing deep convective parameters in the Community Atmosphere Model (CAM5) results in a similar spread and correlation between HCF andAaresponses to interannual warming compared to the CMIP5 ensemble, with a narrowerAacorresponding to greater HCF reduction. Perturbing cloud physics parameters produces a comparatively smaller range ofAaresponses to warming and a dissimilar HCF‐Aarelation to that in CMIP5; a narrowerAacorresponds to less HCF reduction, likely due to cloud radiative effects. A narrowing ofAacorresponds to a regime shift toward stronger precipitation in both experiments. We infer that model differences in deep convection parameterization likely play a greater role than differing cloud physics in determining the diverse responses ofAaand HCF to warming in CMIP5.

 
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NSF-PAR ID:
10375357
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
46
Issue:
16
ISSN:
0094-8276
Page Range / eLocation ID:
p. 10112-10121
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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