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Title: It’s the Heat and the Humidity: The Complementary Roles of Temperature and Specific Humidity to Recent Changes in the Energy Content of the Near‐Surface Atmosphere
Abstract

Global climate change is a change in the planetary energy (E) balance. It is usually expressed as a change in near‐surface air temperature (Ta), but changes in energy content due toTa(ET) represent only part of the near‐surface energy balance, which also includesEchanges due to specific humidity (ESH). We analyzed MERRA‐2 and ERA5 reanalysis data and 15 CMIP6 Atmospheric Model Intercomparison Project (AMIP) models from 1980 to 2014. Some 44%, 39%, and 50% of MERRA‐2 pixels showed significant increases inET,ESH, andE, respectively. The average increase inET(ESH) was 16.9 (13.6) J kg−1 year−1, but AMIP models estimated larger averageET(21.6 J kg−1 year−1) andESH(16.7 J kg−1 year−1). GlobalTawould have increased at nearly double the observed rate if energy was not partitioned into latent heat. Results demonstrate the critical role that specific humidity plays in recent climate changes.

 
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NSF-PAR ID:
10369642
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
49
Issue:
4
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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