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Title: Oceanic Influence and Lapse Rate Changes Dominate the Recent Amplified Saharan Warming
Abstract The surface air temperature (SAT) over the Sahara Desert has increased at a much faster rate than average tropical land in recent decades. This study examines the relative roles of anthropogenic greenhouse gas (GHG) forcing and sea surface temperature (SST) change in the observed Saharan temperature increase during boreal warm season from 1979 to 2020 using atmospheric general circulation model simulations. It is found that the SST forcing dominates the observed Saharan warming. Further analysis shows that the warming ocean forces the Saharan SAT increase by moving more energy to the Sahara Desert, while the water vapor feedback plays a secondary role. The reason for the stronger Saharan warming than the average tropical land given the same SST forcing is also explored. We found that the largest contributor to the warming contrast is the lapse‐rate feedback, which is attributable to the difference in the vertical warming profile.  more » « less
Award ID(s):
1952745
PAR ID:
10536299
Author(s) / Creator(s):
;
Publisher / Repository:
the American Geophysical Union
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
51
Issue:
2
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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