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Title: Connecting Hemispheric Asymmetries of Planetary Albedo and Surface Temperature
Satellite measurements show that the Northern and Southern hemispheres reflect equal amounts of shortwave radiation (“albedo symmetry”), but no theory exists on if, how, and why the symmetry is established and maintained. Ambiguously, climate models are strongly biased in albedo symmetry but agree in the sign of the response to CO2. We find that mean‐state biases in albedo symmetry and hemispheric surface temperature asymmetry correlate negatively. Similarly, the response of albedo asymmetry to CO2forcing correlates negatively with the magnitude of the asymmetry in surface warming. This is true across many and within single climate model simulations: a too warm or stronger warming hemisphere is darker or darkens more than its counterpart. In the 21 years of observations we find the same tendency and hypothesize (a) albedo symmetry is a function of the current climate state and (b) we will observe an evolution toward albedo asymmetry in coming decades.  more » « less
Award ID(s):
2233673
PAR ID:
10486075
Author(s) / Creator(s):
;
Publisher / Repository:
AGU
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
50
Issue:
6
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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