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  • The influence of internal variability on Earth's energy balance framework and implications for estimating climate sensitivity
Title: The influence of internal variability on Earth's energy balance framework and implications for estimating climate sensitivity
Abstract. Our climate is constrained by the balance between solar energy absorbed by the Earth and terrestrial energy radiated tospace. This energy balance has been widely used to infer equilibrium climate sensitivity (ECS) from observations of20th-century warming. Such estimates yield lower values than other methods, and these have been influential in pushing downthe consensus ECS range in recent assessments. Here we test the method using a 100-member ensemble of the Max Planck Institute Earth System Model(MPI-ESM1.1) simulations of the period 1850–2005 with known forcing. We calculate ECS in each ensemble member usingenergy balance, yielding values ranging from 2.1 to 3.9K. The spread in the ensemble is related to the centralassumption in the energy budget framework: that global average surface temperature anomalies are indicative of anomaliesin outgoing energy (either of terrestrial origin or reflected solar energy). We find thatthis assumption is not well supportedover the historical temperature record in the model ensemble or more recent satellite observations. We find that framingenergy balance in terms of 500hPa tropical temperature better describes the planet's energy balance.  more » « less
Award ID(s):
1661861
PAR ID:
10090445
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Atmospheric Chemistry and Physics
Volume:
18
Issue:
7
ISSN:
1680-7324
Page Range / eLocation ID:
5147 to 5155
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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