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Title: Are the Transient and Equilibrium Climate Change Patterns Similar in Response to Increased CO2?
Abstract After a CO 2 increase, whether the early transient and final equilibrium climate change patterns are similar has major implications. Here, we analyze long-term simulations from multiple climate models under increased CO 2 , together with the extended simulations from CMIP5, to compare the transient and equilibrium climate change patterns under different forcing scenarios. Results show that the normalized warming patterns (per 1 K of global warming) are broadly similar among different forcing scenarios (including abrupt 2 × CO 2 , 4 × CO 2 , and 1% CO 2 increase per year) and during different time periods, except for the first 50 years or so when warming is weaker over the North Atlantic and Southern Ocean but stronger over most continents. During the first 200 years, this consistency is stronger over land than over ocean, but is lower in midlatitudes than other regions. Normalized precipitation change patterns are also similar, albeit to a lesser degree, among different forcing scenarios and across different time periods, although noticeable differences exist during the first few hundred years with smaller increases over the tropical Pacific. Precipitation over many subtropical oceans and land areas decreases consistently under different forcing scenarios and over all more » time periods. In particular, the transient and near-equilibrium change patterns for both surface air temperature and precipitation are similar over most of the globe, except for the North Atlantic warming hole, which is mainly a transient feature. The Arctic amplification and land–ocean warming contrast are largest during the first 100–200 years after CO 2 quadrupling but they still exist in the equilibrium response. « less
Authors:
; ;
Award ID(s):
1743738
Publication Date:
NSF-PAR ID:
10233630
Journal Name:
Journal of Climate
Volume:
33
Issue:
18
Page Range or eLocation-ID:
8003 to 8023
ISSN:
0894-8755
Sponsoring Org:
National Science Foundation
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