气候变化领域集成服务门户(CCPortal): Weak dependence of future global mean warming on the background climate state

CCPortal

DOI	10.1007/s00382-019-04849-3
	Weak dependence of future global mean warming on the background climate state
	Stolpe M.B.; Medhaug I.; Beyerle U.; Knutti R.
发表日期	2019
ISSN	0930-7575
起始页码	5079
结束页码	5099
卷号	53 期号:2020-07-08
英文摘要	It is debated whether the global mean transient temperature response to forcing is largely independent of biases in the simulated base state climate. To test this, we run the Community Earth System Model (CESM1) into new quasi-equilibria by altering the solar constant by ± 25 Wm−2 and initialize idealized CO2 climate change experiments from these climate states. The simulations branched off from the warm and control states, with increased and unaltered solar constant, respectively, show similar global mean feedback parameters, effective CO2 radiative forcings (ERF) and ocean heat uptake efficiencies and therefore simulate indiscernibly different amounts of global warming. The experiments starting from the cold climate state behave differently: The CO2 ERF is lower mostly because of rapid adjustments in the clouds, and the climate sensitivity is enhanced, mainly due to a large surface albedo feedback caused by the increased sea ice and snow coverage that extends to lower latitudes. The global heat uptake efficiency is reduced in the cold state. While taking up more heat in the Southern Ocean than the experiments from the warmer states much less heat is taken up by the North Atlantic. The less stabilizing net climate feedback parameter and the decreased ocean heat uptake efficiency dominate over the reduced CO2 ERF, and the simulations initialized from the cold state show ~ 10% more global warming compared to those from the control state. This enhanced warming mainly occurs at higher-latitudes over sea ice and snow-covered areas and the North Atlantic. While the local climate response may depend strongly on the base state, the future global mean temperature increase simulated by CESM1 is remarkably independent on the initial climate state. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Climate sensitivity; Meridional overturning circulation; Ocean heat uptake efficiency; Radiative forcing; State-dependence; Transient climate response
语种	英语
scopus关键词	albedo; climate change; global warming; heat flow; heat source; meridional circulation; overturn; radiative forcing; Atlantic Ocean; Atlantic Ocean (North); Southern Ocean
来源期刊	Climate Dynamics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/145935
作者单位	Institute for Atmospheric and Climate Science, ETH Zürich, Zurich, 8092, Switzerland
推荐引用方式 GB/T 7714	Stolpe M.B.,Medhaug I.,Beyerle U.,et al. Weak dependence of future global mean warming on the background climate state[J],2019,53(2020-07-08).
APA	Stolpe M.B.,Medhaug I.,Beyerle U.,&Knutti R..(2019).Weak dependence of future global mean warming on the background climate state.Climate Dynamics,53(2020-07-08).
MLA	Stolpe M.B.,et al."Weak dependence of future global mean warming on the background climate state".Climate Dynamics 53.2020-07-08(2019).