Warming asymmetry in climate change simulations

被引:370
作者
Flato, GM [1 ]
Boer, GJ [1 ]
机构
[1] Univ Victoria, Canadian Ctr Climate Modelling & Anal, Atmospher Environm Serv, Victoria, BC V8W 2Y2, Canada
关键词
D O I
10.1029/2000GL012121
中图分类号
P [天文学、地球科学];
学科分类号
07 ;
摘要
Climate change simulations made with coupled global climate models typically show a marked hemispheric asymmetry with more warming in the northern high latitudes than in the south. This asymmetry is ascribed to heat uptake by the ocean at high southern latitudes. A recent version of the CCCma climate model exhibits a much more symmetric warming, compared to an earlier version, and agrees somewhat better with observed 20th century trends, This is associated with an improved parameterization of ocean mixing which results in a decrease in heat penetration into the Southern Ocean, in accord with earlier ocean-only and simple coupled model investigations. The global average warming and the net penetration of heat into the global ocean (and hence its thermal expansion) are essentially unchanged. Observed trends in sea-ice extent over the past two decades exhibit hemispheric asymmetry with a statistically significant decrease in northern but not in southern ice cover. Both model versions are consistent with these observations implying that observed ice extent is not yet an indicator of asymmetry in future global warming. Taken together, these results suggest that southern hemisphere climate warming at a rate comparable to that in the northern hemisphere should be considered a realistic possibility.
引用
收藏
页码:195 / 198
页数:4
相关论文
共 23 条
[1]   A transient climate change simulation with greenhouse gas and aerosol forcing: experimental design and comparison with the instrumental record for the twentieth century [J].
Boer, GJ ;
Flato, G ;
Reader, MC ;
Ramsden, D .
CLIMATE DYNAMICS, 2000, 16 (06) :405-425
[2]   A transient climate change simulation with greenhouse gas and aerosol forcing: projected climate to the twenty-first century [J].
Boer, GJ ;
Flato, G ;
Ramsden, D .
CLIMATE DYNAMICS, 2000, 16 (06) :427-450
[3]   Observed hemispheric asymmetry in global sea ice changes [J].
Cavalieri, DJ ;
Gloersen, P ;
Parkinson, CL ;
Comiso, JC ;
Zwally, HJ .
SCIENCE, 1997, 278 (5340) :1104-1106
[4]   The Canadian Centre for Climate Modelling and Analysis global coupled model and its climate [J].
Flato, GM ;
Boer, GJ ;
Lee, WG ;
McFarlane, NA ;
Ramsden, D ;
Reader, MC ;
Weaver, AJ .
CLIMATE DYNAMICS, 2000, 16 (06) :451-467
[5]  
FLATO GM, 1992, J PHYS OCEANOGR, V22, P626, DOI 10.1175/1520-0485(1992)022<0626:MPIAAC>2.0.CO
[6]  
2
[7]  
GENT PR, 1990, J PHYS OCEANOGR, V20, P150, DOI 10.1175/1520-0485(1990)020<0150:IMIOCM>2.0.CO
[8]  
2
[9]   Global warming in a coupled climate model including oceanic eddy-induced advection [J].
Hirst, AC ;
Gordon, HB ;
OFarrell, SP .
GEOPHYSICAL RESEARCH LETTERS, 1996, 23 (23) :3361-3364
[10]  
Jackett DR, 2000, J CLIMATE, V13, P1384, DOI 10.1175/1520-0442(2000)013<1384:TEIOAC>2.0.CO