CO2 CLIMATE SENSITIVITY AND SNOW-SEA-ICE ALBEDO PARAMETERIZATION IN AN ATMOSPHERIC GCM COUPLED TO A MIXED-LAYER OCEAN MODEL

被引:90
作者
MEEHL, GA
WASHINGTON, WM
机构
[1] National Center for Atmospheric Research, Boulder, 80307-3000, CO
关键词
D O I
10.1007/BF00144505
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
The snow-sea-ice albedo parameterization in an atmospheric general circulation model (GCM), coupled to a simple mixed-layer ocean and run with an annual cycle of solar forcing, is altered from a version of the same model described by Washington and Meehl (1984). The model with the revised formulation is run to equilibrium for 1 × CO2 and 2 × CO2 experiments. The 1 ×CO2 (control) simulation produces a global mean climate about 1° warmer than the original version, and sea-ice extent is reduced. The model with the altered parameterization displays heightened sensitivity in the global means, but the geographical patterns of climate change due to increased carbon dioxide (CO2) are qualitatively similar. The magnitude of the climate change is affected, not only in areas directly influenced by snow and ice changes but also in other regions of the globe, including the tropics where sea-surface temperature, evaporation, and precipitation over the oceans are greater. With the less-sensitive formulation, the global mean surface air temperature increase is 3.5 °C, and the increase of global mean precipitation is 7.12%. The revised formulation produces a globally averaged surface air temperature increase of 4.04 °C and a precipitation increase of 7.25%, as well as greater warming of the upper tropical troposphere. Sensitivity of surface hydrology is qualitatively similar between the two cases with the larger-magnitude changes in the revised snow and ice-albedo scheme experiment. Variability of surface air temperature in the model is comparable to observations in most areas except at high latitudes during winter. In those regions, temporal variation of the sea-ice margin and fluctuations of snow cover dependent on the snow-ice-albedo formulation contribute to larger-than-observed temperature variability. This study highlights an uncertainty associated with results from current climate GCMs that use highly parameterized snow-sea-ice albedo schemes with simple mixed-layer ocean models. © 1990 Kluwer Academic Publishers.
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页码:283 / 306
页数:24
相关论文
共 32 条
[1]  
BATES GT, 1986, MON WEATHER REV, V114, P687, DOI 10.1175/1520-0493(1986)114<0687:TEOCCO>2.0.CO
[2]  
2
[3]   A METHODOLOGY FOR UNDERSTANDING AND INTERCOMPARING ATMOSPHERIC CLIMATE FEEDBACK PROCESSES IN GENERAL-CIRCULATION MODELS [J].
CESS, RD ;
POTTER, GL .
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 1988, 93 (D7) :8305-8314
[4]   ICE-ALBEDO FEEDBACK IN A CO2-DOUBLING SIMULATION [J].
DICKINSON, RE ;
MEEHL, GA ;
WASHINGTON, WM .
CLIMATIC CHANGE, 1987, 10 (03) :241-248
[5]  
HIBLER WD, 1979, J PHYS OCEANOGR, V9, P815, DOI 10.1175/1520-0485(1979)009<0815:ADTSIM>2.0.CO
[6]  
2
[7]   MODELING CLIMATE CHANGE - AN ASSESSMENT OF SEA ICE AND SURFACE ALBEDO FEEDBACKS [J].
INGRAM, WJ ;
WILSON, CA ;
MITCHELL, JFB .
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 1989, 94 (D6) :8609-8622
[8]  
MANABE S, 1975, J ATMOS SCI, V32, P3, DOI 10.1175/1520-0469(1975)032<0003:TEODTC>2.0.CO
[9]  
2
[10]  
MANABE S, 1987, J ATMOS SCI, V44, P1211, DOI 10.1175/1520-0469(1987)044<1211:LSCOSW>2.0.CO