scholarly journals Sea-surface temperature induced variability of the Southern Annular Mode in an atmospheric general circulation model

2004 ◽  
Vol 31 (24) ◽  
Author(s):  
Tianjun Zhou
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
General Circulation Model ◽  
General Circulation ◽  
Atmospheric General Circulation Model ◽  
Circulation Model ◽  
Southern Annular Mode ◽  
Sea Surface ◽  
Annular Mode ◽  
Atmospheric General Circulation

scholarly journals Climatic stability of the geographic origin of Antarctic precipitation simulated by an atmospheric general circulation model

1999 ◽  
Vol 29 ◽  
pp. 45-48 ◽  
Author(s):  
Gilles Delaygue ◽  
Valérie Masson ◽  
Jean Jouzel
Keyword(s):  
General Circulation Model ◽  
General Circulation ◽  
Latitudinal Gradient ◽  
Atmospheric General Circulation Model ◽  
Hydrological Cycle ◽  
Geographic Origin ◽  
Circulation Model ◽  
Sea Surface ◽  
Atmospheric General Circulation ◽  
Antarctic Precipitation

AbstractThe geographic origin of Antarctic precipitation is important for ice-core isotopic interpretation as well as ice-sheet mass-balance calculations. Here we estimate these moisture origins with the NASA/Goddard Institute of Space Studies atmospheric general circulation model, under different climatic conditions. This model reasonably simulates the broad features of the present-day observed hydrological cycle, and indicates a subtropical to subglacial (30-60° S) latitudinal origin for the Antarctic precipitation. We use different climatic reconstructions, all based on CLIMAP, for the Last Glacial Maximum (about 21000 years ago), which differ by the latitudinal sea-surface temperature gradient and seasonality. CLIMAP conditions increase the latitudinal gradient and the sea-ice extent, with the consequence of slightly enhancing the low-latitude origins. Shifting the seasonal cycle of oceanic prescribed conditions has an important effect on the hydrological cycle but less on the precipitation origin. Prescribing cooler tropical sea-surface temperatures, which decreases the latitudinal gradient, makes the latitudinal contributions closer to modern ones and increases the dominant oceanic sources. Globally the origins of Antarctic precipitation do not change significantly, either annually or seasonally.

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