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Current and planned Project with the Regional Climate Model Regional climate simulations over southern South America and sensitivity experiments. Silvina A. Solman CIMA – CONICET/UBA Buenos Aires, Argentina. Interest in using Regional Climate Models:.
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Current and planned Project with the Regional Climate ModelRegional climate simulations over southern South America and sensitivity experiments Silvina A. Solman CIMA – CONICET/UBA Buenos Aires, Argentina
Interest in using Regional Climate Models: • To generate regional climate change scenarios over southern South America to improve information on the climate conditions under which natural and human systems will be exposed. • To study the sensitivity of climate to surface conditions, mainly soil moisture and sea surface temperatures, in particular, their impact on precipitation anomalies over southern South America.
1 The AOGCM/IPSL global model (France) will be used to simulate changes in climate due to the SRES A2 emission scenario. resolution of about 5º by 5º simulation for the period 1860 – 2100 . 2 The AGCM LMDZ global model adapted at CIMA (with a variable horizontal resolution with a zoom centred over South America) driven by sea surface temperature, sea ice and CO2 provided by the AOGCM/IPSL model will be used to simulate changes in climate. resolution of about 1º by 1º over South America. Two time-slice experiments (10 yrs) Regional climate change scenarios over southern South America
Regional climate change scenarios over southern South America 3 • In this step a second regionalization will be performed. The use of a regional climate model driven by boundary conditions generated in the previous step, will provide high resolution simulations for the particular area of interest (Argentina).
Sensitivity of climate to surface conditions • Sensitivity of climate to surface conditions, mainly soil moisture and sea surface temperatures. The focus is to what extent soil moisture and sea surface temperature conditions impact on precipitation anomalies over southern South America, in terms of its interannual variability.
Regional climate simulations over southern South America using MM5: Some preliminary results • Simulation of present-day summertime climate with ´perfect´ boundary conditions: Initial and boundary conditions from 6-hourly NCEP reanalysis. • Five 31 days simulations for January (1997-2001).
Ideally, the domain should be large enough to allow full development of internal mesoscale circulations and include relevant regional forcings • Horizontal resolution 60 km • 23 vertical levels • high-resulution planetary boundary layer (Blackadar, 1976) • Kain-Fritssch(1983) cumulus convection • explicit moisture scheme (Dudhia 1989) • Bucket soil moisture scheme With the present domain, the RCM simulations do not diverge from the analyses used to drive the model
Average precipitation for January (1997-2001) in mm/day from Xie and Arkin (a) and MM5 (b) (b) (a)