%0 Conference Proceedings
%4 cptec.inpe.br/adm_conf/2005/10.13.17.55
%2 cptec.inpe.br/adm_conf/2005/10.13.17.55.49
%T Climate variability over South America and South Atlantic associated to sea surface temperature (SST) anomalies in tropical Pacific and subtropical South Atlantic Oceans
%D 2006
%A Roque da Silva, Felipe das Neves,
%A França, José Ricardo de Almeida,
%A Ribeiro, Laura Alice de Araújo,
%@affiliation Centro Federal de Educação Tecnológica Celso Suckow da Fonseca (CEFET-RJ), Coordenadoria de Meteorologia,
%@affiliation Avenida Maracnã 229, Bloco A, 4º andar, Maracanã. 20271-110 Rio de Janeiro, RJ, Brazil (Roque da Silva),
%@affiliation Universidade Federal do Rio de Janeiro (UFRJ), Centro de Ciências Mateméticas e da Natureza, Instituto de Geociências, Departamento de Meteorologia,
%@affiliation Avenida Brigadeiro Trompowski, s/n, Bloco G, Ilha do Fundão. 21941-590 Rio de Janeiro, RJ, Brazil (França,
%@affiliation Ribeiro)
%@electronicmailaddress feliper@acd.ufrj.br
%@electronicmailaddress jricardo@acd.ufrj.br
%@electronicmailaddress meteoro79@hotmail.com
%E Vera, Carolina,
%E Nobre, Carlos,
%B International Conference on Southern Hemisphere Meteorology and Oceanography, 8 (ICSHMO).
%C Foz do Iguaçu
%8 24-28 Apr. 2006
%I American Meteorological Society (AMS)
%J 45 Beacon Hill Road, Boston, MA, USA
%P 1355-1358
%S Proceedings
%1 American Meteorological Society (AMS)
%K El-Niño, La-Niña, Southern oscillation, climate variability, South Atlantic Convergence Zone (SACZ).
%X The objective of this work is to use the Laboratoire de Météorologie Dynamique (LMD - France) Atmosphere General Circulation Model to investigate the relationship between SST anomalies in Pacific and Atlantic Oceans (in the confluence region of Brazil and Falklands currents) and the climate variability over South America and South Atlantic. Particularly this work has intended to study how the climate in these regions behaves when the position of Brazil and Falklands currents was modified, along with El Niño, La Niña and neutrality situations in the tropical Pacific. Initially it was made a simulation using climatological SSTs (control simulation). Next, idealized scenarios (forced) have been created for simulating the presence of El Niño/La Niña and/or positive/negative SST anomalies in the confluence region of Brazil and Falklands currents (in the other regions SST remains climatological). In fact, in the confluence region, it was used positive SST anomalies to simulate the Brazil current more to the South and negative ones in case of the Falklands currents more to the North. All the simulations (control and forced) have had the same initial conditions. This way, nine simulations have been generated. All of them had been run from October to February using ensemble forecasting technique with ten members each. Results had been generated for December/January/February summer trimester. Initial data correspond to the first ten days of October 1997 proceeding from NCEP (National Centers for Environmental Prediction) reanalysis at 00 UTC. Sea surface temperature (SST) data are from optimum interpolation (OI) analysis. This data correspond the monthly means between 1971 and 2000 and they had been interpolated to daily values to force the model. Both initial and boundary data had been interpolated to the model grid. Results show that the greatest effect of SST anomalies in the confluence region occur in the SACZ region. Positive SST anomalies tend to diminish precipitation in the SACZ region, while negative SST anomalies cause an increase in this region. These alterations are linked to changes in pressure patterns in this region. In relation to the joint effect of El Niño and positive/negative SST anomalies in the Atlantic, increase of precipitation in the SACZ region was evidenced in both cases. Similar results had been found for La Niña and positive/negative SST anomalies in the Atlantic.
%9 Role of the SH oceans in climate
%@language en
%3 557-562.pdf