Severe droughts over South America: sea surface temperature impacts in the present and future climate

Abstract

The Sea Surface Temperature (SST) impact on atmospheric circulation regime over the continents is one of the scientific questions related to the climate in the future that have received more attention in the last years. This information can be directly applied on climate prediction improvement, helping many sectors of human activities such as the energy generation, economy, agriculture, farming and others. SST fluctuations in austral oceanic basins, particularly on the South Atlantic Ocean (SAO) may result in extreme droughts over the South American continent. Although these extremes can cause significant damages for the society, they are not fully addressed yet. The recent climate projections from Intergovernmental Panel on Climate Change (IPCC) points to more intense e frequents severe droughts episodes in many parts around the world. This study purposes to investigate how the interaction between the SAO and remote SST anomalies can modify the atmospheric circulation patterns over South America, particularly related to extreme dry conditions. The project intends to use an Atmospheric General Circulation Model (AGCM) to generate numerical experiments initialized with SST forcings from different oceanic basins and in particular for the SAO. Some experiments using the same SST distribution used in the IPCC (2007) GCM runs to simulate future climate scenarios (e.g., A1 and B2) will also be performed. The basic idea is to detect how important they are to modify the South American atmospheric circulation. This project will contribute to the thematic project (08/58101-9) entitled "Impact of the Southwestern Atlantic Ocean on South American Climate for the 20th and 21st centuries" submitted to FAPESP. (AU)