Paleoclimate and calibration study of karst system in central Brazil: implication for paleoclimate studies based on speleothem records

Abstract

The South Atlantic Convergence Zone concentrates most of the precipitation associated to the Southern American monsoon. Variations in the strength and position of the of this important climate feature account for most of the regional precipitation variability over Brazil during summer monsoons. Paleoclimate studies based on speleothem records suggest that variation in solar insolation and ocean circulation plays an important role in controlling the moisture transport along the South Atlantic Convergence Zone, causing important impacts in rainfall distribution over central Brazil. However, as a whole, far too little is known about paleoclimate changes in regions that encompasses important endemics centers, such as the Atlantic forest biome located in Southern Bahia. In this context, this project aims to determine patterns of climate change over regions located in the phytogeographic domains of Atlantic forest in order to establish scenarios for species dispersion between this biome and the Amazon through areas currently occupied by Cerrado and Caatinga vegetation. Our results are essential to support research projects currently in progress in the field of biogeography and biodiversity (FAPESP: 2013 / 50297-0; 2012 / 03942-4; 2011/1203-4). In order to obtain a better understanding of the speleothem stable isotope time series, it intends to conduct a systematic monitoring program involving measurements of environmental, hydrologic and isotopic parameters on meteoric water in areas from Southeastern Bahia.