Reconstruction of the extreme precipitation events variability based on high-resolution analyses (´18 O, ´13 C and trace elements) in speleothems from Lage Branca and Malfazido cave in Southeast of Brazil

Abstract

Extreme precipitation events represent the major source of risk associated to the interannual variability in the regions of tropical climate and have been becoming increasingly frequent and intense in modern times. In Brazil, around 74% of deaths related to natural disasters are associated with events of extreme rainfall. Facing the recent hydroclimatic changes in South America, is has become necessary to comprehend how the variability in climatic conditions interferes with the frequency and magnitude of these events. However, due to limited instrumental data record,reconstructing the hydroclimate history has been difficult, which brings the focus onto paleoclimate records based on high-resolution proxies (´ 18 O and trace elements) from speleothems, once extreme rainfall events can cause subsurface flooding, leading the caves in particular to become a promising domain for the reconstruction of paleo flood activities. Therefore, the current research plan has the goal to understand how paleo floods correlate to extreme paleoclimatic changes during late Holocene (~2 thousand years) over Southeast Brazil.To better understand how the climate forcings can influence in the frequency of extreme precipitation events, records of speleothems from the last millennium and from the Holocene are being developed for the southeast of Brazil. Those records will allow us to understand how the frequency of those events are related with others climatic factors and forcings. (AU)