Variabilidade do sistema corrente do Brasil associada aos cenários de mudanças climáticas A1F1 e B1

Abstract

The aim of this work is to investigate the behavior of volume transport and advective heat flux patterns which are related to the Brazil Current System (BCS) according to the climate change scenarios suggested by the Intergovernmental Panel on Climate Changes. The results deriving from the global model Climate Model version 2.1 (GFDL-CM2.1) for future scenarios of climate change A1FI and B1 and for the scenario that represents the climate in the Twentieth Century (20C3M) have been used in this work. Volume transport and advective heat flux integrated for the whole BCS as well as for each water mass which constitutes the system have been calculated applying these data. Estimates were made for three zonal sections (23ºS, 25ºS and 30ºS) and then were used in the Wavelet Analysis. The performed analysis showed the occurrence of interannual variability for the estimated properties in the region. It also showed that the BCS shows changes in both intensity and variability of these parameters when comparing A1FI and B1 to 20C3M. Results from Wavelet Analysis for the total volume transport and advective heat flux integrated per section show that the period between three and six years prevails in sections 23ºS and 25ºS. The variability in 30ºS however, is significantly higher than eight years. It could also be observed the change of the variability of the total volume transport and heat flux temporal series towards higher frequencies when they are submitted to A1FI and B1 climate changes scenarios.