Influência das mudanças climáticas no balanço hídrico dos lagos de abastecimento de Belém-PA

Abstract

Climate change, projected for global water resources, drastic changes in patterns of distribution and availability of water. So, the objective of this study was to investigate the impacts that climate change will have on the local hydrological cycle. And analyze if the lakes Bolonha and Água Preta, responsible for supplying part of the city of Belém-PA, will be able to provide water to future demand. Then, the water balance of the lakes was projected until 2100, using the GCMs MIROC5 and HADGEM2-ES aligned to the RCM Eta, from two greenhouse gas emission scenarios RCPs 4.5 and 8.5. It was necessary to carry out the projection of the population of the city of Belém-PA until the year 2100, using the Gompertz model. The results projected a large reduction in the volume of precipitation in the rainy months compared to historical data; and for the summer period, the projections point to drier months than normal. The surface evaporation projection showed an increase in the evaporated surface volume. The consequences of the projections on the future water balance of the lakes were a high reduction in the volume of both, interfering in the recovery of their maximum capacities. The projections of future scenarios for the lakes showed that the actual production of COSANPA will not be able to meet the future demand of society, causing a situation of water scarcity until the end of the century, will lead to the need to increase the pumping of water to the lakes. In this way, understanding how changes in hydrological variables will affect water availability is an important tool in the quest to mitigate impacts and carry out long term planning and management of this resource.