Modeling the effects of climate change on hydrology and sediment load in a headwater basin in the Brazilian Cerrado biome

Abstract

The assessment of hydrological impacts due to a changing climate has been an important tool for supporting future planning and management actions to mitigate these impacts. This study aimed to assess the climate change impacts on streamflow and sediment loads in the Upper Paranaíba river basin (UPRB), Southeastern Brazil. The SWAT model was applied to estimate the streamflow and sediment loads under observed conditions and to quantify possible climate change impacts from a multi-model ensemble and four Regional Climate Models (RCM) under two climate change scenarios. The results showed that simulations from the RCMs indicated reductions in streamflow varying from 27.6 to 75%. In addition, the simulated sediment loads were in agreement with the temporal pattern of streamflow. Besides all the uncertainties involved in climate change impacts simulations, the UPRB would suffer serious problems regarding to the water availability in extreme climatic conditions. As this basin is entirely inserted on the Brazilian Cerrado biome, the results can be useful in the context of eco-hydrological services, such as fresh water availability and identification of the land-use/soil combinations that are more vulnerable to water erosion.