Naturalized streamflows and Affluent Natural Energy projections for the Brazilian hydropower sector for the SSP2-4.5 and SSP5-8.5 scenarios of the CMIP6

Abstract

Climate change projects an increase in extreme weather events in the coming decades, which could significantly affect Brazil's water and energy security. Thus, this study sought to analyze possible impacts of climate change on the projections of naturalized streamflows and Affluent Natural Energy (ANE) for the Brazilian hydropower sector utilizing five models of the Coupled Model Intercomparison Projects version 6 (CMIP6), based on SSP-4.5 and SSP-8.5 scenarios for the 21st century. Naturalized streamflows for the 24 stations representing the National Interconnected System (NIS) were estimated through the concentrated hydrological model SMAP (Soil Moisture Accounting Procedure), while the streamflows for the other stations that comprise the NIS were obtained by linear regression. The streamflows, as well as the productivity of the reservoirs, were used to calculate the ANE. The results showed that most of the models project possible reductions in annual naturalized streamflows and ANE for the three periods analyzed and for the North, Northeast, and Southeast/Midwest sectors of Brazil. Meanwhile, the Northern and Southern sectors, for the period 2080–2099, most of the models indicated an increase of annual, precipitation, naturalized streamflows and ANE. HIGHLIGHTS Most of the CMIP6 models showed that the NIS reservoirs are sensitive to increasing greenhouse gas emissions.; The medians of the standardized anomalies of annual naturalized streamflows and ANE indicated an increase for the South and North sectors of the country.; In the Northeast subsystem, most of the CMIP6 models indicated a reduction in naturalized streamflows and ANE.;

Keywords

• ane
• brazilian hydropower sector
• climate change
• cmip6
• streamflow