Resilience of Hydrologic Similarity Areas to extreme climate change scenarios in an urban watershed

Abstract

ABSTRACT The water balance resilience to extreme climate change scenarios in Hydrologic Similarity Areas (HSA) is evaluated in the Belém catchment, Brazil. We used HadGEM2-ES statistically downscaled with the CMhyd tool under the Representative Concentration Pathways (RCPs) 2.6 and 8.5 to simulate climate scenarios. The AquaCycle model was used to simulate effects on the water balance. Climate modeling results show an increase in annual precipitation and average temperature, decreased rainy days, and increasing extremes. The water balance modeling demonstrated that the HSAs with higher percentages of impermeable surfaces present greater surface runoff and lower levels of infiltration and actual evapotranspiration increment in both RCP2.6 and RCP8.5. The differences among the HSA responses in the water balance are even more evident when analyzing the extreme events data series. Thereby, the results demonstrate that impermeable areas are less resilient to extreme events provided by climate change scenarios.