Climate change and model parameter uncertainties propagated to ungauged reservoir catchments in Ceará: a study for water availability assessment

• Ano de defesa: 2020
• Autor(a) principal: Estácio, Ályson Brayner Sousa
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Recursos hídricos; Mudanças climáticas; Disponibilidade hídrica; Regionalização; Parameter uncertainty; Conceptual hydrological model
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/50591

Climate change is expected tohave extensive socioeconomic consequences. However, only a fewstudies have assessed the impact of future streamflow modelling uncertaintiesin water availability of complex reservoir network systems.This issue is aggravatedwhen the reservoirs do not have inflow measurement. In these cases,regionalizing the hydrological model parameters is a common approach to streamflowestimation. However, propagating these uncertainties to ungaugedcatchments figuresas a methodological question that remains unsolved.In this study we propose a regionalization procedure based onK-Nearest-Neighbor (K-N-N) classification method, that allowsto incorporateexplicitlythemodel parameter uncertainty.Climate change and model parameter uncertainties were propagated to ungauged reservoir catchments in Cearáand the future water availability of the Jaguaribe Metropolitan hydrossystemwas assessed. Eight Global Circulation Models (GCMs) from the sixth phaseofthe Coupled Model Intercomparison Project(CMIP6) were used to represent future climate. The K-Nearest-Neighbours regionalizationproduced accurate streamflow prediction with an average NSE of 0.67, when only the first neighbour is used.Half of GCMsforecasted a significant increase of water availability for the period 2021-2050in the hydrosystem, while the other half forecasteddecrease or maintenance. Parameter uncertainty showed to be negligible in comparison to climate change uncertainty. The proposed framework is expected to collaborate with uncertainty assessment in Ceará, as a tool for water resources planning and management.