Improvement of hydroclimatic projections over Southeast Spain by applying a novel RCM ensemble approach

Climate model outputs can be used as climate forcing for hydrological models to study the impact of climate change on the water cycle. This usually propagates cumulative uncertainties, transferring the errors from the climate models to the hydrological models. Then, methodologies are needed to evalu...

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Detalhes bibliográficos
Autores: Olmos Giménez, Patricia, García Galiano, Sandra Gabriela, Giraldo Osorio, Juan Diego
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2018
País:España
Recursos:Universidad Politécnica de Cartagena(UPCT)
Repositorio:Repositorio Digital UPCT
OAI Identifier:oai:repositorio.upct.es:10317/10357
Acesso em linha:http://hdl.handle.net/10317/10357
https://www.mdpi.com/2073-4441/10/1/52
Access Level:acceso abierto
Palavra-chave:Climate change
Regional climate models
PDF ensemble
Hydrological cycle
Runoff projection
Uncertainties reduction
Hydrological modeling
Ingeniería Hidráulica
2508 Hidrología
Descrição
Resumo:Climate model outputs can be used as climate forcing for hydrological models to study the impact of climate change on the water cycle. This usually propagates cumulative uncertainties, transferring the errors from the climate models to the hydrological models. Then, methodologies are needed to evaluate the impact of climate change at basin scale by reducing the uncertainties involved in the modeling chain. The paper aims to assess the impact of climate change on the runoff, considering a novel approach to build a Regional Climate Model (RCM) ensemble as climate forcing for a parsimonious spatially distributed hydrological model. A semiarid basin of southeast of Spain was selected for the study. The RCM ensembles were built based on seasonal and annual variability of rainfall and temperature. If the runoff projections for 2021–2050 are compared to the 1961–1990 observed period, a significant decrease in runoff equal to −20% (p-value t-test 0.05) was projected. However, by changing the observed period to 1971–2000, a despicable change (2.5%) is identified. This fact demonstrates that trends based on short records are very sensitive to the beginning and end dates, due to the natural variability. Special attention should be paid to the selection of the period for impact studies.