Dynamical versus statistical downscaling for the generation of regional climate change scenarios at a Western Mediterranean basin: the Jucar River District

[EN] Current climate change (CC) predictions for the Western Mediterranean show a significant increase in temperature, and a decrease in precipitations, with great variability depending on general circulation models (GCM) and downscaling approaches. This paper analyses how dynamic downscaling improv...

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Detalles Bibliográficos
Autores: Chirivella Osma, Vicente, Capilla Romá, José Esteban|||0000-0002-3399-4596, Pérez-Martín, Miguel Ángel|||0000-0002-4733-0862
Tipo de recurso: artículo
Fecha de publicación:2016
País:España
Institución:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/97910
Acceso en línea:https://riunet.upv.es/handle/10251/97910
Access Level:acceso abierto
Palabra clave:Climate change
Convective precipitation
Downscaling
Jucar River Basin
Non-convective precipitation
Western Mediterranean
TECNOLOGIA DEL MEDIO AMBIENTE
INGENIERIA HIDRAULICA
FISICA APLICADA
Descripción
Sumario:[EN] Current climate change (CC) predictions for the Western Mediterranean show a significant increase in temperature, and a decrease in precipitations, with great variability depending on general circulation models (GCM) and downscaling approaches. This paper analyses how dynamic downscaling improves statistically based CC scenarios. The study area was the Jucar River Basin (JB), with results from ECHAM5 GCM, and a close time frame of 2010-2040 appropriated for decision-making. The dynamic downscaling was performed with the regional climate model (RCM) RegCM3. It was applied to a coarse grid over the Iberian Peninsula, and then to a finer grid over the JB. The RCM was customized to reproduce Western Mediterranean climatic conditions using the convective precipitation scheme of Grell; the non-convective scheme was customized by changing the default RHmin and C-ptt parameters to reproduce precipitations originated by larger-scale atmospheric circulations. The RCM results, compared to current official Spanish Agency of Meteorology (AEMET) scenarios-statistically based-reproduce much better historical data (used to verify scenarios generation). They foresee a 21.0% precipitation decrease for 2010-2040, compared to previous ECHAM4 predictions with statistical downscaling (-6.64%). The most significant reductions are in February, September and October. Average estimated temperature increase is 0.75 degrees C, with high increments in July (+3.05 degrees C) and August (+1.89 degrees C).