Reservoir Management Using Coupled Atmospheric and Hydrological Models: The Brazilian Semi-Arid Case

Water Resour Manage (2012) 26:13651385

DOI 10.1007/s11269-011-9963-2

Jos Maria Brabo Alves & Jos Nilson B. Campos & Jacques Servain

Received: 4 August 2010 /Accepted: 22 December 2011 /

Published online: 11 January 2012# Springer Science+Business Media B.V. 2012

Abstract This study investigated the sensitivity of a dynamic downscaling atmospheric model system coupled with a rainfall-runoff model to hindcast an example of reservoir water management in the semi-arid region of Northeast Brazil (NEB). A regional atmospheric spectral model (RSM) is driven by the outputs of an atmospheric general circulation model (AGCM), itself forced by the observed sea surface temperature over the World Ocean. Daily precipitation simulated by the RSM was then used as the input to a hydrological rainfall-runoff model for the Upper Jaguaribe River Basin to estimate inflows at the Ors Reservoir in the state of Cear. A hindcast analysis of precipitation was performed during the rainy season over NEB (January to June) from 1971 to 2000. The RSM captured the precipitation variability relatively well when a probability density function (PDF) was used to correct the numerical bias. Three hindcast series of inflow using (i) the observed rainfall, (ii) the simulated rainfall before the PDF correction, and (iii) the simulated rainfall after the PDF correction were performed during the study period and then compared to the series of observed inflow. The atmospheric-rainfall-runoff cascade model efficiency was evaluated by comparing the Ors Reservoir release decisions from different scenarios based on observed, simulated (RSM, RSM-PDF), and mean historical reservoir inflows. The cascade model has the potential, relatively well balanced during dry, normal or wet years, to be a

J. M. B. Alves (*)

Fundao Cearense de Meteorologia e Recursos Hdricos (FUNCEME), Av. Rui Barbosa 1246, Aldeota, 60115-221 Fortaleza, CE, Brazile-mail: [email protected]

J. N. B. Campos

Departamento de Engenharia Hidrulica e Ambiental - Centro de Tecnologia, Universidade Federal do Cear (UFC), Fortaleza, Cear, Brazil

J. Servain

Institut de Recherche pour le Dveloppement (IRD), UMR-182, Paris, France

Present Address:J. Servain

Fundao Cearense de Meteorologia e Recursos Hdricos (FUNCEME), Av. Rui Barbosa 1246, Aldeota, 60115-221 Fortaleza, CE, Brazil

Reservoir Management Using Coupled Atmosphericand Hydrological Models: The Brazilian Semi-Arid Case

1366 J.M.B. Alves et al.

useful tool to correctly forecast the decision managements of reservoirs in the semi-arid region of NEB....