An integrated modelling and remote sensing approach for hydrological study in arid and semi‐arid regions: the SUDMED Programme

Abstract

Recent efforts have been concentrated in the development of models to understand and predict the impact of environmental changes on hydrological cycle and water resources in arid and semi-arid regions. In this context, remote sensing data have been widely used to initialize, to force or to control the simulations of these models. However, for several reasons, including the difficulty in establishing relationships between observational and model variables, the potential offered by satellite data has not been fully used. As a matter of fact, a few hydrological studies that use remote sensing data emanating from different sources (sensors, platforms) have been performed. In this context, the SUDMED program has been designed in 2002 to address the issue of improving our understanding about the hydrological functioning of the Tensift basin which is a semi-arid basin situated in central Morocco. The first goal is model development and/or refinement, for investigating the hydrological responses to future scenario about climate change and human pressure. The second aim is the effective use of remote sensing observations in conjunction with process models, to provide operational prognostics for improving water resource management. The objective of this paper is to present the SUDMED program, its objectives and its thrust areas, and to provide an overview of the results obtained in the first phase of the program (2002)(2003)(2004)(2005)(2006). Finally, the lessons learned, future objectives and the unsolved issues are presented.

Intercomparison of four remote-sensing-based energy balance methods to retrieve surface evapotranspiration and water stress of irrigated fields in semi-arid climate

“…In semi-arid areas, more than 80 % of the annual available water is lost through evapotranspiration (Chehbouni et al, 2008a). In most countries, and especially the least developed ones, irrigation consumes the largest amount of water.…”

Performance Metrics for Soil Moisture Downscaling Methods: Application to DISPATCH Data in Central Morocco

“…The approach is tested using a disaggregated soil moisture dataset and in situ measurement time series collected during the 2010-2013 period at six locations in the Haouz plain, central Morocco [35][36][37][38]. The downscaled dataset is obtained from the disaggregation of 40-km resolution SMOS soil moisture at 1-km resolution using MODIS data and DISPATCH (disaggregation based on physical and theoretical scale change; [17,18]) methodology.…”

“…In the framework of the SudMedresearch program [37] and of Télédétection et Ressources en Eau en Méditerranée semi-Aride (TREMA) Joint International Laboratory, several flux and meteorological stations were deployed over the dominant vegetation types (olive, orange, apricot, beet and wheat) and under different irrigation methods (drip and flooding) with the objective to understand the processes that affect the water and energy balances of semi-arid areas at the basin scale. Monitoring stations were set up for several years at orchards sites and for the whole crop cycle (sowing, vegetative growth, full canopy and senescence) at annual crop (mostly wheat and beet) sites [37,38].…”

“…Monitoring stations were set up for several years at orchards sites and for the whole crop cycle (sowing, vegetative growth, full canopy and senescence) at annual crop (mostly wheat and beet) sites [37,38]. Since the SMOS launch in November 2009, six stations have operated with two in orchard fields and four in annual crop fields.…”

Coupling soil-vegetationatmosphere- transfer model with energy balance model for estimating energy and water vapor fluxes over an olive grove in a semi-arid region

“…Additionally, the validation of the model will be performed over an extended period (measurements taken over approximately one year) in order to test its consistency for accurately estimating heat fluxes under all weather conditions. Data used in these investigations were collected within the framework of the SUDMED project, 10 ity of water needs and consumption for irrigated crops under water shortages.…”