Envisat/ASAR Images for the Calibration of Wind Drag Action in the Doñana Wetlands 2D Hydrodynamic Model

Abstract

Doñana National Park wetlands are located in southwest Spain, on the right bank of the Guadalquivir River, near the Atlantic Ocean coast. The wetlands dry out completely every summer and progressively flood again throughout the fall and winter seasons. Given the flatness of Doñana's topography, the wind drag action can induce the flooding or emergence of extensive areas, detectable in remote sensing images. Envisat/ASAR scenes acquired before and during strong and persistent wind episodes enabled the spatial delineation of the wind-induced water displacement. A two-dimensional hydrodynamic model of Doñana wetlands was built in 2006 with the aim to predict the effect of proposed hydrologic restoration actions within Doñana's basin. In this work, on-site wind records and concurrent ASAR scenes are used for the calibration of the wind-drag modeling by assessing different formulations. Results show a good adjustment between the modeled and observed wind drag effect. Displacements of up to 2 km in the wind direction are satisfactorily reproduced by the hydrodynamic model, while including an atmospheric stability parameter led to no significant improvement of the results. Such evidence will contribute to a more accurate simulation of hypothetic or design scenarios, when no information is available for the atmospheric stability assessment.

Long-Term Monitoring of the Flooding Regime and Hydroperiod of Doñana Marshes with Landsat Time Series (1974–2014)

“…The relationship with the marsh Digital Elevation Model derived from LiDAR [66] showed a tight correlation between microtopography and hydroperiod (r 2 = 0.90, p < 0.001). The remaining unexplained variability might well reflect the wind drag effects that have been described in such a shallow wetland [25].…”

“…Alternatively, many studies have relied on microwave imagery to map flood levels [24][25][26][27]. Radar sensors have several advantages over optical and thermal ones that make them particularly applicable to monitoring hydrologic conditions of wetlands.…”

Balances de agua y calor en la marisma de Doñana

“…Tras el accidente minero de Aznalcóllar en 1998, se intensificó la recuperación de la cantidad y calidad de las aportaciones hídricas a la marisma, así como de su funcionalidad hidrológica natural. El instituto de investigación Flumen UPC-CIMNE ha participado en esta labor mediante la implementación del modelo numérico bidimensional Iber, que permite conocer los campos de velocidades y profundidades de agua en la marisma ante diferentes escenarios de simulación Bladé et al, 2014;Ramos-Fuertes et al, 2014). También ha participado en el seguimiento de masas de agua y comunidades vegetales mediante teledetección (Martí-Cardona et al, 2010;Marti-Cardona, 2014) y en el estudio hidrometeorológico y de flujos de agua y calor en superficie y fondo (Prats et al, 2011(Prats et al, , 2012Ramos Fuertes, 2012).…”

Comparative Hydrodynamic Analysis by Using Two−Dimensional Models and Application to a New Bridge

“…Other publications investigate specific topics, such as the analysis of flooding scenarios in general [21], flood forecasting using coupled hydrological and hydraulic Models [22], extreme flood inundation in coastal river reaches [23], sensitivity of flood loss estimates for building representation and flow depth attribution methods in micro−scale flood modeling [24], real-time prediction of flood inundation [25], numerical distributed modeling of sedimentary and erosion processes [26], soil erosion predictions [27], bedload transport for mixed flows [28], sediment transport during the breakage of dams [29], drying and transport processes in distributed hydrological modeling [30], wood transport and sediment in rivers, flash floods, etc. [31][32][33][34][35][36], hydrodynamic movement in water bodies due to wind drag action [37], inundation modeling in coastal urban areas [38], local rainfall dynamics and uncertain boundary conditions [39,40], conservation of the cultural heritage due to flood risk [41], historical reconstruction [25], hazard mapping [42], research on the rivers confluence in order to analyze the geomorphic consequences of the backwater effect [43], assessment of the physical habitat suitability for fish [44], and many other works with a wide variety of themes.…”