Agricultural Drought Indices - US Department of Agriculture

Monitoring Regional Drought Conditions in the Segura River Basin from
Remote Sensing
S.G. García Galiano 1 , M. Urrea Mallebrera 2 , A. Mérida Abril 2 ,
J.D. Giraldo Osorio 1 , C. Tetay Botía 1
1 Technical University of Cartagena, Research Group of Water Resources Management
2 Confederación Hidrográfica del Segura, Murcia, Spain
Abstract
The Segura River basin, located in southeast Spain, is a territory that is becoming more and more
vulnerable to rainfall variability. This implies uncertainties in agricultural activities due to the
scarcity of water and the increase in droughts. Early detection and spatio-temporal
characterization of droughts, at a regional scale, could contribute to the development of strategies
to mitigate their impact. Methodologies of spatio-temporal analysis of agricultural drought events,
from indicators based on remote sensing and meteorological data are presented.
Introduction
Human activities and demographic, economic, and social processes exert pressures on water
resources (WWDR3 2009). These pressures are in turn affected by factors such as public policies
and climate change. According to the Intergovernmental Panel of Climate Change, in southeast
Spain, an intensification of the water cycle is expected, with an increase in extreme events. The
development of strategies to mitigate the impacts of climate change is fundamental in order to
build “adaptive capacity,” which is considered a necessary condition to design and implement
effective adaptation strategies. Adaptive capacity could be reached by increasing the knowledge
of potential climate risks in individual basins (EC 2009).
The Segura River Basin, located in the southeastern part of the Iberian Peninsula (Figure 1),
presents the lowest percentage of renewable water resources of all Spanish basins. It is highly
regulated and has a semiarid climate, and its main water demand is agriculture. As a result, the
development and application of methodologies that permit an evaluation of spatial patterns of
agricultural drought conditions would contribute to the development and evaluation of mitigation
measures. Recently, the Segura River Basin was selected as a Spanish pilot basin in the
framework of the European Group of Experts on Water Scarcity and Droughts, because of the
correct management of severe drought events in recent years.
Figure 1. Segura River Basin in the Iberian Peninsula.
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