Effort and Performance of the Management of Water for Agriculture under Climate Change in Southern Europe？

We evaluate alternatives for the management of water for agriculture under climate change in six representative basins of Southern Europe: Duero-Douro, Ebro, Guadalquivir, Po, Maritsa-Evros, and Struma. Management objective is the maximization of water availability, understood as the maximum demand that can be satisfied with a given reliability. We focus on water availability for agriculture. For the sake of simplicity, we assume only two types of demands: urban and irrigation. Water is first allocated to urban demands following an established priority; the remaining resources are allocated to agriculture. If water availability does not satisfy all irrigation demands, management measures are applied with the goal of achieving a balance between resources and demands. We present an analysis of three possible management measures to face water scarcity in a long-term scenario: increasing reservoir storage, improving efficiency of urban water use and modifying water allocation to environmental flows. These management measures are globally evaluated for the selected basins in three representative climate scenarios, comparing their possible range and effectiveness. Although such measures can significantly increase water availability and counterbalance a portion of water scarcity due to climate change in some basins like Ebro or Struma, in other basins, such as Guadalquivir, water availability cannot be enhanced with management measures and irrigation water use must be reduced