Irrigation Distribution Networks’ Vulnerability to Climate Change

Abstract

Climate change will lead to changed demands on existing irrigation systems. This paper presents a methodology for investigating the performance of irrigation networks under climate change, and applies this to an irrigation network in Cordoba, southern Spain. The methodology uses emission scenarios (A2 and B2) developed by the Intergovernmental Panel on Climate Change. A global climate model (HadCM3) is used with downscaling to predict climate variables for 2050 and 2080 under the emission scenarios. European agricultural policy scenarios are used to predict future cropping patterns. Irrigation water requirements are then estimated for various combinations of these climate and cropping pattern scenarios, and the performance of the irrigation network is evaluated in terms of the equity and adequacy of pressure at the outlets, using EPANET. The methodology was applied to the Fuente Palmera irrigation district, which supplies water on-demand for drip irrigation. The results show that climate change would have a major impact on network performance with the existing cropping pattern, but that expected changes in cropping pattern would reduce this impact.