Climate Change and Irrigation Water: Should the North/South Hierarchy of Impacts on Agricultural Systems Be Reconsidered?[Changement climatique et eau d'irrigation : La hiérarchie Nord/Sud des impacts sur les systèmes agricoles doit-elle être reconsidérée ?]

Pressures on resources and climate change are likely to strongly impact the availability of water, which directly affects agricultural systems. To estimate these impacts, we develop a prospective approach combining an agricultural supply side economic model and a crop model. We extend previous work by incorporating water resource constraints and apply our model to a large part of the French agricultural sector under three climate scenarios over 2010–2010. Results indicate that, at a given water price, potential change in irrigation water demand would differ strongly according to the region concerned and the scenario applied. In France as a whole, irrigation increases in all scenarios, by 60% under the intermediate scenario, by 40% under the least extreme scenario, and by 20% under the toughest scenario. Differentiating the northern and southern regions, the relative increase is more pronounced in the north, while demand in the south significantly increases under the intermediate scenario and decreases under the toughest scenario. When considering autonomous adaptation of farming systems to climate change, agricultural income in northern regions is likely to be negatively affected to a greater extent than in southern regions.