Future Scenarios for Viticultural Suitability under Conditions of Global Climate Change in Extremadura, Southwestern Spain

Weather condition is the main factor affecting winegrape production. Therefore, it is necessary to study the expected consequences of climate change on vineyards to anticipate adaptation strategies. To analyse how viticulture in Extremadura, in southwestern Spain, could be affected by warming, four temperature-based indices describing the suitability for grape production were computed for a reference period (1971-2005) and three future periods (2006-2035, 2036-2065, and 2066-2095). Projections were computed using a set of 10 global climate model (GCM) and regional climate model (RCM) combinations under two representative concentration pathways (RCP) scenarios, RCP 4.5, and RCP 8.5. Results showed that most of the Extremaduran region will remain suitable for winegrape production during the period 2006-2035. Later, for the mid-century, 2036-2065, depending on the considered index and the scenario, between 65% and 92% of the total area of Extremadura will be too hot for viticulture; for the end of the century, 2066-2095, between 80% and 98% of the region will be too hot. However, under the RCP 4.5 scenario, a few zones could be suitable for winegrape production but will require the use of new varieties and techniques to resist heat and drought stress.