Impact of Severe Climate Conditions on Wine Production in Peninsular Spain

Spain is one of the world’s leading wine producers and is therefore particularly vulnerable to the impacts of climate change on this sector. This work assesses the impact of climate change on viticulture using bioclimatic indices specifically designed for grapevines. To this end, precipitation- and temperature-based indices were analyzed across the protected designations of Origin (PDOs) of Spain, computed from daily outputs at very high-resolution (5 km) regional climate simulations performed with the Weather Research and Forecasting (WRF) model (v4.3.3) for the Iberian Peninsula. Specifically, two simulations were conducted, including a 30-year simulation representing a recent past period, with WRF driven by ERA5. A second 30-year simulation representing severe climate change conditions was also performed, with WRF forced with ERA5 combined with a mean climate change signal derived from a CMIP6 multi-model ensemble under the SSP5-8.5 scenario, using the pseudoglobal warming (PGW) approach. The simulated indices were previously evaluated against those computed from the gridded observational ROCIO_IBEB product, developed by the Spanish Meteorological Agency (AEMET).

Overall, the evaluation showed that WRF has good skill in representing the main spatiotemporal characteristics of wine-related bioclimatic indices. Concerning potential changes under severe climate change conditions, PGW results suggest a northward and northwestward shift of optimal climatic conditions for vineyards, while PDOs in the southern plateau and along the Mediterranean coast show a decline in climatic suitability for wine production. These changes are driven by a general increase in temperatures, including warmer nights during the ripening period, and an extension of the growing season in northern PDO regions. Moreover, southern and coastal PDOs are expected to experience a marked increase in extremely hot days, which could negatively affect grape yield and quality. Additionally, a substantial reduction in precipitation and a trend toward drier conditions are projected, leading to a decrease in areas with optimal moisture availability and an expansion of regions under water stress.

These findings may provide a robust basis for designing adaptation strategies to climate change in the viticultural sector.

Acknowledgements: This research has been carried out within the framework of project PID2021-126401OB-I00, funded by MICIU/AEI/10.13039/501100011033 and by ERDF, EU.