Portuguese wine denominations of origin under changing climates

Climate variability has a great impact on wine production and quality. To assess weather variability and climatic conditions, this research examines high-resolution extreme indexes of daily temperature and precipitation over 50 protected wine denominations of origin (DOs)/sub-regions in mainland Portugal. This study highlights the variations of present and future climate conditions between DO/sub-regions, for a better understanding of the nature of climate change across diverse regions of the country.

The analysis is based on a high-resolution dataset over mainland Portugal and for a baseline period (1981–2010). Climate change projections are also assessed for two scenarios (RCP4.5 and RCP8.5) and using a 5-member climate model ensemble retrieved from EURO-CORDEX climate projections data over the future periods of 2041–2070 and 2071–2100. A quantile mapping technique was used to bias correct the outputs from general circulation model (GCM) and regional climate model (RCM) combination.

The results highlight the spatial variability of Portuguese wine sub-regions for the present and future conditions. This study also shows that for future periods (regardless of the scenario) the wine sector in Portugal will likely see important climate changes across most regions. Increases in mean temperatures for each region accompanied by increasing severe dryness are projected in future climates mainly in south-eastern Portugal and along the upper Douro Valley (Douro Superior) in north-eastern Portugal. These DO/sub-regions are projected to become much drier than currently so irrigation or the introduction of new varieties are likely adaptation measures to maintain the viability and sustainability of regional viticulture in future decades.

Acknowledgments: Soil recover for a healthy food and quality of life (SoilRec4+Health). Projeto cofinanciado pelo Fundo Europeu de Desenvolvimento Regional (FEDER) através do Programa Operacional Regional do Norte (NORTE-01-0145-FEDER-000083).