Bioclimatic Zoning of Future Viticulture Suitability in the Iberian Peninsula under Climate Change

Viticulture is driven by climate, which governs grapevine phenology, water balance, yield, and grape quality. Ongoing climate change is expected to disrupt the historical climatic suitability of established wine regions while enabling expansion into new areas. This study presents a bioclimatic zoning approach to identify preferential future areas for grape growing across the Iberian Peninsula.

High-resolution climate data from CHELSA (30 arc-seconds, ~1 km) were used for the historical period 1981–2010 and the future period 2041–2070, under SSP1-2.6, SSP3-7.0, and SSP5-8.5 scenarios. Traditional viticulture-related bioclimatic indices were calculated, including mean annual temperature, growing season temperature, the Winkler Index, annual precipitation, and the dryness index.

Historical vineyard conditions were characterised using Protected Designation of Origin (PDO) regions, which were used to define the reference climatic envelope for grape growing. For each index, threshold ranges were established based on values observed in PDO vineyard areas. Future regions were classified as preferential only when all selected indices simultaneously fell within the defined thresholds, ensuring a conservative suitability assessment.

For the historical period, around 80% of the Iberian Peninsula exhibited preferential conditions for viticulture. Future projections indicate a precipitation decrease ranging from −20 to −50 mm/year and temperature increases between 1.6 and 2.6 °C. These changes, as reflected in the bioclimatic indices, lead to a reduction in preferential areas, particularly in southern and interior regions, driven by increasing temperatures and greater aridity. Coastal and higher-elevation areas show greater persistence of suitable conditions, while some expansion potential is observed in northern regions. The preferential area for viticulture in the Iberian Peninsula is projected to decline to between 34% (SSP5-8.5) and 50% (SSP1-2.6).

The framework provides a basis for climate-informed site selection, regional planning, and targeted adaptation strategies for viticulture in the Iberian Peninsula under future climate change.