Impact of climate change on wine production: a global overview and regional assessment in the Douro Valley of Portugal

This paper examines the nature of climate change, viticulture and wine at the global scale and details changes and projections in the historic Douro wine region of Portugal. Overall, the observed warming over the last filly years in wine regions worldwide has benefited some by creating more suitable conditions, while others have been challenged by increased heat and water stress. The projected future warming at the global, continent and wine region scales will likely continue to have both beneficial and detrimental impacts by opening up new areas with increasing viability to viticulture, or by severely challenging the ability to adequately grow grapes and produce quality wine. Observations from the Douro region reveal higher growing season temperatures, increases in extreme temperatures, fewer cold events that are not as cold as before, more and higher heat stress events and a lower diurnal temperature range. Projections indicate that further warming may range from 0.8-6.6 degrees C by 2020 to 2080, while precipitation during the growing season is projected to decline by up to 7-22% over the same time period. Continued research and understanding is needed to decrease vulnerability and enhance the adaptive capacity of both the Douro and the global wine industries.