Climate change and its consequences for viticulture

Abstract Climate change has been occurring for the past several decades because of changing atmospheric concentrations of greenhouse gases, and alteration of the earth’s surface through deforestation, desertification, and urbanization. The role of climate change is substantial across all agricultural crops and is particularly noticeable for specialty crops such as winegrapes. Specific climatic effects have included increased heavy rainfall across many regions globally, more frequent heatwaves, and less frequent extreme cold temperatures and cold waves. Additional impacts have been seen in the incidence of large fires in western United States, Australia, and Portugal, which have affected grape growing and wine production in some regions. An example of this impact is an increased frequency in smoke-tainted wines in western United States and Canada as well as Australia. Many mountainous regions have experienced annual trends toward earlier spring melt and reduced snowpack, which affect water resources for agriculture, and consequently, increased frequencies in droughts have been observed. A significant physiological result of climate change is also the decoupling of grape maturity based on soluble solids and maturity based upon secondary metabolites such as anthocyanins, phenols, and aroma constituents. Specific cultural practices may need to be implemented to delay fruit maturity or otherwise mitigate this uncoupling phenomenon. Positive implications of global climate change include the emergence and development of new wine industries in northern Europe (e.g., England, Sweden, Denmark, Poland).