Impact of Early Season Temperatures in a Climate-Changed Atmosphere for Michigan: A Cool-Climate Viticultural Region

This study assesses the impacts of observed (2001–2012) and projected climate change on early season heat accumulation for grape production (viticulture) in a cool-climate region of the world (Michigan, USA). Observational data were generated from a weather station located in the center of one of the most important appellations located in the SW part of the state. Climate change projections retrieved from a high spatiotemporal weather model using atmospheric conditions simulated for the end of the 21st Century. All the temperature variables considered demonstrated significant warming trends especially during the months of March, April and May. Temperature differences, increases in heat accumulation, and changes to potential frost events would necessitate new approaches to vineyard management. In fact, it is likely that vine budburst will occur earlier and early season frost develop as a new challenge. However, our study results are comparable with other viticulture regions of the world, with a warming trend of at least 3 to 5◦C in the months leading up to the growing season by the end of the 21st Century. Therefore, effective climate change adaptations will be important to the grape and wine industry in this region. Management strategies are needed to minimize climate risks while taking advantage of new opportunities related to improved climatic conditions for growing more late-ripening European Vitis vinifera grape varieties, relevant for producing higher quality wines.