The purpose of this dissertation is to explore the effects of climate change on Michigan’s grape industry from a historical, present-day and future perspective. The majority of the research concentrates on grapes grown on the western coast of Michigan, where the majority of grapes grown for wine purposes are produced. The impetus for this dissertation was the fact that in the 1960s, production of Vitis vinifera (sub varieties include Riesling, Cabernet Sauvignon, etc.) was non-existent yet by the decade of the 2000s, growth in terms of acreage was more than 300% and Michigan was expanding into a regional power for wine. Climate change, as is proved by this dissertation, was the main driver behind this shift. The dissertation begins by discussing the general concept of terroir, or “land characteristics,” which include an area’s soils, topography, culture and climate. Terroir is a central theme in grape and wine production, as it can vary immensely over even the smallest of scales. Of the four main characteristics of terroir, climate is the most variable of over time, and thus should be considered tomerit the most focus of the four characteristics when considering grapes and wine from an agricultural perspective. Other concepts including microclimates and scale are also discussed. The next chapters are composed of three papers written for publishing in scientific journals. The second chapter explores how climate change has impacted the grape industry in the past. Southwest Michigan’s growing season has warmed up by an average of 3.8 growing degree day (GDD) per year increase since 1980 and the growing season has grown by an average of 28.8 days since 1971. The third chapter looks at present day issues for the grape industry, particularly by looking at the importance of the early growing season (1 Mar – 20 May). It was found that the early season is of great importance to the potential success of any growing season and the issues such as the rate at which GDD accumulate and the occurrence of spring frosts are of significant concern. The fourth chapter used downscaled data from the CMIP5 suite of climate models to explore the potential impact of future climate change on Michigan’s grapes in southwest and northwest Michigan. Some of the primary obstacles to the production of vinifera in the 1960s (prior to its introduction) are likely to diminish in scale as climate change continues in the Great Lakes region. The dissertation concludes with a discussion chapter recapping the findings of the previous chapters. This discussion chapter also suggests the implications of the findings, which concern climate change and agriculture on a global scale. It is with some concern that a region like Michigan has been to shift to be able to reliably grow Vitis vinifera grapes in such a short amount of time, and questions regarding similar circumstances for other crops and other regions of the world are asked. Improvements for the studies and future research directions are also discussed.
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