Multi-Scale Analysis of Climate Change: Case Study of Major Canadian Wine Areas

Abstract

The release of anthropogenic greenhouse gases (primarily CO2) is estimated to have caused an average increase of 1.2 ℃ in global warming since pre-industrial times (1850–1900) and is projected to continue its rise based on Global Climate Models. This study uses Regional Climate Models to evaluate the effects of climate change on three well-known wine regions in Canada: the Niagara Region, the Annapolis Valley, and the Okanagan Valley. Nineteen models were evaluated against historical trends from 1950 to 2021 to find the most accurate and precise model for each region. Using model data, two types of climate indices, Climate Suitability and Climate Risks, with a total of ten parameters, were used to assess the impacts of climate change on the wine and grape industry. All of these are important for winegrowers with more focus put on the number of heat (GS-HD), frost (GS-FD), and growing degree days (GDD). Under the business-as-usual scenario (GHG emissions, RCP 8.5) from 2020 to 2100, the Niagara Region, Annapolis Valley, and Okanagan Valley will likely experience increases in GS-HD of 30, 23, and 55, respectively. Additional impacts arise from the change in the number of GDD increasing by 764, 980, and 912 in respective regions. Thus, all three regions will move into a “hot” climate based on the Winkler Index. When we, as a society, are successful in mitigating CO2 emissions to an RCP 4.5 scenario, then GS-FD are predicted to decrease between 2020 and 2100 by just 10, 11, and 35 in Niagara, Annapolis, and Okanagan, respectively. During the same period, the GDD will increase by 465, 306, and 443, allowing them to grow more varieties of grapevine that thrive under a warmer climate. Overall, each locality will reap more benefits from increasing temperatures under the RCP 4.5 scenario than the RCP 8.5 one. It is regional-scale studies of Climate Change, employing Regional Climate Models, that the wine industry needs to make sustainable decisions appropriate to the local level, whether they are established or emerging wine growing regions. Finally, location-specific Regional Climate Models may be invaluable instruments in aiding/sustaining the agricultural industry.