Grapegrower Perceptions of Climate Change Impacts and Adaptive Capacity in Southern California

Background and goals Southern California, an important producer of high- quality wines, continues to expand its grapegrowing areas, supporting livelihoods and contributing to thriving local economies. However, climate data indicate that the region is becoming increasingly warmer and drier, threatening future winegrape production. Grower perceptions of climate change and their vineyard management responses play a critical role in adaptive capacity but have not been well examined for this region. Methods and key findings We used a survey to examine how grapegrowers in the South Coast American Viticultural Area perceive climate and climate impacts, as well as their adaptive capacity. Based on 71 responses, we found that growers have been observing fewer rain events (73%), more frequent heat events (63%), and earlier budbreak (32%) and harvest dates (41%) over the past decade. Growers reported implementing a variety of shortterm adaptive practices such as canopy management, but fewer considered long-term anticipatory measures such as planting drought and heat tolerant varieties. Based on a logistic regression model, growers who showed greater concern about future climate impacts were more likely to report implementing adaptive strategies on their vineyard in the last five years (odds ratio = 5.314, p = 0.017). Lastly, many growers feel they do not have the support (34%) or resources (52%) necessary to implement adaptive strategies. Conclusions and significance This survey revealed that growers in the region are experiencing a changing climate, some growers are already adapting to this change, and improved access to resources and support are critical for adaptive success. We identify a pressing need for collaboration and knowledge sharing between growers, academics, and local government agencies toward capacity building.