Frost damage in specialty crops: current concerns, future risks, and implications for water resources

Frost is an important environmental constraint to the production of high-value specialty crops in temperate climates such as California's Central Valley, with the capacity to cause severe crop damage and large economic losses. However, there is limited literature on how climate change may affect frost risk for these crops. Identifying the relationships between climate change and frost exposure can provide useful information in support of adaptation planning. Moreover, as irrigation is a common management strategy for mitigating damages during many frost events, changes in frost risk have implications for irrigation water demand. Focusing on almond orchards in California's Central Valley, we applied a multi-pronged approach to assess contemporary impacts and current concerns surrounding frost damages, and to quantify future risks and implications for agricultural water use. First, a retrospective analysis of crop loss data available from the USDA Risk Management Agency identified contemporary trends in frost damages. Concurrently, semi-structured interviews were conducted with farmers and farm advisors to better understand their perception on climate risks and concerns (including frost) and the types of scientific information that can help them adapt to such impacts. Finally, a crop-specific phenology model was used to quantify frost exposure and water needs for frost protection under projected climate changed conditions for the mid-21st century. This unique mixed methods approach can be broadly applied to other high-value specialty crops, other regions, and with respect to other climate risks to provide valuable information for adaptive land and water management planning in support of sustainable agricultural production under climate change.