Wendy Zhong is a Sacramento Valley College Corp Fellow with Cool Davis and a third-year undergraduate student majoring in Food Science at UC Davis. Wendy is from Oakland, California, where she developed a sense of ceativity, compassion, and optimism. Wendy plans on continuing her studies in graduate school.  She is pictured in this article. 

Climate change has emerged as an obvious global issue in recent decades, significantly impacting people in a variety of ways. Its broad impacts disturb ecosystems and alter weather patterns, and it has an immediate effect on essential resources such as food and water. Rising temperatures, irregular weather patterns, and shifting precipitation patterns all have an effect on the availability and quality of essential resources, increasing the issues faced by communities throughout the world and here in Yolo County. This challenging issue requires urgent attention and solutions since it not only threatens global food security but also threatens the accessibility and sustainability of clean water supplies, endangering the well-being of individuals and whole communities.

Impacts of droughts, floods, and heatwaves

The complicated relationship between climate change and the availability of food and water resources presents multiple issues. Changes in temperature and precipitation patterns have significant effects on agricultural production, affecting crop yields and livestock. Droughts, floods, and heatwaves are becoming more frequent and severe, causing widespread crop failures. These changes increase the risk of individuals who are vulnerable, limiting their access to get sufficient food and safe drinking water. At the same time, freshwater supplies are under greater pressure as a result of changing weather patterns, increasing shortages and pollution concerns and expanding the responsibility of supplying the increasing global need for clean water.

Climate change’s impact on food supplies is varied, generating disruptions throughout agricultural cycles. Temperature and rainfall patterns disturb these cycles, resulting in lower agricultural production and decreased livestock health. Floods and droughts, as well as storms, wreak damage on crops, infrastructure, and fertile soil, further reducing agricultural production. Climate change also contributes to the spread of pests and illnesses, affecting both plant and animal-based food production systems. This results in food shortages, inflation, and nutritional deficiencies, disproportionately affecting disadvantaged groups throughout the world.

Similarly, the consequences for water resources are serious, as changing precipitation patterns and increased evaporation rates strain freshwater supplies, causing shortages and endangering their quality. Glacial melting and sea-level rise endanger freshwater reserves by polluting existing sources and increasing the hazards of waterborne illnesses and shortages in many areas.

Yolo County impacts to farmers and crops

When asked about her thoughts on climate change in agriculture, Denise Sagara, Executive Director of the Yolo County Farm Bureau, noted that “The weather is always changing, from the recent severe drought to the current two years of quite a lot of rain.” Regarding water reliability and strategies to improve water use efficiency and crop resilience to drought, Sagara stated that most crops are now being irrigated using drip or micro-sprinklers for water efficiency. For crop resilience, she mentioned that “due to research crops are always being improved for optimum production results.”

On the threat of new pests as temperatures rise, Sagara emphasized the importance of preventative monitoring and mitigation efforts. She said, “Pests can be a major problem. Growers know to watch for outbreaks in their crops. Most fields are monitored daily for growing conditions including the need for irrigation, pest control, etc. It’s very important to treat pests as soon as they are found before they become a major problem.”

When asked about adaptive farming techniques or advanced technologies that could be game changers for agriculture in Yolo County, Sagara responded, “As new ideas are introduced growers review them to see if they can be adopted to the crops they farm. Many have gone to no-till or low-till when it fits in the crop rotation.” Regarding the 14.5 percent decline in total gross production value for 2022 compared to 2021 across Yolo County, Sagara attributed it primarily to water shortage and adverse conditions, stating, “Almonds and grapes [were] hit by freeze and walnuts were sunburned just before harvest, affecting both quality and quantity. Many orchards of walnuts and some almonds are being removed, so production likely fell again in 2023.”

She provided specific details on the impact on various commodities:

  • Almonds: Acreage reduced from 38,300 to 19,200 with a reduction of income of $76,000,000.
  • Walnuts: Prices dropped drastically and income went from $37,000,000 to $15,000,000.
  • Rice: Acreage dropped from 15,000 acres to 8,000 acres, and production from 68,900 tons to 27,000 tons. Even with the price increase in 2022, the reduction in gross income was $18,000,000.

Higher temperatures also mean fewer chill hours

Yolo County, as an agricultural powerhouse, is particularly vulnerable to climate shifts that threaten crop growth. The rising minimum winter temperatures have resulted in a decrease in necessary chill hours required for tree nut blooming and fruit production, potentially resulting in decreased yields for crops such as walnuts over time. Because of shorter winter growing seasons, this warming trend may have an impact on cool-season crops like wheat, but it could additionally promote the growth of heat-tolerant crops including tomatoes, rice, and alfalfa.

Moreover, Yolo County’s models foresee distinct impacts on various crops resulting from escalating minimum temperatures and dwindling chill hours. While rice, tomatoes, and alfalfa may increase, the decrease in winter chill hours could substantially reduce walnut yields. Yolo study author Hyunok Lee highlighted the faster rise in lower temperatures during winter months, potentially leading to a decline in walnut acreage. Although farmers might think about switching varieties, UC Davis researcher Daniel Sumner stressed the importance of market factors in such decisions.

Solutions: Storage, improved irrigation, and modeling

Since California contributes over half of the nation’s vegetables and fruits/nuts, climate change disruptions represent a significant danger to national food security. Researcher Ellen Bruno emphasized the necessity of proactive management strategies for Yolo County’s ongoing success as an agricultural powerhouse. Strengthening storage facilities, improving irrigation methods, dedicating resources to crop breeding, and utilizing predictive modeling stand out as essential steps to alleviate the increasing effects of these challenges.

Furthermore, as an agricultural powerhouse dealing with the effects of climate change, Yolo County is at the forefront of risk management. By 2050, a customized study predicts potential improvements in alfalfa results but little impact on rice, tomatoes, and wine grape companies. However, new pests enabled by higher temperatures form a looming threat. Monitoring for pests such as stem nematodes and taking precautions against outbreaks similar to previous soybean rust epidemics becomes essential.

Water reliability has become a top concern, the growing unpredictability due to shifting snowmelt and rainfall patterns. Efforts are in progress to strengthen Yolo County’s floodplains specifically for winter storm groundwater recharge, aiming to boost reserves for summer irrigation. However, the reduced availability of water during summertime might mean having to leave 10-15 percent of lower-value field crops unattended. Investing in pressurized irrigation systems can significantly improve how we use water.

Conclusion

Based on historical data and statistical predictions, it’s becoming increasingly clear that climate change is already impacting the crops grown in Yolo County. These forecasts suggest that this trend will persist, highlighting the unpredictability surrounding the availability and quality of water resources. Despite this understanding, there’s uncertainty about how future changes in prices, technologies, and water availability will unfold due to alterations in statewide snowpack and other non-climate-related factors influencing crop decisions.

The relationship between climate change, agriculture, and water resources in Yolo County underscores the urgency for innovative and adaptive strategies such as implementing shade protection, optimizing water usage and mitigating heat stress and adopting advanced technology, such as drones, for early pest detection. As we navigate these challenges, exploring further insights from organizations like the Yolo County Agriculture Department could offer deeper understanding and potential solutions. For those interested in delving into this critical nexus, reports from the California Department of Food and Agriculture or research papers from the UC Cooperative Extension provide valuable insights. Engaging with local initiatives, such as water conservation programs or climate resilience projects, can empower communities to take actionable steps toward mitigating these impacts.

A special thank you to Denise Sagara, Executive Director of the Yolo County Farm Bureau, for her time and expertise!

Resources

Yolo County Agriculture Department’s official website (https://www.yolocounty.org/government/general-government-departments/agriculture-cooperative-extension/agriculture-and-weights-measures)

Yolo County crop statistics

https://www.yolocounty.org/government/general-government-departments/agriculture-cooperative-extension/agriculture-and-weights-measures/crop-statistics

Kan-Rice, P. (2016, March 22). How is climate change affecting agriculture?. University of California.https://www.universityofcalifornia.edu/news/how-climate-change-affecting-agriculture#:~:text=In%20Yolo%20County%2C%20warmer%20winters,which%20require%20more%20chill%20hours.

Jackson, L., Haden, V.R., Hollander, A.D., Lee, H., Lubell, M., Mehta, V.K., O’Geen, T., Niles, M.T., Perlman, J., Purkey, D., Salas, W., Sumner, D., Tomuta, M., Dempsey, M., Wheeler., S.M (2012) Agricultural mitigation and adaptation to climate change in Yolo County, CA. California Energy Commission Project 500-09-009, pp.153.https://scholarworks.uvm.edu/calsfac/2/

Pathak TB, Maskey ML, Dahlberg JA, Kearns F, Bali KM, Zaccaria D. Climate Change Trends and Impacts on California Agriculture: A Detailed Review. Agronomy. 2018; 8(3):25. https://doi.org/10.3390/agronomy8030025