By Kevin Hecteman
As the 21st century continues, Southern California will likely feel the effects of climate change, and farmers and ranchers will want to be ready to adapt: That’s the main conclusion of a report released by the California Department of Food and Agriculture, which partnered on the project with the San Diego-based Climate Science Alliance.
At a webinar held recently, CDFA and the Climate Science Alliance discussed the findings and the need to tailor the report’s large-scale findings to local needs.
“Farmers are at the forefront of all of these extremes,” Connor Magee of the Climate Science Alliance said during the webinar. “We’ve heard that in our feedback. A lot of the challenges that are faced (in) climate change, farmers experience firsthand on a daily basis.”
One theme Magee said he’d heard repeatedly in the course of his work was the need for cooperation among farmers—”a stronger connection to the researchers and technical-assistance specialists … knowing where to go and having support when new challenges arise.”
The report examines the observed and anticipated changes in several regions crucial to California agriculture: the southern San Joaquin Valley, the Imperial and Coachella valleys, and San Diego County.
In the southern San Joaquin Valley—defined in the report as Kern, Kings and Tulare counties—the report forecasts increases in average summer and winter temperatures of anywhere from 7 to 11 degrees by 2100, while annual precipitation may decline by as much as 3.5 inches in lower elevations and as much as 10 inches in higher elevations, along with a 9-inch decrease in the snowpack.
Almonds, the second-most-valuable crop in Kern County behind table grapes, could see higher yields from warmer springs and summers, the report said, but could also see a shorter bloom season in January and February due to warmer temperatures. Declines in seasonal fog may cut into the chill hours needed for tree development.
The inland desert, mainly the winter vegetable-growing region of Imperial and Riverside counties, could see more intense heat waves and precipitation, carrying a higher risk of flash flooding.
San Diego County, the state’s top avocado producer, could see more intense extreme-precipitation events and greater warming inland compared to the coast, the report said.
Avocados, according to the report summary, could be in for as much as a 45% reduction in yields statewide. Future production may shift from coastal and inland Southern California to coastal Central California as the southern half of the state warms. The report said water availability could become an issue, resulting from lower precipitation and the threat of droughts.
The summary also calls for more research into nursery and cut flower production, to help understand how climate change will affect them, “while helping to inform opportunities for innovation, resource efficiency, and best-management practices that ensure production flourishes in the future.”
The report and the summary of crop impacts may be found at www.climatesciencealliance.org/2020-consortium.