California Farmers Must Face Climate Change

by | May 20, 2014

By Edward Ortiz

Dire consequences face the state's powerhouse agricultural industry if it does not take steps to adapt to climate change, said a panel of 14 scientists, as well as Gov. Jerry Brown, at a conference on climate change Monday in Sacramento.

The conference brought together economists, analysts, scientists and policymakers from the University of California and state government at the California Museum downtown.

Members of the agricultural industry also attended. The conference sought to underscore that a troubling brew of warmer nighttime temperatures, drying soils, shrinking snowpack and drought must be addressed by farmers and society at large.

Brown said Californians need to be able to support a series of moves over a long period of time because of climate change effects. "This is something that has yet to fully capture the public imagination," Brown said. "There is still great denial."

There was no such denial among scientists at the gathering, which was sponsored by the Giannini Foundation of Agricultural Economics at the University of California. Experts who spoke accepted climate change as inevitable, but focused on the need to adapt. Farmers might have to change the type of crops they plant and when they are planted, they said. Some might go out of business.

"The expected temperature changes for the global mean are for (between) 4.5 and 8.5 degrees by 2100," said Benjamin Santer, an atmospheric scientist from Lawrence Livermore National Laboratory. "That's a very different world.

"California would be profoundly impacted by that."

Santer was quoting from scientific projections from the recently released fifth report by the Intergovernmental Panel on Climate Change, a body of several hundred scientists whose findings are widely considered authoritative.

Maximillian Auffhammer, a professor of environmental economics at UC Berkeley, called the effects of climate change a "slow-moving process" that offers the agricultural industry a window of opportunity in dealing with climatic uncertainties.

"There are some sectors that are sensitive to climate change and some that aren't -- and agriculture, of course, is one of them," Auffhammer said.

Auffhammer said climate change will bring more extreme heat events -- summertime periods of unusually high temperatures -- to California, and some crops will be damaged more than others.

"There are a lot of high-value crops that have very specific requirements in terms of nighttime temperatures and dew points (the temperature at which water vapor in cooling air starts to condense)," Auffhammer said. "If weather changes in a way that is not favorable to these things in the ground, then you're putting huge assets at risk."

Scientists at the conference said that so far there has been no change in daytime temperatures or average daytime highs in the state, but the nighttime low temperature in both summer and winter has risen.

"What happens in Napa Valley if that nice fog that rolls in goes away and moves 30 miles to the north and you have a degree change on average at nighttime?" said Aufhammer. "These grapes ... are incredibly sensitive to these small dimensions of weather."

He said a small rise in temperatures at night could put the state's whole wine industry at risk.

Auffhammer also said that rising temperatures will have measurable impacts on farm worker productivity. "Hot temperatures lead to lower economic output in measurable terms of gross domestic product, and one of the most affected by hot temperatures is the agricultural sector."

Some scientists drove home the point that climate change issues need to be taken in a global context, since weather and economic factors are deeply interconnected.

"What you need to worry about is if climate change in China is such that almonds becomes an ideal crop for them -that's the big regime change," said Daniel Sumner, a resource economist at UC Davis. "We can't get too wrapped up in what the climate is doing here. It's important to think about this in a market context, and that means a global context."

Sumner said warmer winters already have resulted in higher winter wheat production in Yolo County.

He said that, in simple terms, climate change may mean shifting weather patterns. Yolo County, for instance, could come to resemble Stanislaus County in terms of temperature patterns for growing crops.

(c)2014 The Sacramento Bee