to support multiple-use management and conservation across large parts of the region.”
Indeed, the region has regularly known some stretches of dry condi- tions. Short-term droughts com- monly occur in California, but only two droughts have lasted for more than four years in Northern California since record-keeping began in 1850. The fi rst occurred between 1929 and 1934 and the second, 1987 to 1992, is considered the most severe drought in the state’s history.
The prospect of a reduced Sierra snowpack has prompted the Los Angeles Department of Water and Power (LADWP) to build the world’s largest groundwater treatment center to boost its local supply of drinking water. The utility plans to invest as much as $800 million to restore groundwater pumping of drinking water from San Fernando Valley wells that had been closed because of contamination. “By 2035, we plan to reduce our purchases of imported water by half,” said James McDaniel, senior assistant general manager.
Then there is the potential impact of climate change on the state’s $43 billion agricultural industry. “Crops that are not water-effi cient, such as rice and cotton, are very likely to be replaced with more water-effi cient crops,” according to Bales and Miller. Many Central Valley specialty crops, “which are the foundation of the agricultural economy,” are especially vulnerable to higher nighttime tem- peratures, they said.
Shifting patterns of agricultural
production in response to climate change “have received little atten- tion as a potential impact pathway for ecosystems,” according to “Climate Change, Wine, and Conservation,” a report on wine production and climate change published in April in the Proceedings of the National Academy of Sciences. Wine grape production provides
a good test case for measuring indirect impacts mediated by changes in agricul- ture, “because viticulture is sensitive to climate and is concentrated in Mediter- ranean climate regions that are global biodiversity hotspots,” the report said.
Farmers have been traditionally resilient to weather extremes, but the advent of climate change puts an added emphasis on the need to augment the existing storage regime, said Chris Scheuring, managing counsel for natu- ral resources and the environment with the California Farm Bureau Federation. “Aside from the possibility of rising temperature, it seems to me the most important event we can plan forward on is changing hydrology,” he said. “Just to stay even in the terms of water supply in the context of climate change I think we have to think very seriously about some of these new surface storage projects.”
This issue of Western Water looks at climate change through the lens of some of the latest scientifi c research and responses from experts regarding mitigation and adaptation.
A More Certain Variability Speaking to an irrigation conference in Los Angeles more than a century ago, John Wesley Powell, the famed explorer of the Grand Canyon and second director of the USGS, sounded
See the potential impacts of climate change in Los Angeles
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