SAN DIEGO — Political leaders around San Diego will have to prepare for multiple climate change impacts in the future, beyond the expected rising sea levels, a professor at the Scripps Institution of Oceanography told members of the San Diego City Council’s Natural Resources and Culture Committee.
Among the impacts outlined by Professor Ralph Keeling Wednesday were a higher demand for water due to warmer temperatures, a mountain snowpack that melts faster, greater numbers of wildfires and migration of animal species.
He said that because a warmer atmosphere can hold more moisture, the region is likely to see both increased drought and more intense storms.
“One of the things we don’t know with great certainty from models is what the warming will do to precipitation,” Keeling said. “Some models say it will be wetter and some models say it would be drier — that’s in terms of the number of centimeters or inches of rainfall per year.”
No matter which way it goes, warmer temperatures will increase demand for water, he said.
Officials across San Diego County are working toward diversifying San Diego’s water supply. Among the efforts are increasing the use of recycled water in the city of San Diego, the expansion of the San Vicente Reservoir near Lakeside and construction of a large desalination plant in Carlsbad.
Most of San Diego’s water is imported from Northern California and the Colorado River, with only a small portion produced by local rainfall.
“The one thing that’s quite clear is that there’s going to be less snow and there’s going to be less snowpack,” Keeling said. “So we depend, in part, on our water supply by the Sierra Nevada Mountains continuing to melt their snow through the summer — so the late summer water supply is going to be an increasing issue.”
He said the lowered summer water supply will also affect the ability to create hydroelectric power.
The professor said every 1 degree centigrade increase in temperatures is expected to cause three times more wildfires and six times more acreage burned. Also, politicians will have to create plans for open space that will allow species to migrate from one place to another as they seek to survive in changing climactic conditions, he said.
According to Keeling, the effects of climate change will grow over decades and continue well into the next century.
The city is also developing a “Climate Action Plan,” which is designed to help San Diego reach state-mandated goals for the reduction of greenhouse gas emissions by 2020 and 2035.
Nicole Capretz, who sits on a task force that’s overseeing the plan, said Mayor Bob Filner has toughened some of the proposed targets, which will be revealed at a meeting to be scheduled in September.
The plan could be presented to the City Council committee this fall.