Photo illustration depicts potential flooding of Sacramento's Arco Arena and Natomas community. Photo courtesy of California Department of Water Resources.
Scripps Institution of Oceanography researchers say if climate change trends continue, flood magnitude will increase 50 to 100 percent in the southern Sierra Nevada by 2100, affecting California's water supply.
The state's reservoir system provides both water storage and flood protection. Study lead author Tapash Das, a visiting research hydrologist at Scripps, said more severe floods would require maintaining reserve levels in key reservoirs, meaning that valuable water might have to be released.
During a period when California is expected to experience warmer temperatures and dryer weather, flooding could still increase, especially in winter months. Hydrologic models showed that combined with storm intensity, warmer mountain temperatures could increase runoff, and more rain would hasten the melting of existing snow.
So, despite climate models showing a decrease in the average amount of rain and snowfall in California, when the wet stuff does come, it's expected to fall mostly as rain, delivered in intense storms.