Climate change threatens California’s future

California faces a twofold climate challenge: finding cost-effective ways to reduce emissions of greenhouse gases (GHGs) and preparing for the changes that are expected even if global emissions fall. Greenhouse gas emissions pose a serious threat. The state experienced 7 of its 10 warmest years on record from 2012 to 2018, and warming is expected to continue. Sea level is predicted to rise 2 to 7 feet on California’s coast by 2100, and the frequency of extreme events such as droughts, heat waves, wildfires, and floods is expected to increase. Higher temperatures result in more precipitation falling as rain (and less as snow), which will increase both the frequency and magnitude of flooding and diminish water reserves in the Sierra snowpack.