Just in this last week, we here in Santa Barbara got another reminder of the risks associated with human-caused climate change. The national weather service announced another heat wave for July, and we braced for the sweat. While we can’t always distinguish the precise level of human contribution to a specific heat wave, the broad signals are too strong to ignore.
California is warmer, about 2 degrees more than the average from 1949-2005, with an increasing rate of heat waves. A good amount of that average temperature uptick is in night-time low temperatures, which aren’t as low as they used to be and make heat waves more difficult to deal with. The severity levels of the most recent droughts have increased, and more precipitation is coming down in the state as rain rather than snow, leaving less snowpack and creating additional stress on water supplies in the state.
I could go on and on about these problems, their physical basis, and other risks to our communities and the natural world. But most Californians understand at least the basics, and don’t need to be further convinced that humanity’s greenhouse-gas emissions are playing a large role.