Climate-change reality check in California

Data on Lake Tahoe and wilderness fires remind that global warming is very real. And now.

The California Environmental Protection Agency's report can be read at The UC Davis report on Lake Tahoe is available at

This month has—so far—brought two disturbing new reports on the effects of climate change on California.

First, the 2013 “State of the Lake Report” on Lake Tahoe, from the UC Davis Tahoe Environmental Research Center, did have a ray of good news: Clarity has improved for the second year in a row, no small thanks to the efforts of environmentalists.

But the bad news is that one of the factors in a clearer lake is lower precipitation and less runoff, as well as less “deep mixing” in the winter—when colder water sinks, bringing nutrients (algae, food) to the surface and clouding the water.

Last year, the lake’s average temperature of almost 53 degrees was the highest on record.

And that brings us to more bad news: The California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment released an update to its 2009 report “Indicators of Climate Change in California.” In 240 pages, the agency provided evidence that the warming trend is continuing with significant changes in every part of the state. The lakes are warmer, the average temperatures—even when extremes are accounted for—are hotter, and wildfires are trending upward in both frequency and intensity.

Just since 2000, California wildfires have burned twice the acreage that was destroyed in all fires between 1950 and 1999, as the report points out.

We’re now heading toward the peak of what’s already been a dangerous and deadly fire season, and as the science in these reports make clear, the trends are continuing. While the good news in the OEHHA report is that California businesses and residents are making greater efforts to decrease their carbon output, we’ve still got a lot of work to do—including preparing to live in a California that is very different from the one we have today.