Lake Tahoe warmer, dirtier - scientists worry

Lake Tahoe, the jewel of the Sierra once so crystal-clear that Mark Twain likened boating on it to floating on air, is warmer and soupier than ever before as a result of climate change and human activities, UC Davis scientists reported Wednesday.

Their 45-page report, the most comprehensive ever done on the lake, outlines significant changes in weather patterns over the years, including less snowfall and more rain, deteriorating lake clarity and increasing water temperature in the Lake Tahoe Basin - all of which could increase invasions of exotic fish and plant species.

"Change is a difficult thing, and the lake is changing," said Geoff Schladow, director of the UC Davis Tahoe Environmental Research Center and co-editor of the report. "But I think it is too early to say that our efforts are in vain. We can't judge each year in isolation. It's not all doom and gloom."

But there is reason to be concerned about the second-deepest lake in the United States, researchers said. Conditions appear to be getting worse, even as environmental and planning agencies work to reduce runoff from residential and commercial development and improve water quality in the lake.
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