The warm winter has left very little snow in California’s Sierra Nevada, and now an extreme heat wave is accelerating the rapid melt in the mountains. The Sierra snowpack measures 48% of average for this time of year, according to state data, down from 73% of average in late February. … California relies on the Sierra snowpack for about 30% of its water, on average. But the extraordinary warmth across the West this winter, which broke records in many areas, brought more precipitation falling as rain instead of snow. Scientific research has shown that human-caused climate change is pushing average snow lines higher in the mountains and changing the timing of runoff.

Other water supply and climate news:

• E&E News by Politico: EPA shifts program for water utilities to downplay climate change
• Inside Climate News: Summer in March? Unusual heat wave descends on already parched Western U.S.
• USA Today: A flower’s fight against extinction could be big climate change news
• Source NM: Opinion: The science on climate change is clear — so is the need for moral reckoning
• Invisible Waters: Blog: Heading toward a terrible peak snowpack