Climate change in California passes a tipping point

[F]or the first time in 120 years of record keeping, the winter average minimum temperature in the Sierra Nevada was above freezing. And across the state, the last 12 months were the warmest on record. This explains why the Sierra Nevada snow pack that provides nearly 30% of the state's water stood at its lowest level in at least 500 years this last winter despite precipitation levels that, while low, still came in above recent record lows.