It might be appropriate that California water managers designate April 1 as the date when the Sierra snowpack is presumed to be at its peak for the season.
It tends to be unpredictable.
But this year’s bounty is no April Fool.
The water content of the Sierra Nevada snowpack currently stands at 164 percent of normal for this date (the official April 1 snow survey being held on March 30 this year, fudging for the weekend).
Two years ago, it stood at 5 percent.
The difference is starkly illustrated in satellite imagery that KQED has compiled from Planet Labs, comparing three well-known parts of the Sierra this year, side-by-side with the same spots in 2015.
NASA snow hydrologist Tom Painter says it was like taking the entire average annual flow of the Colorado River and dumping it on the Sierra in about six weeks’ time.
“Our best outlooks using climate models suggest [that] as we continue to put more greenhouse gases in the atmosphere, we’re going to see, on average, warmer winter temperatures.” Bales says the evidence is already on the ground, the “snow line” (elevation where it becomes cold enough for rain to turn to snow) having moved uphill “a few hundred feet” in recent decades.
Jan. 2015 Jan. 2017 JuxtaposeJS “We’re getting more of those warm storms where the snow line is up 8,000 or 9,000 feet in the mountains.” For the record, that 1983 snowpack was at 230 percent—more than double—the “normal” amount around April 1.
By almost any measure, however, this has been a banner year.