Two Fresno State professors say climate change will make the San Joaquin River’s annual runoff show up earlier — as much as six weeks earlier in the next century.
And one other thing:There will be a “significant decrease in annual stream flow,” said geology professor C. John Suen, who co-authored a study on the upper San Joaquin. Suen’s co-author was associate hydrology professor Zhi Wang.
The study, published in Hydrology Research, is more confirmation of findings in previous climate change studies, and it is not a pretty picture.
As water engineers and researchers have been saying for years, California’s reservoirs are built built to capture a gradual runoff from melting snow. More than half the state’s summer water supply is frozen in the snowpack each year.
If the state see more rainfall and earlier snow runoff, there could be big problems protecting communities and farms from floods.
In the San Joaquin Valley, the shift could be damaging for the multibillion-dollar economic base of agriculture.
This is about the place where the discussion turns to building larger reservoirs — such as Temperance Flat on the San Joaquin — or changing the way water and land are used. I’ll leave those issues to commenters here.
But Suen and Wang give us more reason to have the conversation.
The Yosemite Conservancy’s startling web cam shot of Half Dome this morning told me winter had returned.
But the National Weather Service told me not to count on a wet February.
“I expect another extended dry (temperatures cool to near normal) pattern to set in for the next one to two weeks,” meteorologist Paul Iniguez in the NWS Hanford office.
He said his forecast is in line with the NOAA Climate Prediction Center, which says odds favor a drier than average spring. Iniguez said precipitation for California is below normal.
For those who follow this stuff, check out NOAA’s El Nino-La Nina discussion. El Nino is the warm water phenomenon in the Pacific Ocean, sometimes meaning California will be wet. La Nina, corresponding to cooler water, can mean drier, cooler winters here.
Unfortunately, the Pacific is neither Nino, nor Nina this year. It’s tougher to handicap the wet season when neither is present in the ocean.
There’s a riveting online article raising the scary possibility of more frequent megastorms like the siege that struck California in 1861-62.
The Scientific American article says the rain started on Christmas Eve 1861 and continued 43 days, turning the Central Valley into an inland sea 300 miles long and 20 miles wide.
It apparently was not just a freak, the article says. New studies suggest this kind of storm hits every two centuries.
So will climate change increase the frequency? Just raising the question causes anxiety, and you can understand why. The article’s description of the 1860s event is like a script for a disaster flick.
Scientific American said: “Downtown Sacramento was submerged under 10 feet of brown water filled with debris from countless mudslides on the region’s steep slopes. California’s legislature, unable to function, moved to San Francisco until Sacramento dried out — six months later. By then, the state was bankrupt.”
It’s worth a read.