A structure built in the gold rush is exposed by the drying of Folsom Lake.
The jet stream tracked far north of normal over the eastern Pacific for all of 2013 causing severe drought on the west coast. California suffered through a record dry year from downtown Los Angeles to Eureka. Reservoir water levels are dropping rapidly.
This image shows that the lower half of the atmosphere above the northeastern Pacific was much warmer and thicker than normal in 2013, blocking jet stream flow that would bring storms to California.
A dome of warmer than normal air and higher than normal pressure pushed west coast storms towards Alaska.
The anomalous northwesterly jet stream flow in 2013 kept the west coast dry while bringing cool air from Alaska and Canada to the central and eastern U.S.
In December 2013 extraordinarily high pressure covered the Gulf of Alaska. unusually warm air extended from the Gulf of Alaska, to Siberia. A flow of cold air developed from the American side of the Arctic ocean towards northern plains of the U.S. leading to a series of Arctic air outbreaks in the central and eastern U.S. (and today's cold weather).
Siberian ducks splashing water in December in the ice free River Yenisei. Incredible.
"The images of the River Yenisei with ducks splashing in the water, and grass in the parks, could be from autumn rather than deep in the winter in a city where December temperatures have gone as low as minus 47C."
While Siberian ducks were splashing, California reservoirs were drying up. California records for dryness were obliterated in 2013. After a surge of warm water across the tropical Pacific ended in fall 2012 with a failed El Nino, the rains stopped. Santa Cruz, which normally has 30 inches of rain in a year saw just 4.78 inches in 2013, a stunning drop from the previous record low of 11.85 inches.
California water supplies were in good shape entering 2013 but they are rapidly deteriorating now. Snowpack levels are just 20% of normal on January 3, 2014 according to automated measurements.
California's snowpack is 20% of normal on January 3, 2014 according to automated measurements.
There's no end to the west coast drought in sight. The Climate Prediction Center outlook for California is for worsening drought for the next 90 days. The January outlook is very disappointing because January is frequently California's wettest month.
The climate prediction center forecasts a dry January for California.
What's causing this bizarre jet stream pattern? It's tied to very warm oceans and the distribution of heat in the oceans. I suspect the weakening of the thermohaline circulation around Antarctica resulting from the freshening of the waters is driving an acceleration in the trade winds and the ocean currents. About 20% less water is sinking around Antarctica, so the thermal gradient is increasing around Antarctica. This is paradoxically increasing Antarctic winter sea ice while the global oceans warm up faster than expected. That's to be expected when Antarctic ice is rapidly melting from below in the summer, freshening the surface waters around Antarctica.
Of course, there are natural cycles and there's always natural variability, but I suspect that the changes around Antarctica and in the Arctic are irreversibly changing the ocean currents and global climate. Whatever the cause, the severe drought in California is getting worse and there's no relief in sight.