Saturday, January 30, 2016

El Niño Is Here, So Why Is California Still in Drought?

Lake Oroville up more than 20 ft. in the last week! It is at 34% of capacity! (Credit: twitter.com / CA-DWR) Click to Enlarge.
A parade of El Niño-fueled storms has marched over California in the last few weeks, bringing bouts of much needed rain and snow to the parched state.  But maps of drought conditions there have barely budged, with nearly two-thirds of the state still in the worst two categories of drought.

So what gives?

The short answer, experts say, is that the drought built up over several years (with help from hotter temperatures fueled in part by global warming) and it will take many more storms and almost assuredly more than a single winter — even one with a strong El Niño — to erase it.

The issue for California comes down to this:  there are short-term drought impacts and long-term ones.

With the former, the signs are encouraging:  Soil moisture is increasing and some areas are greening up thanks to repeated rains.  Temperatures have also been cold enough that snow is building up in the mountains.  The snowpack in the Sierra Nevada, a major water resource come spring and summer, is up to an average of 113 percent of normal for this time of year, according to California’s Department of Water Resources (DWR).  Compare that to the record low 6 percent of normal at the end of winter last year.

“The good news is we are seeing the benefits of El Niño, but they are trying to climb out of a 4-year drought,” Mark Svoboda, a climatologist with the National Drought Mitigation Center at the University of Nebraska-Lincoln, said in an email.

Long-term impacts like depleted groundwater, low reservoir levels and pitiful stream flows, “they’re not responding much at all yet,” Brian Fuchs, another NDMC climatologist, said.  “The reservoir levels have hardly moved.”

Read more at El Niño Is Here, So Why Is California Still in Drought?

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