KPBS Drought Tracker Update: Falling Short Of A Drought-Busting Year
Thursday, March 10, 2016
California's seasonal rain and snow levels have grown over the past week — but not by much. The latest update from the KPBS Drought Tracker shows the state on track for a fairly average wet season.
As of Thursday morning, statewide rain levels were at 94 percent of what normally accumulates between Oct. 1 and April 1. Average Sierra Nevada snowpack levels were at 84 percent of the seasonal normal.
Those gains add up to about 10 percent growth over the past week. But recent storms haven't been enough to catapult California into drought-busting territory.
Scripps Institution of Oceanography climate researcher Dan Cayan, who helped compile data for the KPBS Drought Tracker, said to truly put a dent in the drought, those numbers would have to hit 150 percent by April 1.
"We're probably not going to see 150 percent," Cayan said. "Which is at the upper end of the precipitation that might've been expected even in a heavy year."
Previous strong El Niños have delivered much more rain and snow to California. On this day in 1998, snowpack levels were at 160 percent of the seasonal normal, about double what they are today.
But this year, Cayan says high pressure ridges have been diverting storms away from California. That caused precipitation to stagnate in February.
"Things were more active in the last week, but we're having to make up for what didn't happen in February," Cayan said.
Cayan says it's not all bad news, though. This year remains a major improvement over 2015's dismal lows, and parched ecosystems could be refreshed by increased rainfall.
However, he said it remains to be seen how much El Niño will improve California's water supply.
"I think if we continue at present, it's unlikely we're going to refill — to the extent we might have hoped for — the California reservoir system," Cayan said.
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