Two views of California captured by
NASA’s Terra satellite use false color to differentiate between clouds
(whitish) and snow (orange-red). The first image was acquired on Nov. 25, 2014,
before two storms hit California. The second is from Dec. 13th, after the
second storm. If you’ve been following news reports about California’s
epic drought in the aftermath of the recent storms there, it would be
understandable if you’ve found yourself perplexed.
“Finally, Some Good News In The
California Drought” read the headline in Huffington Post. “Flood-Causing Deluge Amounts to Just Drops in
California Drought” proclaimed the New York Times’ glass-almost-empty headline:
Refilling the glass a bit, the San
Jose Mercury News stuck to reporting facts: “Winter storms finally starting to boost storage levels
in key reservoirs”. Meanwhile, Wired, like the Times, spun the story gloomily :
“Think California’s Huge Storm Will End the Drought? Think Again”
As you probably know (assuming you haven’t
been in hibernation), California has been on the receiving end of a veritable
gusher of atmospheric moisture originating in the tropical Pacific. The first blast from this so-called “Pineapple Express” firehose came on
December 2. The second — and more powerful — round of storminess hosed
California starting overnight on Dec. 10th and continuing through the
11th. It dumped an extraordinary amount of moisture.
In its story, the
Times quoted Jon Gottschalck of the Climate Prediction Center as
saying, “Most of the precipitation was rain…It wasn’t really adding to
the snowpack, which is really what they need…Certainly this is good. But
it’s going to be just a minor dent in the drought.”
But as Paul Rogers reported in his
excellent Mercury News story, the state’s two largest reservoirs, Shasta
Lake near Redding, and Lake Oroville in Butte County, were projected to
receive 510,000 acre-feet of water in storm runoff by Tuesday.
That’s a staggering amount of water
— 166 billion gallons from a single storm, enough water for 2.5 million
Californians for a year. It would fill half a million football fields one-foot
deep…
If you have any doubts, consider
what Bill Patzert, a climatologist with NASA’s Jet Propulsion
Laboratory, has to say. He’s an eyewitness on the ground in Pasadena, and in an
email message to me today he proclaimed: “I see snow!”
But as we know, looks on photos can
be deceiving. So let’s check the actual numbers:
A comparison of the snowpack in
California’s Sierra Nevada range on Nov. 29 and Dec. 12. (Source: California
Department of Water Resources)
These maps show something called
“snow water equivalent,” which is a measure of the water content of snow. The
map on the left shows conditions on November 29th. Zip, nothing nada — 0%
of normal for the date in all three Sierra regions. But in just two weeks, the
snowpack has gone from zero to as much 45%.
I don’t know about you, but that
sure doesn’t seem like the precipitation wasn’t really adding to the snowpack.
So let’s just cut to the chase
(with more details to follow): The Times blew it, as did other media
outlets.
This is not to say that the storms
have erased California’s drought. How could they? If recent research
is correct, it has been the worst in 1,200 years. Reservoir levels
have dropped precipitously, soil moisture levels have been very low, and
groundwater depletion has accelerated.
Paul Rogers of the San Jose Mercury
News reports that it will take six additional big storms — and a
season with precipitation well above average — to erase
this drought.
Bill Patzert is ebullient and
cautious, at the same time. Here’s the heart of his email message to me:
Some facts:
1.
It’s early in the snow season: too
early to claim success or defeat. But I can see snow!
2.
El Nino is a wannabe: assessing the
impact of some warmer H2O in the Central Pacific on California rainfall is
fuzzy.
3.
The recent December rains cheer me:
way better than the past three years.
4.
Busting the drought will take years:
we do it inch by inch, not yard by yard.
5.
Nobody predicted these December
storms in November, so be careful what they say about Jan, Feb and Mar!
6.
Beware of false prophets …. I know.
I’ve been guilty! But I’m in therapy …..
Loving the rain, Bill Patzert
His reference to El Niño is
interesting. I’m sure many Californians are looking hopefully to the Pacific
Ocean, waiting for a full-blown El Niño to take shape out there. This
phenomenon tends to increase the odds of a wet winter and spring for
California.
NOAA pegs the odds of an El
Niño finally developing this winter at 65%. Of course, nature has a way of defying forecasts. El Niño
could sputter, and other manifestations of natural variability could
intervene to push things onto a different course. But I’m sure most
Californian’s will welcome whatever moisture does come their way (putting aside
the damage that flash flooding and mudslides can cause).
And I’m sure they’re relieved by
what has happened so far. I sure am, and I don’t even live there.
The
entire post with graphics and photos can be found at: http://blogs.discovermagazine.com/imageo/2014/12/14/news-media-fail-storms-did-ease-california-drought/#.VI6zjnvRV2I
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