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California Experiencing Driest Year on Record, Epic Drought to Persist or Intensify Through Summer, Godzilla El Nino Waits in the Wings
9
May, 2014
8.83
inches. That’s the total average precipitation accumulation for the
state of California so far for the first four months of this year.
Out of the entire climate record, this paltry accumulation is less
than that received during any similar period of any year since 1895.
Overall,
rainfall totals throughout the state remained below 26 percent of
typical levels for this time of year. And with California entering
its third year of drought, the state would have to receive an average
of 53 inches between now and October, more than 10 inches of rainfall
each month, to break the current and very extreme ongoing drought.
(Drought
monitor color graphic of California drought as of May 6. Tan =
moderate drought. Orange = severe drought. Red = extreme drought.
Dark Red = exceptional drought. Image source: Drought
Monitor.)
As
of late April, the drought had expanded to cover every corner of the
state leaving not an inch of this critical agricultural region
untouched. Drought continued to intensify, bringing with it water
stress, cracked soil, crashing reservoirs and heavy strains to farms,
businesses, cities and individuals. By May 6, fully 77 percent of
California stifled under severe or extreme drought conditions.
The
drought has become so severe that water-strapped cities like Santa
Cruz have resorted to the most dire measures,
including rationing, to husband dwindling water supplies. Last week,
the city, which depends on some of the most vulnerable and
thinly-stretched water resources in the state, announced a number of
severe fines to water consumers exceeding assigned usage levels. The
fines could quickly double, triple, or even quadruple water costs for
any non-farm water consumer within the city.
Across
the State, various desperate water conservation regimes have been put
in place with the Federal Government announcing earlier this
year that
it would be forced to stop water allocations to farmers in an
unprecedented move to stave off further declines in stores.
Unfortunately,
the persistent high pressure blocking pattern off the US West Coast,
which has hovered in the same region for more than a year, remains in
place even as it continues to deflect rain-bearing storms north
toward the Washington and Canadian coasts.
This
pattern — arising from a set of abnormal atmospheric conditions
including added heating through human-caused warming and a Jet Stream
that has the tendency to become stuck more and more often as sea ice
erodes — results in a high likelihood that drought will remain or
intensify for California and much of the US Southwest throughout this
summer.
Climate
Prediction Center analysis, shown above, projects that the current
California drought will persist or worsen for the entire state
through at least July 31rst. If relief does come, it will arrive many
months from now. For the most likely chance for a change in the
weather doesn’t appear until fall and winter of 2014. And this
potential brings with it the risk for a radical switch to yet another
damaging climate extreme.
Hoping
For El Nino is Like Praying to Godzilla
Yesterday’s
report from NOAA indicating a near 80 percent chance of El Nino by
the end of this year provided some hope for additional rainfall after
what is expected to be a very dry and difficult summer.
But given current atmospheric conditions, the El Nino event would
have to be in the moderate-to-strong range to both overcome what is a
demonically persistent blocking pattern and to deliver enough
moisture to make up the severe rainfall deficit. Anything less would
be too weak to cure the current drought. But something stronger may
well kill the patient.
Unfortunately,
there remains a substantial risk that the 2014-2015 El Nino event
could be a Godzilla of a thing — a monstrous outburst of the
extreme ocean heat storage of the past 16 years that Dr. Kevin
Trenberth has warned could well come back to haunt us. A record high
ocean heat content that is out there, lurking in the Pacific Ocean
even now. And it’s the potential that this heat will hit the
surface with a severity rivaling or even exceeding the epic 1998
event that should well be cause for a different kind of concern.
In
such an instance, the onrush of heavy rains would be less a relief
and more a switch from extreme drought to extreme flood. During the
1998 event more than 20 California counties were declared disaster
areas due to the sudden deluge. But with human warming amping up the
hydrological cycle by more than 6% and with such a large and vicious
store of ocean heat waiting to be released, a severe El Nino at this
stage might look more like an Arkstorm — an event which could dump
many feet of rain over a period of weeks.
On
the other hand, if the El Nino fizzles into only a minor event and
that massive ocean heat store decides to lay in wait for another year
or two or three, California is much more likely to remain locked in a
continued multi-year dry pattern. So the best California could hope
for is to thread an El Nino needle and receive a just-right moderate
to strong El Nino. But with the current climate regime favoring
extremes, the possibility for such a just-right occurrence is quite a
bit lower than either the Godzilla or the fizzle.
In
any case, both added heat and dryness are set to intensify over
coming years and decades for California. This ongoing ratcheting is
the direct result of human-caused climate change. A result that will
either be bad or terrible depending on whether or not we decide to
rapidly reduce and eliminate our greenhouse gas emissions.
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