Dry
February sends California back to drought: 'This hasn't happened in 150 years'
California
February is
typically one of the wettest months in California, but the state is parched,
and there’s no moisture in the forecasts
Susie Cagle
Fri 21 Feb
2020 11.00 GMTLast modified on Fri 21 Feb 2020 13.41 GMT
San
Francisco and Sacramento have not seen a drop of rain this February, and
climate scientists are expecting that disturbing dry trend to hold, in what is
typically one of the wettest months of the year for California.
“This
hasn’t happened in 150 years or more,” said Daniel Swain, a climate scientist
at UCLA’s Institute of the Environment and Sustainability. “There have even
been a couple wildfires – which is definitely not something you typically hear
about in the middle of winter.”
Combined
with warmer than average temperatures, the state is parched, and there is no
moisture in the forecasts. “The dryness has picked up as the season has gone
on,” said Swain.
The year
began with snowpack at 90% of its historical average. But less than two dry,
warm months later, it’s hanging in at just 52% of average.
“Those
numbers are going to continue to go down,” said Swain. “I would guess that the
1 March number is going to be less than 50%.”
That snow
isn’t just the basis for the mountain tourism industry in the winter – it
serves as a significant source of water for California cities and agriculture
come spring melt.
Last year’s
snowpack at this time was more than 125% of average, an indicator of what Swain
calls “precipitation whiplash”. California has long weathered these wet and dry
cycles. The state’s future in the climate crisis looks warmer and drier not
because of a lack of rain, but because of the extra heat drawing moisture out
of the ecosystem. That heat is a major contributor to reduced snowpack, both as
less snow falls, and as more of it melts more quickly. Climate science points
to a California bound for a future that looks less like endless extreme drought
alone.
“We aren’t
going to necessarily see less rain, it’s just that that rain goes less far.
That’s a future where the flood risk extends, with bigger wetter storms in a
warming world,” said Swain.
The
2011-2017 drought was the worst since record-keeping began. It reshaped
California’s landscape and its regulations, and memories of water rationing still
loom large in the state’s memory.
“Some folks
will say you’re not in a drought until there’s water scarcity problems,” said
Swain. “We have a fair bit of single-year drought resilience. No matter how
severe it is, the cities and most of the [agriculture] zones won’t run out of
water.”
The more
immediate impacts of this trend will be on the ecosystem and the inevitable
fire season, as California’s grasslands and forests continue to dry out.
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