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https://www.cnn.com/2022/06/16/us/southwest-drought-flooding-climate/index.html
The West just experienced an aspect of the climate crisis that scientists have warned of for years
(CNN)The West saw an aspect of the climate crisis play out this week that scientists have warned of for years.
In the middle of a prolonged, water shortage-inducing megadrought, one area, Yellowstone,
was overwhelmed by drenching rainfall and rapid snowmelt that --
instead of replenishing the ground over a matter of weeks or months --
created a torrent of flash flooding that ripped out roads and bridges and caused severe damage to one of the country's most cherished national parks.
In
the meantime, drought conditions persisted in the Southwest, where
water is desperately needed to replenish the country's largest
reservoirs, and provide relief to regions tormented by record-setting
wildfires.
The latest update in
the US Drought Monitor on Thursday showed the major contrast between
the wet Northwest and the hot and dry Southwest. This feast-or-famine
contrast is a pattern the climate crisis tends to amplify: extremes on
both ends of the spectrum, with the pendulum sometimes swinging suddenly
from one side to the other.
Across
the Pacific Northwest, drought conditions improved significantly over
the past several weeks, with the areas in severe drought falling from a
high of 55% in April to 25% this week.
"Much
of the Northern Tier states experienced beneficial rainfall and near to
below-normal temperatures, predominantly leading to drought
improvements from the Pacific Northwest to the Northern Plains," the
Drought Monitor noted.
But
this persistent and active storm track, which continues to bring rain
and snow to the Northwest, has largely missed California and the
Southwest.
The US Bureau of Reclamation
projected this week that Arizona, Nevada and California would see even
more significant cuts to their Colorado River water allotments starting
next year.
Federal officials make those determinations on a year-by-year basis every August. Lake Mead,
the nation's largest reservoir which serves millions of people in the
Southwest, is already running well below what last year's projections
suggested, even in its worst-case scenario. Last August, the bureau
predicted the reservoir would most likely be at 1,059 feet above sea
level at the end of this month, and 1,057 feet at worst. But it's now
around 1,045 feet.
In
New Mexico, where two of the largest fires in state history are still
burning, the drought summary noted that temperatures were running around
5 to 10 degrees Fahrenheit above average, which are worsening drought
conditions in parts of western and southern New Mexico.
More
than 50% of the state is in exceptional drought, the highest
classification in the drought monitor, up from zero in January. This
extreme dryness is playing a major role in fueling a fire year that is
pacing to be the worst on record.
A recent study from the federal government's Los Alamos National Laboratory in New Mexico
found that parts of the Upper Colorado River Basin, including the
states of Colorado, Wyoming and Utah, will see earlier peak streamflow
because of earlier rapid snowmelt, and up to 60% reduction in snow in
the coming decades.
"We're
definitely looking at a hotter future," Katrina Bennett, hydrologist
with the lab and lead author of the study, told CNN. "There will be more
of that wet to dry sort of scenarios we're seeing, but regardless,
we're going to see more minimum streamflow, increase in drier soils and
lower snowpacks, which all together will lead to likelihood of drought
increasing across the board especially in the upper areas where we
really haven't seen that intense drought stress yet."
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