After nearly two decades
of declining water flows
into the Colorado River Basin,
scientists tried to get
more attention by inventing
a new term: “mega-drought.”
View Lake Mead in a 2007 photo:
The North American
Southwest has been dry
over the past two decades.
Archaeological evidence
has linked previous
decades-long droughts
to several historical
societal collapses,
including the Mayan
civilization and
Kublai Khan’s
Yuan dynasty
in China.
The researchers,
led by A. Park Williams
of the Lamont-Doherty
Earth Observatory of
Columbia University,
say this prolonged
mega-drought —
which reached from
Oregon and Idaho,
down to northern Mexico --
was allegedly one of the
worst mega-droughts
in human history.
That is pure speculation.
The Colorado River’s
biggest reservoirs,
Lake Mead and Lake Powell,
are now roughly half-empty.
The Colorado River
irrigates 5 million acres
of farmland, and provides
water to 40 million people
in seven states — including
in the West’s biggest cities
like Los Angeles, Phoenix
and Denver.
Thanks to diversions
for various human uses,
the river now runs dry
before it reaches the sea.
More water rights
have been allotted
than nature can fulfil.
A 2017 study published
in Water Resources Research
said Colorado River flows
between 2000 and 2014
were 19% below normal.
Reduced rainfall
was partially
responsible.
That is a fact.
One-third of the runoff
decline allegedly resulted
from warming temperatures.
That is a wild guess.