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SCIENCEMonday 7 March 2016
NASA: Drought in 1998-2012 in Mideast worst in 900 years
DANIELLA CHESLOW
Associated Press
JERUSALEM (AP) — A re-
cent, 14-year dry spell in
the Middle East was the
worst drought in the past
900 years, according to a
new NASA study released
this week.
NASA’s researchers ex-
amined records of rings of
trees in several Mediter-
ranean countries to deter-
mine patterns of dry and
wet years across a span of
900 years. They concluded
that the years from 1998 to
2012 were drier than any
other period, and that the
drought was likely caused
by humans.
The study’s lead author Ben
Cook said the range of ex-
treme weather events in
the eastern Mediterranean
has varied widely in the
past nine centuries, but the
past two decades stand
out.
“This recent drought falls
outside the range of natu-
ral variability,” he said.
Drought has continued in
parts of the Middle East, he
added.
Cook is a climate scientist
at NASA’s Goddard Insti-
tute for Space Studies and
the Lamont Doherty Earth
Observatory at Columbia
University in New York City.
The researchers used re-
cords of tree rings in North- They studied rings of trees,
ern Africa, Greece, Leba-
This Feb. 8, 2007 file photo shows sink holes on the shoreline of
the Dead Sea near the town of Ghor Haditha in Jordan, showing
the retreating sea water line.
non, Jordan, Syria and
Turkey, and combined the
data with records from
Spain, southern France and
Italy to examine patterns of
drought across time in the
region.
both living and dead, that
were sampled all over the
region. Rings in the trunks of Columbia University and
the University of California ence Center at Penn State
Santa Barbara found that University, said the NASA
drought triggered a col- study is one of several wor-
lapse in agriculture in Syria rying reports about unprec-
and the migration of 1.5 edented climate condi-
million farmers to the cities, tions.
straining resources. Mann was not involved in
The water shortage was NASA’s study.
one of several contributing In an e-mail to The Associ-
factors that had worsened ated Press, Mann noted
the situation in Syria in the that tree rings “have their
lead-up to the outbreak of limitations and uncertain-
that country’s devastating ties,” but said “the au-
civil war in 2011. thors have done a reason-
Michael Mann, director able job in assessing the
of the Earth System Sci- uncertainties.”q
Associated Press
trees represent years. Thin
rings indicate dry years;
thick rings show years when
water was abundant.
Cook said the research
supported other studies in-
dicating human causes of
extreme climate events.
Last year, researchers at