Page 92 - HISTORY ANGKOR

HERITAGE

AT RISK

THE EFFECTS of global climate change even greater danger. Reductions of
are threatening hundreds of sites sea ice, which had protected coastal
that hold clues to Alaska’s past and areas from battering storms, mean
its people’s heritage. The permafrost that a single severe weather event
that once preserved centuries-old can cause erosion as far as 100 feet
artifacts is thawing—quickly. As inland. Flooding has not only caused
artifacts are exposed, they are sus- coastlines to recede; it has also
ceptible to decay and rot. Scientists swept away buried archaeological

estimate that the nine million square sites. Experts predict that sea levels
miles that make up the Arctic are will continue to rise in the coming
warming two to three times faster decades, which means that parts
than the rest of the planet. In south- of Alaska’s western coast will suffer
ern regions of Alaska, rising sea levels storm surges that could regularly top
and the Bering Sea’s winter storms 10 feet. Thawing permafrost in low-
are putting coastal heritage sites in lying areas is causing the land to sink.

B B

A S I A AFRICA S S e a
EUROPE

R U S S I A

Maximum
extent of
permafrost
ARCTIC
1900
ARCTIC
CIRCLE
North Greenland 2100
Pole
OCEAN

GLOBAL DECLINE

AREA C A N A D A Permafrost, ground that is frozen all
ENLARGED year, is protected by a layer of soil that
N O R T H
ALASKA N O R T H typically freezes in the winter. In recent
(U.S.)
PAC I FI C A M E R I C A years in many regions, it has not frozen,
A M E R I C A
O CE AN UNITED allowing underlying layers of permafrost
STATES to thaw. Models based on current levels
0 mi 1,000
of greenhouse gas emissions project
0 km 1,000 that by the year 2100 more than 50
percent of near-surface permafrost
worldwide will be gone.
NG MAPS

90 MARCH/APRIL 2022