Tibetan Plateau South America
The Tibetan Plateau and surrounding regions in China Glaciers in South America cover an area of about 25 700
have a total glacier area and volume of 59 400 km
2
and square km
131
, mainly in the Patagonian Icefields, which
5600 km
3
, respectively. Glaciers in China have been re- represent 66 per cent of South America’s total ice area
132
.
treating with an area loss of about 20 per cent since the Chile has by far most of the glaciers; Argentina has an
Little Ice Age maximum extent in the 17th century
125,126
. important number of ice bodies all along the Andes;
Retreat increased during the last century, especially dur- Venezuela has less than 2 km
2
of ice at Pico Bolivar
133
.
ing the past ten years
127,128
. Several monitored glaciers Less than 10 per cent of the glacier area is located in the
show strong retreat. About 90 per cent of glaciers are tropical Andes
134
(see box on tropical glaciers).
retreating, and glacier retreat increases from the con-
tinental interior to the coastal margins
127,128
. With the In southern Patagonia, the glacial advance appears to
impact of global warming on the region
127,129,130
, glacier have peaked between the late 17th and early 19th centu-
shrinkage will be faster and pose a serious threat to wa- ries
135
. Medium and small glaciers in central Chile and
ter resources in this region (see box on the water towers Argentina have shrunk considerably. This will affect the
of Asia, at the end of Part 1 of this chapter). future availability of water resources, as these glaciers
can contribute up to 68 per cent of meltwater during dry
seasons. (See box on glacier changes and water availabil-
ity in the tropical Andes). Most of the calving glaciers in
Patagonia have also experienced drastic retreat
136
, con-
tributing significantly to sea level rise
27,137
. Ice avalanch-
es in the cordillera have resulted in many thousands of
deaths (see box on the deadly avalanches of Glaciar 511
in the Cordillera Blanca).
140 GLOBAL OUTLOOK FOR ICE AND SNOW