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Retreating glaciers
Glaciers, recognized as a good indicator of climate
change due to their sensitivity to temperature
increase, are already experiencing its drastic effects.
Climate change is expected to cause increased
melting in the future, especially for tropical glaciers
(Rabatel et al., 2013) such as those in the Tropical
Andes, which range from about 4,000 to 6,500 m
altitude. To date, melting has been most prominent
in small and low-lying glaciers. The significant
melting of tropical glaciers is possibly due to high
radiation and moist tropical climate dynamics
(Ibid.). Beyond the direct warming of the glaciers
by air temperature, precipitation falling as rain
instead of snow contributes to melting by reducing
the albedo of the glacier surfaces. El Niño events are
also associated with reduction in glacier mass, due
to the higher temperature and reduced precipitation
(Francou et al., 2003; Jeschke, 2009).
The Andes contains 99 per cent of the world’s
tropical glaciers (Chevallier et al., 2010). This
amounts to 0.8 per cent of the world’s glacial
area (not including Antarctica) (NCIDS, 2008).
The remaining tropical glaciers are located in
Africa and New Guinea, with a total area of less
than 10 km². The total area of glaciers in the
Tropical Andes was 1,920 km² about 10 years
ago (Francou and Vincent, 2007), with 71 per
cent in Peru, 20 per cent in Bolivia, 4 per cent in
Ecuador, and 4 per cent in Colombia-Venezuela
(Rabatel et al., 2013). The overall area of glaciers
in the Tropical Andes has diminished further
since 2007.
Glaciers in the Tropical Andes
Equator
Tropic of Capricorn
Sucre
Lima
Quito
Bogota
Caracas
Castries
Roseau
La Paz
The Tropical Andes eco-regions
SURINAME
FRENCH
GUIANA
GUYANA
BRAZIL
PARAGUAY
PERU
BOLIVIA
ECUADOR
COLOMBIA
VENEZUELA
Cultural landscape
Xeric and seasonally dry montane forest
Evergreen montane forest
Shrubs
Páramo ecosystems
Other forest ecosystems
Water body
Glacier
Exposed soil
Desert and other xeric ecosystems
Grassland ecosystems of the Yungas
Puna ecosystems
Source: CONDESAN
FIGURES