Cities in peril as Andean glaciers melt
Pastor Dale Morgan
Cities in peril as Andean glaciers melt*
Ice sheets expected to last centuries could disappear in 25 years,
threatening water supplies
John Vidal, environment editor
Tuesday August 29, 2006
The Guardian
Andean glaciers are melting so fast that some are expected to disappear
within 15-25 years, denying major cities water supplies and putting
populations and food supplies at risk in Colombia, Peru, Chile,
Venezuela, Ecuador, Argentina and Bolivia.
The Chacaltaya glacier in Bolivia, the source of fresh water for the
cities of La Paz and El Alto, is expected to completely melt within 15
years if present trends continue. Mount Huascarán, Peru's most famous
mountain, has lost 1,280 hectares (3,163 acres) of ice, around 40% of
the area it covered only 30 years ago. The O'Higgins glacier in Chile
has shrunk by nine miles in 100 years and Argentina's Upsala glacier is
losing 14 metres (46ft) a year.
Although a few glaciers in southern Patagonia are increasing in size,
almost all near the tropics are in rapid retreat. Some glaciers in
Colombia are now less than 20% of the mass recorded in 1850 and Ecuador
could lose half its most important glaciers within 20 years.
The rate of glacier retreat has shocked scientists, says a report on the
effects of global warming in Latin America by 20 UK-based environment
and development groups who have drawn on national scientific
assessments. Their study says climate change is accelerating the
deglaciation phenomenon.
"The speeding up of the ... process is a catastrophic danger," says
Carmen Felipe, president of Peru's water management institute. In the
short term, the president says, it could cause overflows of reservoirs
and trigger mudslides, and in the longer term cut water supplies.
According to the Colombian institute of hydrology, back in 1983 the five
major glaciers in El Cocuy national park were expected to last at least
300 years, but measurements taken last year suggest that they may all
disappear within 25 years. Meanwhile, the ice sheet on the Ecuadorean
volcano Cotopaxi and its glacier has shrunk by 30% since 1976.
"The [drastic melt] forces people to farm at higher altitudes to grow
their crops, adding to deforestation, which in turn undermines water
sources and leads to soil erosion and putting the survival of Andean
cultures at risk," says the report by the Working Group on Climate
Change and Development, which includes the International Institute for
Environment and Development, Christian Aid, Cafod, WWF, Greenpeace and
Progressio.
Their report, Up in Smoke, says snow and rainfall patterns in South
America and the Caribbean are becoming less predictable and more
extreme. "East of the Andes, rainfall has been increasing since about
1970, accompanied by more destructive, sudden deluges. Meanwhile, the
last two hurricane seasons in the Caribbean rim have caused $12bn
(£6.3bn) damage to countries other than the US. Tropical storms are
expected to become more destructive as climate change intensifies.
Climate change models predict more rainfall in eastern South America and
less in central and southern Chile with a likelihood of greater and
opposite extremes. The 2005 drought in the Amazon basin was probably the
worst since records began."
Rises in sea level are expected to be especially severe in the region
over the next 50 years, with 60 of Latin America's 77 largest cities
located on the coast. The first hurricanes have recently hit south of
the equator line in Brazil. "The net effect ... is to reduce the
capacity of natural ecosystems to act as buffers against extreme weather."
"What we are seeing are many more negative and cumulative impacts. The
larger the rate of [climate] change, the more the adverse effects
predominate. Climate change is set to turn an already rough ride into an
impossible one," says the report, which adds that the impact of climate
change is "hugely" magnified by existing environmental abuse.
It proposes that Latin American governments do not repeat the mistakes
made by past and present North American and European governments.
Several countries in the region are proposing a new generation of mega
dams which would displace thousands more people and destroy vast areas
of the Brazilian Amazon. The new importance of soya, both as a food and
biofuel crop, could also devastate the environment, leading to a battle
for land between companies.
Large-scale coal, oil, and copper mining not only threaten fragile
environments, says the report, but in some cases can physically endanger
remaining glaciers and greatly increase climate changing emissions. "The
Pascua Lama project on the borders of Chile and Argentina intends to
move three glaciers that cover gold, silver and copper deposits. The
glaciers sustain the mountain and valley ecosystems and there are fears
that toxic wastes used in the mining will contaminate land and water,"
says the report.
Yesterday, the groups called on rich countries to urgently reduce
greenhouse gas emissions and proposed that Latin America and the
Caribbean governments be helped to reduce their vulnerability to extreme
weather.
"The only option we have, apart from demanding that developed countries
take responsibility for the damages that climate change is causing, is
to try to neutralise the adverse impacts that are [already] upon us. It
is time to rethink the model of international aid," said Juan Maldonado,
former Colombian environment minister and president of the UN convention
on biological diversity.
Backstory
"With each new flood, drought or hurricane in Latin America, precious
gains in poverty reduction are lost. Extreme weather is set to cause
massive loss of life in developing countries throughout the region. The
international community must invest more in helping poor communities
cope with the effect of climate change," said Simon Trace, chief
executive of Practical Action.
The world's many thousands of glaciers have been stable or in slow
retreat for more than 100 years but since around 1980 they have mostly
been retreating drastically. The fastest decline is in the Himalayas,
the Arctic, the Alps, the Rockies and the tropics. Most glaciologists
believe this natural phenomenon is being accelerated by global warming.
The effects of glacier melt are expected to be severe. Hundreds of
millions of people in Asia and Latin America are dependent on glacier
water. A reduction in runoff will affect the ability to irrigate crops
and will reduce summer stream flows to keep dams and reservoirs
replenished. In Norway, the Alps, and the Pacific north-west, glacier
runoff is important for hydropower. If all the ice on the polar icecaps
were to melt, the oceans would rise an estimated 70 metres (230ft). But
even a small melt will affect coastal life.