A crack runs through the front of the San Rafael Glacier and an iceberg the size of a 10-story building falls into the lagoon. In southern Chile, glaciers are an “excellent indicator” of the effect of climate change.
Hundreds of icebergs float adrift in the San Rafael lagoon, whose surface is a visible example of the disproportionate increase in the melting of 39 glaciers emanating from the Northern Ice Field, in the southern region of Aysén. Together with the Southern Ice Field, they form the third largest mass of ice in the world, behind only Antarctica and Greenland.
The 3,500 kmtwo of frozen surface of the Northern Ice Field, added to the 11 thousand kmtwo of the Southern Ice Field, represent 63% of Chile’s glacial surface.
150 years ago, the tongue of the Andean San Rafael glacier extended in a mushroom shape covering two-thirds of the lagoon, but now the front that breaks up (the glacier wall) has receded 11 kilometers towards the interior of the valley and no longer appears in the lake.
This is a phenomenon that also occurs in practically all of the country’s 26,000 glaciers — only two have grown — explains Alexis Segovia, 42, a glaciologist at the Glaciology and Snow Unit of the General Directorate of Waters (DGA) in Chile.
“Glaciers are an excellent indicator of climate change because they are ice and react to higher temperatures”, says the expert. What’s more, these surfaces “return a lot of radiation that reaches Earth” and if they keep getting smaller, the planet “will heat up faster.”
“There’s no way back”
On the opposite side of the Northern Ice Field, the Exploradores glacier is shrinking irreparably, explains to AFP Andrea Carretta, a 45-year-old Italian who has been a forest ranger in this area for five years.
“It is getting worse every day because the glacier is retreating and in summer it is losing 13 centimeters of ice per day. In winter it is losing between 2 and 3 centimeters”, he explains.
“There’s no way back”, he laments in the face of the huge expanse of ice — 5 kilometers wide and 22 kilometers long — and that every day expands its moraine — something like the “remains” of the glacier when it melts and accumulates rocks.
Your ice is melting fast. Glaciers “are a thermometer, instruments where we will perceive the effects of climate change soon after,” says Carretta.
‘GLOF’ danger
The melting of a glacier is a natural phenomenon that climate change has accelerated “significantly”, Jorge O’Kuinghttons, 45, head of the DGA’s Regional Glaciology Unit, told AFP.
Less precipitation and an increase in temperature due to climate change lead to melting of ice on the sides of the glacier. Because of this, lakes are formed that increase in number and volume over time.
Damned by ice, these lakes end up being discharged abruptly, generating an immense flood called ‘glacial lake overflow flood’ (GLOF), explains the scientist.
In early 2010, a GLOF generated on the Exploradores Glacier triggered an overflow of water that caused a 10-meter high flood and, although it left no casualties, it ended up inundating homes, crops and livestock. In Peru, in the 1950s, a similar phenomenon occurred on the Blanco glacier, leaving approximately 5,000 dead.
