Tuesday, April 9, 2013

The dramatic retreat of the Andean glaciers over the last 30 years

Institut de recherche pour le developpment, the Media Centre: The glaciers in the tropical Andes shrunk between 30 and 50% in 30 years, which represents the highest rate observed over the last three centuries. IRD researchers and their partners( 1) recently published a summary which chronicles the history of these glaciers since their maximum extension, reached between 1650 and 1730 of our era, in the middle of the Little Ice Age*. The faster melting is due to the rapid climate change which has occurred in the tropics since the 1950s, and in particular since the end of the 1970s, leading to an average temperature rise of 0.7°C in this part of the Andes. At the current pace of their retreat, small glaciers could disappear within the next 10 to 15 years, affecting water supply for the populations.

 For the first time, a study conducted by IRD researchers and their partners(, recently published in the journal The Cryosphere , provides a retrospective of more than three centuries on glacier evolution in the entire tropical Andean region .

Since their maximum extension, reached between 1650 and 1750, during the Little Ice Age , the tropical Andean glaciers have gradually retreated. Over the last 30 years, however, their decline has taken dramatic proportions. This summary clearly shows the peculiarity of these last decades, with melting speeds that had never been reached before in 300 years: the surface areas of glaciers in Colombia, Ecuador, Peru and Bolivia were reduced from 30-50% since the end of the 1970s and up to 80-100% in extreme cases. This new study confirms the acceleration of climate change in this part of the world at the end of the 20th century.

...Today, it is vital to improve forecasts in order to better anticipate future impacts on Andean populations. Mountain glaciers help regulate water resources throughout the year. Millions of people living in the Andes depend on it during the dry season for purposes of agriculture, hydroelectric energy and urban consumption.

The CasaƱo Overa glacier in Argentina spills down over cliffs, leaving waterfalls and the 'thunder' of falling ice that gives the mountain its namesake. Shot by McKay Savage, Wikimedia Commons via Flickr,
under the Creative Commons Attribution 2.0 Generic license

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