Tap runs dry as glaciers recede

MCGILL (CAN) — Glaciers are retreating at an unexpectedly fast rate, according to research in Peru’s Cordillera Blanca.

They are currently shrinking by about one percent a year, and that percentage is increasing steadily, according to the calculations by McGill University doctoral student Michel Baraer.

But despite this accelerated glacial shrinking, for the first time, the volume of water draining from the glacier into the Rio Santa in Northern Peru has started to decrease significantly.


Baraer and his collaborators, professor Bryan Mark at Ohio State University and professor Jeffrey McKenzier at McGill, calculate that water levels during the dry season could decrease by as much as 30 percent lower than they are currently.

“When a glacier starts to retreat, at some point you reach a plateau and from this point onwards, you have a decrease in the discharge of meltwater from the glacier,” explains Baraer.

“Where scientists once believed that they had 10 to 20 years to adapt to reduced runoff, that time is now up,” says Baraer.

“For almost all the watersheds we have studied, we have good evidence that we have passed peak water.”

This means that the millions of people in the region who depend on the water for electricity, agriculture, and drinking water could soon face serious problems because of reduced water supplies.

Baraer presented the findings at the American Geophysical Union meeting last week; full findings appear in the Journal of Glaciology.

The research was funded by McGill’s department of Earth and planetary sciences, the National Science Foundation (USA), and Ohio State University.

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