31 Dec 2006 - 1 Jan 2007
We travelled to El Calafate, Argentina for the sole purpose of visiting the glacier which is about 70km outside of town. So on Dec 31, we visited Glacier Perito Moreno - stayed about 4 hours just watching the glacier. Moreno is unique in that it is one of few advancing glaciers in the world... Who thought watching ice melt could be so much fun? As you can (or cannot) see in the images, it is very very difficult to judge the size of the glaciers - if you look closely at the pictures, one has a flock of ibises flying above, and another has a boat in it.
After a few hours of glacial gawking, we found a nice campsite on a lake and Andrew fished - catching some long, but skinny trout - while a gorgeous double rainbow formed overhead. We drove through a valley certainly carved out by a glacier, where there were obvious glacier erratics (large rocks left behind by the glacier as it retreated).
On New Years day, we could not resist the magnetic forces of the glacier. . . back to Perito Moreno for another multi-hour viewing session - this time as the sun set through thick rainclouds. Just fascinating - SNAP! CRACKLE! POP! BOOM! Incredible sounds and sites as the glacier cracked and pieces fell into the lake below.
Can anyone identify this bird? (It resembles an eagle, but we have seen so many that it is hard to believe...)
Incidentally, a sign posted in several areas around the glacier stating "Take your trash back to El Calafate" has had us giggling nonstop since. Andrew imagines Gene Hackman in a bad Southern accent; me, I imagine Clint Eastwood, in his Dirty Harry days... "Why don´t you take your trash back to El Calafahteeehhh..."
The formation of glaciers (as per Wikipedia): "The snow which forms temperate glaciers is subject to repeated freezing and thawing, which changes it into a form of granular ice called névé. Under the pressure of the layers of ice and snow above it, this granular ice fuses into denser firn. Over a period of years, layers of firn undergo further compaction and become glacial ice. The distinctive blue tint of glacial ice is often wrongly attributed to Rayleigh scattering which is supposedly due to bubbles in the ice. The blue color is actually created for the exact same reason that water is blue, that is, its slight absorption of far red light due to an overtone of the infrared OH stretching mode of the water molecule. . . The lower layers of glacial ice flow and deform plastically under the pressure, allowing the glacier as a whole to move slowly like a viscous fluid. Glaciers usually flow downslope though they do not need a slope to flow, as they can be driven by the continuing accumulation of new snow at their source, creating thicker ice and a surface slope. The upper layers of glaciers are more brittle, and often form deep cracks known as crevasses or Bergshrunds as they move. Crevasses form due to internal differences in glacier velocity between two quasi-rigid parts above the deeper more plastic substrate far below. As the parts move at different speeds and directions, shear forces cause the two sections to break apart opening the crack of a crevass all along the disconnecting faces."
