Wednesday, 24 November 2010

... Patagonia: Glaciology 101

A mere 80 km away from El Calafate at Peninsula de Magallanes, is one of the planet's most dynamic and stunning ice fields. Layers of ice sculpted by the elements and then cracked & split by immense pressure, the raw magnificence of a glacier is something that has to be seen. And today I did just that.

Glaciar Perito Moreno is a 250 km2 ice formation that is 30 km in length, 5 km wide, 60 m high and boasts being the world's third largest reserve of fresh water. What actually makes it exceptional in the ice world is its constant advance (up to 2 m daily) with huge building-sized icebergs calving & collapsing into the Canal de los Tempanos. On the rare chance that you might not get to see this occur then you will certainly hear it. Your visit is not only a visual experience of amazing shapes and colours but also auditory. Calving of glaciers is often preceded by a loud cracking or booming sound.

The glacier formed as the moisture-laden Pacific storms turned into snow over the accumulation area. This eventually compacted as ice which ran like a river thanks to the wonder than is gravity. See! Not just for apples. As the ice river surged downhill, melted ice mixed with rock and soil grinding that into a lubricant. This in turn kept the glacier moving along and also caused the formation of moraines & crevasses. 

A series of catwalks and lookout points allow you bring a  to see and hear the glacier. You can even bring a picnic - just remember that what you bring into the National park you must take out with you.

Boat trips allow you to get up close and personal with Moreno. Well as close as they can for it to still be safe. You will still get a sense of the magnitude of this ice beast. Boats mimicking sardine cans leave from Puerto Bajo de las Sombras. I suspect it fills up like that because it is the first dock you see upon entering the park. A far better idea (and resulting in way better views in my humble opinion) is to get there before the big bus loads arrive, do the catwalk (and shake your little tush on it if you do so desire) and then take a far less crowded boat from the other side to go view the north face of the glacier. Both boat trips run for an hour anyway so really it depends on how intimate you wish to get with an absolute stranger. It was quite simply the best AR$50 I've spent. Several times bits of the glacier collapsed in an explosion of ice and it was absolutely amazing to watch. When the glacier carves into the lake, its "glacial flour" of ground up rock gives the water a milky colour. When the sun's light is diffracted off unsettled sediment a stunning array of turquoise, pale mint and azure are created.

Another fascinating sight of this glacier is its hue. There were some absolutely beautiful shades of blue here too. These are caused by wavelengths and air bubbles. The bluer the ice the longer the path light has to travel caused by the ice being more compacted. In the uncompacted areas, air bubbles absorb long wavelengths of white light so what you see is white.

Nothing could have prepared me for the sheer force witnessed today. The sight and sound of ice falling so hard is something I'll always remember. I doubt that few places on this planet could offer the same speech-stopping encounter.......


No comments:

Post a Comment