| Author |
Message |
zerega
Member
|
# Posted: 26 Nov 07 13:32 - Edited by: zerega
Reply
Scarlet asked how tall these ice pinnacles are:
 .
That depends.
Ice penitentes start as a solid glacier or snow field. At this location the slowly moving ice compound eats a part of the international road between Argentina and Chile every winter. Therefore a caterpillar has to cut through the glacier every spring to free this short stretch of road from its solid winter ice cover:
The lower ice pack cut off from the glacier is usually between 1.5 and 3 meters (5 to 10 ft) thick. At this altitude - more than 4000 meters high - and below freezing temperatures the sun starts to sublimate (not melt) the ice during the day. Some spots loose a bit more ice and start to form shallow pits. The bottom of the hollow receives more radiation than the walls each day ...
... leaving the walls mostly intact but making the dells grow deeper and deeper until they reach the plain earth at the bottom. Several pits may merge until some free standing blades remain oriented towards the general direction of the sun:
At this place the penitentes are about man's size, but can reach up to 6 meters (18ft) when grown out of larger ice or snow fields.
After just 3 months and about 4000 cars, the road will be covered again by the first snow of autumn. I made this panorama just two weeks away from the end of this summer season:
The first one to describe the penitentes was Charles Darwin when making an excursion into the Andes on his historic journey where he developed the idea of the evolution of species. He must be in good humour when naming the ice blades penitentes (those who perform the Catholic Sacrament of Penance and Reconciliation/Confession).
|
Oscar_
Moderator
|
# Posted: 26 Nov 07 13:56
Reply
Very interesting story about these beautiful pictures. Thanks for explaining these wonderful ice pinnacles, know I understand.
|
Steve L
Member
|
# Posted: 26 Nov 07 14:24
Reply
Thank you for the additional pictures and explanation. As Oscar said, “very interesting” to see and understand the formations and to have a better understanding of the true size of these ice pinnacles.
|
Dieuwertje
Member
|
# Posted: 26 Nov 07 17:19
Reply
Zarega, this is what I like so much of Woophy, a good explanation of what we see !
The story you told is very clear to understand and the photo's are wonderful.
|
devish
Member
|
# Posted: 26 Nov 07 19:01
Reply
Nice info and nice pictures, thanks zerega!
|
Paulo Calafate
Member
|
# Posted: 28 Nov 07 01:58
Reply
I love that pure white. Fantastic work. Congratulations
|
Martin de Rijk
Member
|
# Posted: 28 Nov 07 07:24
Reply
Fine explanation with beautiful pictures. Thanks zerega, a fine series to show at school :-)
|
Corneel Timmermans
Member
|
# Posted: 29 Nov 07 13:00
Reply
Hi,
Thx for the explanation, good story and marvellous photo's (again)
grtz
Corneel
|
scarlet
Member
|
# Posted: 1 Dec 07 20:05
Reply
Thanks for the explanation. They are even taller than I thought.
|
Online now: Guests - 2 Members - 0