NASA: Antartica - Breakup Continues on the Wilkins Ice Shelf - 02.06.13
Posted by Ricardo Marcenaro | Posted in NASA: Antartica - Breakup Continues on the Wilkins Ice Shelf - 02.06.13 | Posted on 18:11
An ice shelf is a thick plate of ice
attached to a coastline on one side and floating over the ocean on the
other side. Many ice shelves fringe Antarctica, including the Wilkins
Ice Shelf on the Antarctic Peninsula, which underwent a series of
breakup events in 1998, 2008, and 2009.
Just as earthquakes can sometimes leave landscapes more prone to
future quakes, the breakups on the Wilkins Ice Shelf left it vulnerable
to further disintegration. In addition, the sea ice that had long
pressed the shelf up against the coastline moved out, putting the
remnants of the shelf in direct contact with open water. Ocean waves
went to work on the ice, and in early 2013 the fracturing continued.
Acquired March 23, 2013, this high-resolution image from the WorldView-2
satellite shows a portion of the Wilkins Ice Shelf and a large
assemblage of icebergs and sea ice just off the shelf front. (Image
copyright 2013 DigitalGlobe, Inc.)
Some of the iceberg surfaces give clues that they recently broke off
from the shelf: many are somewhat lighter in color than the nearby sea
ice, and some bear the same surface features as those seen on the shelf,
including melt pond scars (which appear in pale blue). Melt pond scars
are areas where meltwater once pooled on top of the ice and then
refroze.
Ted Scambos
of the National Snow and Ice Data Center has followed the effects of
rising temperatures on the ice shelves of the Antarctic Peninsula, but
he does not attribute this most recent breakup to global change. “I
would not characterize this breakup as a direct result of climate
warming, but rather an indirect result of the change in the shape of the
shelf,” he states. “A breakup changes the stresses within the ice and
will cause small retreats that reshape the shelf for several years.
These retreats tend to happen when ocean waves can impinge directly on
the shelf front.”
Clouds frequently obscure satellite views of the polar regions, so
pinning down the precise date of this breakup event is difficult.
Scambos suspects that the latest fragmentation of the Wilkins Ice Shelf
occurred in mid-March 2013.
Image Copyright 2013 DigitalGlobe, Inc. and courtesy Paul Morin and William Risse, Polar Geospatial Center. Caption by Michon Scott with information from Ted Scambos, National Snow and Ice Data Center.
- Instrument:
- DigitalGlobe - WorldView-2
Ricardo M Marcenaro - Facebook
Blogs in operation of The Solitary Dog:
Solitary Dog Sculptor:
byricardomarcenaro.blogspot
Solitary Dog Sculptor I:
byricardomarcenaroi.blogspot.com
Para:
comunicarse conmigo,
enviar materiales para publicar,
propuestas comerciales:
marcenaroescultor@gmail.com
For:
contact me,
submit materials for publication,
commercial proposals:
marcenaroescultor@gmail.com
My blogs are an open house to all cultures, religions and countries. Be a follower if you like it, with this action you are building a new culture of tolerance, open mind and heart for peace, love and human respect.
Thanks :)
Mis blogs son una casa abierta a todas las culturas, religiones y países. Se un seguidor si quieres, con esta acción usted está construyendo una nueva cultura de la tolerancia, la mente y el corazón abiertos para la paz, el amor y el respeto humano.
Mis blogs son una casa abierta a todas las culturas, religiones y países. Se un seguidor si quieres, con esta acción usted está construyendo una nueva cultura de la tolerancia, la mente y el corazón abiertos para la paz, el amor y el respeto humano.
Gracias:)
Comments (0)
Publicar un comentario