Re: [asa] ESA: Wilkins Ice Shelf under threat

Media Hype on "Melting" Antarctic Ignores Record Ice Growth
http://tomnelson.blogspot.com/2008_10_12_archive.html
U.S. Senate Committee on Environment and Public Works - Minority Page

 The media is once again hyping an allegedly dire consequence of man-made
global warming. This time the media is promoting the ice loss of one tiny
fraction of the giant ice-covered continent and completely ignoring the
current record ice growth on Antarctica. Contrary to media hype, the vast
majority of Antarctica has cooled over the past 50 years and ice coverage
has grown to record levels since satellite monitoring began in the 1979,
according to peer-reviewed studies and scientists who study the area.
(LINK)

 Former Weather Channel Meteorologist Joe D'Aleo rejected the hype
surrounding the recent Wilkins Ice Shelf collapse in Western Antarctica. "The
shattered part of the Wilkins ice sheet was 160 square miles in area, which
is just 0.01% of the total current Antarctic ice cover, like an icicle
falling from a snow and ice covered roof," D'Aleo wrote on March 25. (LINK)
"We are very likely going to exceed last year's record [for Southern
Hemisphere ice extent]. Yet the world is left with the false impression
Antarctica's ice sheet is also starting to disappear," D'Aleo added.

Climate scientist Dr. Ben Herman, past director of the Institute of
Atmospheric Physics and former Head of the Department of Atmospheric
Sciences at the University of Arizona, stated, "It is interesting that all
of the AGW (anthropogenic global warming) stories concerning Antarctica are
always about what's happening around the [western] peninsula, which seems to
be the only place on Antarctica that has shown warming. How about the net
'no change' or 'cooling' over the rest of the continent, which is probably
about 95% of the land mass, not to mention the record sea ice coverage
recently."

Much more here:
http://ncwatch.typepad.com/media/2008/03/climate-confusi.html
Lynn

On Sat, Nov 29, 2008 at 1:05 PM, Rich Blinne <rich.blinne@gmail.com> wrote:

>
>
> http://www.esa.int/esaEO/SEMXK5AWYNF_planet_0.html
>
> 28 November 2008
> New rifts have developed on the Wilkins Ice Shelf that could lead to the
> opening of the ice bridge that has been preventing the ice shelf from
> disintegrating and breaking away from the Antarctic Peninsula.
>
> The ice bridge connects the Wilkins Ice Shelf to two islands, Charcot and
> Latady. As seen in the Envisat image above acquired on 26 November 2008, new
> rifts (denoted by colourful lines and dates of the events) have formed to
> the east of Latady Island and appear to be moving in a northerly direction.
>
> Dr Angelika Humbert from the Institute of Geophysics, Münster University,
> and Dr Matthias Braun from the Center for Remote Sensing, University of
> Bonn, spotted the newly formed rifts during their daily monitoring
> activities of the ice sheet via Envisat Advanced Synthetic Aperture Radar
> (ASAR) acquisitions.
>
> "These new rifts, which have joined previously existing rifts on the ice
> shelf (blue dotted line), threaten to break up the chunk of ice located
> beneath the 21 July date, which would cause the bridge to lose its
> stabilisation and collapse," Humbert explained. "These recent changes are
> happening slower and more continuously than the events we saw earlier this
> year."
>
> In February 2008 an area of about 400 km² broke off from the ice shelf,
> narrowing the ice bridge down to a 6 km strip. At the end of May 2008 an
> area of about 160 km² broke off, reducing the ice bridge to just 2.7 km.
> Between 30 May and 9 July 2008, the ice shelf experienced further
> disintegration and lost about 1 350 km².
>
> *The Wilkins Ice Shelf, a broad plate of floating ice south of South
> America on the Antarctic Peninsula, had been stable for most of the last
> century before it began retreating in the 1990s. The peninsula has been
> experiencing extraordinary warming in the past 50 years of** 2.5°C.*
>
> *If the ice shelf breaks away from the peninsula, it will not cause a rise
> in sea level since it is already floating. However, ice shelves on the
> Antarctic Peninsula are sandwiched by extraordinarily raising surface air
> temperatures and a warming ocean, making them important indicators for
> on-going climate change.*
>
> Long-term satellite monitoring over Antarctica is important because it
> provides authoritative evidence of trends and allows scientists to make
> predictions. Over the last 17 years, ESA's ERS and Envisat satellite
> missions have been the main vehicles for testing and demonstrating the use
> of Earth Observation data in Polar Regions.
>
>
> In the past 20 years, seven ice shelves along the Antarctic Peninsula have
> retreated or disintegrated, including the most spectacular break-up of the
> Larsen B Ice Shelf in 2002, which Envisat captured within days of its
> launch.
>
> Envisat's ASAR instrument is particularly suited to acquire images over
> Antarctica during the local winter period because it is able to produce
> high-quality images through bad weather and darkness, conditions often found
> in the area.
>
> Daily ASAR images of Antarctica are easily accessible to scientists. ESA
> will publish an update about the status of the Wilkins Ice Shelf in the
> event of a break-up.
>
>

To unsubscribe, send a message to majordomo@calvin.edu with
"unsubscribe asa" (no quotes) as the body of the message.
Received on Sat Nov 29 16:05:19 2008