Global Warming: Attenborough warns of ice shelf destruction in Antarctica

UK Naturalist and documentary maker David Attenborough has warned about the implications of climate change melting ice sheets in the polar regions but emphasised the changes under way in Antarctica "is likely to have the most dramatic effects of all".

His comments were made in a November 2011 article in the BBC Radio Times reported by the Independent newspaper. While the title of the Independent newspaper article - Warning over melting ice at North Pole - places emphasis on processes in the Arctic, the important statement by Attenborough is about the collapse of ice shelves fringing Antarctica and the implications for the West Antarctic Ice Sheet.

David Attenborough said "The meltwaters from Greenland's glaciers alone could cause a rise in global sea levels of up to half a metre by the end of this century,"

Attenborough visited both the Arctic and Antarctic in the making of the seven part series about planet Earth's cryosphere - Frozen Planet (BBC Frozen Planet website). The film team witnessed not only the melting of Arctic sea ice, but the calving of icebergs from glaciers in Greenland and Antarctica which contributes to sea level rise.

"It is the change to the permanent ice that fringes the coasts of Antarctica that is likely to have the most dramatic effects of all," Attenborough said.

If global warming leads to the collapse of the ice shelves in Antarctica, "vast quantities of land ice and meltwater will slide into the sea and cause a major rise in sea levels around the globe", he said.

"When that will happen and by how much are difficult questions. But with over half of the human population living near the coast, the answers may be only too devastating." concluded Attenborough.

There are already signs of the West Antarctic Ice Sheet (WAIS) losing ice mass. I reported on November 6, 2011 on Global Warming in Antarctica: Thwaites and Pine Island Glaciers accelerating, West Antarctic Ice Sheet losing mass.

Unfortunately the BBC decided to make the seventh episode of Frozen Planet optional for overseas networks to purchase and broadcast, valuing the income to be earned more than the message of the seventh episode. The seventh episode - Meltdown - details the changes happening in polar regions with global warming and the implications for polar wildlife, and the global climate change impacts.

You can read more about the Stability of the West Antarctic ice sheet in a warming world by Ian Joughin and Richard B. Alley, published 24 July 2011 in Nature Geoscience (doi:10.1038/ngeo1194)

An informative article on Earthsky by Dr Sophie Nowicki explains the concern with the Pine Island Glacier discharging ice from the West Antarctic Ice Sheet - Sophie Nowicki on weak underbelly of West Antarctic Ice Sheet

The following video, compiled by NASA/Goddard Space Flight Center Scientific Visualization Studio, shows glacier flow rates in the Amundsen Sea Embayment of West Antarctica accelerating and large changes in elevation occurring for the Thwaites, Pine Island and Smith glaciers.

Caption: This animation shows glacier changes detected by ATM, ICESat and ice bridge data in the highly dynamic Amundsen Embayment of West Antarctica. We know that ice speeds in this area have increased dramatically from the late 1990s to the present as the ice shelves in this area have thinned and the bottom of the ice has lost contact with the bed beneath. As the ice has accelerated, ice upstream of the coast must be stretched more vigorously, causing it to thin. NASA-sponsored aircraft missions first measured the ice surface height in this region in 2002, followed by ICESat data between 2002 and 2009. Ice Bridge aircraft have measured further surface heights in 2009 and 2010, and these measurements continue today. Integrating these altimetry sources allows us to estimate surface height changes throughout the drainage regions of the most important glaciers in the region.

We see large elevation changes at the coast on Thwaites glacier, at the center of the images, and large and accelerating elevation changes extending inland from the coast on Pine Island and Smith glaciers, to the left and right of the images, respectively. The changes on Pine Island and Smith glaciers mark these as potential continuing sources of ice to the sea, and they have been surveyed in 2011 by Ice Bridge aircraft and targeted for repeat measurements in coming years.

The scary part is that countries are already starting to quietly jostle for position for influence in the possible exploitation of Antarctic mining and biomass resources when the Protocol on Environmental Protection to the Antarctic Treaty comes up for review in 2041, fifty years after it came into effect in 1991. At the moment the environmental protocol of the treaty forbids "any activity relating to mineral resources, other than scientific research". But that doesn't stop the various nation states making claims and estblishing bases and research facilities to position their influence on the future of Antarctica. Read Andrew Darby's 2010 article on China flags its Antarctic intent.

Sources:

Comments

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

Whom to believe? A pop singer/politician or a scientist?

First we listen to Al Gore now it's David Attenborough a Politician and a TV man why not listen to them Takver, Just because they have no scientific qualifications (a bit like you Takver)they help push the lie of man made Global so they must know what they are talking about right?LOL
A paper to be published soon by the British Antarctic Survey in the journal Geophysical Research Letters is expected to confirm that over the past 30 years, the area of sea ice around the continent has expanded.
Last week, federal Environment Minister Peter Garrett said experts predicted sea level rises of up to 6m from Antarctic melting by 2100, but the worst case scenario foreshadowed by the SCAR report was a 1.25m rise.

Mr Garrett insisted global warming was causing ice losses throughout Antarctica. "I don't think there's any doubt it is contributing to what we've seen both on the Wilkins shelf and more generally in Antarctica," he said.

Dr Allison said there was not any evidence of significant change in the mass of ice shelves in east Antarctica nor any indication that its ice cap was melting. "The only significant calvings in Antarctica have been in the west," he said. And he cautioned that calvings of the magnitude seen recently in west Antarctica might not be unusual.

"Ice shelves in general have episodic carvings and there can be large icebergs breaking off - I'm talking 100km or 200km long - every 10 or 20 or 50 years."

http://www.news.com.au/antarctic-ice-is-growing-not-melting-away/story-0...

Now who should we believe? A Pop singer/Politician or a Scientist I know the Pop singer/Politician because he pushes the man made Global warming Lie LOL

Keep up the good work Takver and don't let facts get in the way of a good story

Science in that newspaperreport not inconsistent with my article

LOL, the science in that newspaper report is not inconsistent with my article. Let's examine the claims (greyed text is taken directly from the 2009 Australian news artice):

1. ICE is expanding in much of Antarctica, contrary to the widespread public belief that global warming is melting the continental ice cap. The results of ice-core drilling and sea ice monitoring indicate there is no large-scale melting of ice over most of Antarctica, although experts are concerned at ice losses on the continent's western coast."

I made no claims regarding the East Antarctic ice sheet, and whether it was increasing, stable or decreasing. I did make claims about the west antarctic ice sheet (WAIS) that this article, from 2009, appears to support.

2. Ian Allison said sea ice losses in west Antarctica over the past 30 years had been more than offset by increases in the Ross Sea region, just one sector of east Antarctica. "Sea ice conditions have remained stable in Antarctica generally," Dr Allison said.

I agree with Allison that Sea Ice conditions have remained stable. In fact my article wasn't about the extent of Antarctic sea ice. It was about the undermining of ice shelves, with receding grounding lines, accelerating flowrate of glaciers and mass loss of the West Antarctic Ice sheet through the glaciers.

3. Sea levels may rise with losses from freshwater ice sheets on the polar caps. In Antarctica, these losses are in the form of icebergs calved from ice shelves formed by glacial movements on the mainland.

Indeed, this is what is happening on the Antarctic peninsula and now West Antarctica.

4. Last week, federal Environment Minister Peter Garrett said experts predicted sea level rises of up to 6m from Antarctic melting by 2100, but the worst case scenario foreshadowed by the SCAR report was a 1.25m rise.

Yes, well I always thought Peter Garrett was a better musician than a politician. A 6m rise this century is an extraordinay claim to make. Either this was a poor remark by Garrett or he was seriously misquoted by the reporter. I note that this is not a direct quote - it may have been inaccurate reporting by the journalist.

5. Dr Allison said there was not any evidence of significant change in the mass of ice shelves in east Antarctica nor any indication that its ice cap was melting.

Yep, no disagreement here with Dr Allison regarding ice shelves in East Antarctica

6. "Ice shelves in general have episodic carvings and there can be large icebergs breaking off - I'm talking 100km or 200km long - every 10 or 20 or 50 years."

Agree with this statement, although I estimate with the warming southern ocean undermining ice shelves, that massive calvings of icebergs will happen slightly more often. A one in 20 year event might become a 1 in 10 event.

7. Australia's Davis Station in East Antarctica by the Antarctic Climate and Ecosystems Co-Operative Research Centre shows that last year, the ice had a maximum thickness of 1.89m, its densest in 10 years. The average thickness of the ice at Davis since the 1950s is 1.67m.

No dispute here either - East Antarctica is on a high plateau. Increased precipitation over East Antarctica is not inconsistent with global warming - in fact in general a warmer atmosphere can carry more water, so more precipitation (as rain or snow) is likely in some regions.

8. A paper to be published soon by the British Antarctic Survey in the journal Geophysical Research Letters is expected to confirm that over the past 30 years, the area of sea ice around the continent has expanded.

My article was not about sea ice extent. I haven't seen this paper, but from watching the NSIDC sea ice index I know that Antarctic sea ice has been fairly stable with a slight growth trend over past decades.

The Australian news article - Antarctic ice is growing, not melting away - is a wonderful piece of cherry picking the science to mislead you into thinking there is no problem with global warming and ice sheet loss in Antarctica. It quickly glazes over the scientific concern with West Antarctica and the Antarctic Peninsula and then concentrates on the scientific description of what is happening in the far more stable high plateau region of the East Antarctic Ice sheet. It ends with a reference to a 'forthcoming' scientific paper that sea ice is growing, without explaining why Sea Ice Extent is of far more concern in the Arctic than the Antarctic.

It is true that David Attenborough is not a climate scientist - he is a naturalist and documentary maker. He has a keen eye for observing the natural world. But I supported his statements with three pieces of recent climate science focussing on Antarctica which support Attenborough's statements:

All this in addition to the scientific sources in my previous article including the research of climatologists David Pollard and Robert M. DeConto. You can watch a 23 minute video of Pollard explaining past disintegration of the WAIS at the bottom of the article - Global Warming in Antarctica: Thwaites and Pine Island Glaciers accelerating, West Antarctic Ice Sheet losing mass

You can also checkout the wikipedia page on the West Antarctic Ice Sheet which contains many scientific references on the Potential collapse of the ice sheet.

Post new comment

The content of this field is kept private and will not be shown publicly.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Allowed HTML tags: <a> <em> <strong> <cite> <code> <ul> <ol> <li> <dl> <dt> <dd> <img> <p> <h2> <h3> <h4> <br> <code> <blockquote>
  • Lines and paragraphs break automatically.

More information about formatting options

CAPTCHA
This question is for testing whether you are a human visitor and to prevent automated spam submissions.
punctua_ion:

Events

sydney