‘Sleeping giant’ glacier may lift seas two metres: study

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Glacier

A rapidly melting glacier atop East Antarctica is on track to lift oceans at least two metres, and could soon pass a “tipping point” of no return, researchers said Wednesday.

To date, scientists have mostly worried about the Greenland and West Antarctic ice sheets as dangerous drivers of sea level rise.

But the new study, following up on earlier work by the same team, has identified a third major threat to hundreds of millions of people living in coastal areas around the world.

“I predict that before the end of the century the great global cities of our planet near the sea will have two- or three-metre (6.5 – 10 feet) high sea defences all around them,” said Martin Siegert, co-director of the Grantham Institute and Department of Earth Science and Engineering at Imperial College London, and the study’s senior author.

From the air, the contours of Totten Glacier — roughly the size of France — are invisible because the entire Antarctic continent is covered by a seamless, kilometres-thick blanket of snow and ice.

Geologically, however, it is a distinct — and volatile — beast.

– Disintegration accelerating –

Last year, Siegert and colleagues revealed that the underbelly of the glacier — most of which sits below sea level — is being eroded by warm, salty sea water flowing hundreds of kilometres inland after passing through underwater “gateways”.

As it does, the portion of the glacier resting on water rather than rock increases, accelerating the pace of disintegration.

The new study, published in Nature, used satellite data to map the hidden geological contours of the region.

The researchers found evidence that Totten similarly melted during an earlier period of natural global warming a few million years ago — a possible dress rehearsal for what is happening today.

“During the Pliocene epoch, temperatures were two degrees Celsius (3.6 degrees Fahrenheit) higher than they are right now, and CO2 levels in the atmosphere were 400 ppm,” or parts per million, Siegert said.

Sea levels during the Pliocene peaked at levels more than 20 metres (65 feet) higher than today.

“We are at 400 ppm right now, and if we do nothing about climate change we’re going to get 2C more warming too,” he added.

– Critical threshold –

Indeed, even when pledges by 195 nations to cut greenhouse gases — submitted ahead of the landmark Paris Agreement last December — are taken into account, temperatures are still set to increase an additional two degrees, The United Nations has said.

Other scientists not involved in the research said its findings should be a wakeup call.

“Totten Glacier is a slumbering giant,” said Andy Shepherd, Director of the NERC Centre for Polar Observation and Modelling at the University of Leeds in England.

The “strong evidence” that the glacier has been unstable in the past, coupled with signs that it is melting now, are “a clear warning that changes might be on the horizon,” he said.

Up to now, estimates of how much Antarctica will contribute to global sea level rise before 2100 have been conservative.

The latest report from the UN’s climate science panel put that number at about a dozen centimetres (five inches), all of it from a relatively small section of the West Antarctic Ice Sheet, which is itself 10 times smaller than East Antarctica.

The Intergovernmental Panel on Climate Change (IPCC) predicted that total sea level rise from all sources — expansion of warming water, glaciers, Greenland — would probably not top a metre.

But the low figure for Antarctica has more to do with gaps in knowledge than differences of opinion.

As recently as 2000, the IPCC forecast that East Antarctica would gain mass, a scenario that few scientists believe today.

Siegert’s greatest concern is that Totten Glaciers, and other massive ice bodies, “could cross a critical threshold within the next century, entering an irreversible period of very rapid retreat.”

The problem is that science is unable to say when that might happen — or if it has happened already.

“These are issues that we have to resolve in our society today,” he said by phone. “They are pressing right now.”

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  • Neo_kenyan

    Miguna correctly points out that he is not the ICC prosecutor but incorrectly asserts he is under no obligation to reveal the evidence he purports to hold. A lawyer is an officer of the court and has a duty to serve the public interest. Lawyers are ethically bound to serve others and devote their intellect and efforts to the public good. The public good/interest lies in the disclosure of evidence relating to the PEV. Miguna not only has the obligation to disclose this “information” but has a duty to do it. Failure to which, he violates his professional obligations. Professional ethics 101, Miguna

    • Francis

      Dude so if a lawyer knows his client is a THIEF s/he is supposed to tell the court-MY CLIENT IS A THIEF AND GUILTY AS CHARGED in order to help the court/serve public good? are you serious? go back to school.

  • Francis Muema

    Let’s not intimidate whistle blowers, would we rather he kept quiet? we should thank Miguna and encourage him to tell us more. If we mistreat him, other potential whistle blowers will keep the info to themselves.

    • kenyamoja

      whistle blowers have evidence remember githongo

  • bondoligawa

    Something is indeed wrong with Miguna, how can he chicken out after coming out with such Zeal? ODM’s Caroli has taken the right route, let Miguna be sued for in Law he is under obligation to respond failure of which wishes of the Plaintiff will carry the day.

  • LOVINGSTONE

    let MIGUNA make his stands perpendicular to tell Kenyans more about what he claims to know. Threats won’t help. The dilemma still stands ‘why now not then, 2008’

  • The push to have Miguna reveal what he knows about horrendous corruption and deception in PM’s office will bring down those who are asking for it. Only a fool goes for whats negative praying that it doesnt come out. Odm figures have been on a long mission of self-destruct and thats at hand already. What will happen if Miguna Miguna indeed co-operates with state security agencies? To establish the truth, folks dont forget every one mentioned will have to prove his or her own innocence. Desperate Illogical guys in Odm dont figure out what they are up against!

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