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Sea level up 25m


Rob W
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Looks like a pretty good source to me peons  :D  :nufc:  :wub:

 

From todays "Indie"

 

Climate change: On the edge

Greenland ice cap breaking up at twice the rate it was five years ago, says scientist Bush tried to gag

By Jim Hansen

Published: 17 February 2006

 

A satellite study of the Greenland ice cap shows that it is melting far faster than scientists had feared - twice as much ice is going into the sea as it was five years ago. The implications for rising sea levels - and climate change - could be dramatic.

 

Yet, a few weeks ago, when I - a Nasa climate scientist - tried to talk to the media about these issues following a lecture I had given calling for prompt reductions in the emission of greenhouse gases, the Nasa public affairs team - staffed by political appointees from the Bush administration - tried to stop me doing so. I was not happy with that, and I ignored the restrictions. The first line of Nasa's mission is to understand and protect the planet.

 

This new satellite data is a remarkable advance. We are seeing for the first time the detailed behaviour of the ice streams that are draining the Greenland ice sheet. They show that Greenland seems to be losing at least 200 cubic kilometres of ice a year. It is different from even two years ago, when people still said the ice sheet was in balance.

 

Hundreds of cubic kilometres sounds like a lot of ice. But this is just the beginning. Once a sheet starts to disintegrate, it can reach a tipping point beyond which break-up is explosively rapid. The issue is how close we are getting to that tipping point. The summer of 2005 broke all records for melting in Greenland. So we may be on the edge.

 

Our understanding of what is going on is very new. Today's forecasts of sea-level rise use climate models of the ice sheets that say they can only disintegrate over a thousand years or more. But we can now see that the models are almost worthless. They treat the ice sheets like a single block of ice that will slowly melt. But what is happening is much more dynamic.

 

Once the ice starts to melt at the surface, it forms lakes that empty down crevasses to the bottom of the ice. You get rivers of water underneath the ice. And the ice slides towards the ocean.

 

Our Nasa scientists have measured this in Greenland. And once these ice streams start moving, their influence stretches right to the interior of the ice sheet. Building an ice sheet takes a long time, because it is limited by s

 

nowfall. But destroying it can be explosively rapid.

 

How fast can this go? Right now, I think our best measure is what happened in the past. We know that, for instance, 14,000 years ago sea levels rose by 20m in 400 years - that is five metres in a century. This was towards the end of the last ice age, so there was more ice around. But, on the other hand, temperatures were not warming as fast as today.

 

How far can it go? The last time the world was three degrees warmer than today - which is what we expect later this century - sea levels were 25m higher. So that is what we can look forward to if we don't act soon. None of the current climate and ice models predict this. But I prefer the evidence from the Earth's history and my own eyes. I think sea-level rise is going to be the big issue soon, more even than warming itself.

 

It's hard to say what the world will be like if this happens. It would be another planet. You could imagine great armadas of icebergs breaking off Greenland and melting as they float south. And, of course, huge areas being flooded.

 

How long have we got? We have to stabilise emissions of carbon dioxide within a decade, or temperatures will warm by more than one degree. That will be warmer than it has been for half a million years, and many things could become unstoppable. If we are to stop that, we cannot wait for new technologies like capturing emissions from burning coal. We have to act with what we have. This decade, that means focusing on energy efficiency and renewable sources of energy that do not burn carbon. We don't have much time left.

 

Jim Hansen, the director of the Nasa Goddard Institute for Space Studies in New York, is President George Bush's top climate modeller. He was speaking to Fred Pearce

96126[/snapback]

 

 

tl;dr

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"Right now, I think our best measure is what happened in the past. We know that, for instance, 14,000 years ago sea levels rose by 20m in 400 years - that is five metres in a century. This was towards the end of the last ice age, so there was more ice around. But, on the other hand, temperatures were not warming as fast as today."

 

5m in a century the man says .......................................

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Looks like a pretty good source to me peons  :nufc:  :wub:  :yes

 

From todays "Indie"

 

Climate change: On the edge

Greenland ice cap breaking up at twice the rate it was five years ago, says scientist Bush tried to gag

By Jim Hansen

Published: 17 February 2006

 

A satellite study of the Greenland ice cap shows that it is melting far faster than scientists had feared - twice as much ice is going into the sea as it was five years ago. The implications for rising sea levels - and climate change - could be dramatic.

 

Yet, a few weeks ago, when I - a Nasa climate scientist - tried to talk to the media about these issues following a lecture I had given calling for prompt reductions in the emission of greenhouse gases, the Nasa public affairs team - staffed by political appointees from the Bush administration - tried to stop me doing so. I was not happy with that, and I ignored the restrictions. The first line of Nasa's mission is to understand and protect the planet.

 

This new satellite data is a remarkable advance. We are seeing for the first time the detailed behaviour of the ice streams that are draining the Greenland ice sheet. They show that Greenland seems to be losing at least 200 cubic kilometres of ice a year. It is different from even two years ago, when people still said the ice sheet was in balance.

 

Hundreds of cubic kilometres sounds like a lot of ice. But this is just the beginning. Once a sheet starts to disintegrate, it can reach a tipping point beyond which break-up is explosively rapid. The issue is how close we are getting to that tipping point. The summer of 2005 broke all records for melting in Greenland. So we may be on the edge.

 

Our understanding of what is going on is very new. Today's forecasts of sea-level rise use climate models of the ice sheets that say they can only disintegrate over a thousand years or more. But we can now see that the models are almost worthless. They treat the ice sheets like a single block of ice that will slowly melt. But what is happening is much more dynamic.

 

Once the ice starts to melt at the surface, it forms lakes that empty down crevasses to the bottom of the ice. You get rivers of water underneath the ice. And the ice slides towards the ocean.

 

Our Nasa scientists have measured this in Greenland. And once these ice streams start moving, their influence stretches right to the interior of the ice sheet. Building an ice sheet takes a long time, because it is limited by s

 

nowfall. But destroying it can be explosively rapid.

 

How fast can this go? Right now, I think our best measure is what happened in the past. We know that, for instance, 14,000 years ago sea levels rose by 20m in 400 years - that is five metres in a century. This was towards the end of the last ice age, so there was more ice around. But, on the other hand, temperatures were not warming as fast as today.

 

How far can it go? The last time the world was three degrees warmer than today - which is what we expect later this century - sea levels were 25m higher. So that is what we can look forward to if we don't act soon. None of the current climate and ice models predict this. But I prefer the evidence from the Earth's history and my own eyes. I think sea-level rise is going to be the big issue soon, more even than warming itself.

 

It's hard to say what the world will be like if this happens. It would be another planet. You could imagine great armadas of icebergs breaking off Greenland and melting as they float south. And, of course, huge areas being flooded.

 

How long have we got? We have to stabilise emissions of carbon dioxide within a decade, or temperatures will warm by more than one degree. That will be warmer than it has been for half a million years, and many things could become unstoppable. If we are to stop that, we cannot wait for new technologies like capturing emissions from burning coal. We have to act with what we have. This decade, that means focusing on energy efficiency and renewable sources of energy that do not burn carbon. We don't have much time left.

 

Jim Hansen, the director of the Nasa Goddard Institute for Space Studies in New York, is President George Bush's top climate modeller. He was speaking to Fred Pearce

96126[/snapback]

 

Without bothering to read that is it safe to say it's pretty speculative and not necessarily the opinion of most scientists. :D

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Without bothering to read that is it safe to say it's pretty speculative and not necessarily the opinion of most scientists. wink.gif""

 

 

Just the American Assoc of Science, the Royal Society, The Geological Society NASA, .................................

 

Presumably your "scientists" are the ones at the Shitsville, Texas EXXON Center for AntiCommunist Science?

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Without bothering to read that is it safe to say it's pretty speculative and not necessarily the opinion of most scientists. wink.gif""

 

 

Just the American Assoc of Science, the Royal Society, The Geological Society  NASA, .................................

 

Presumably your "scientists" are the ones at the Shitsville, Texas EXXON Center for AntiCommunist Science?

96157[/snapback]

 

No, like the others I just couldn't be bothered to read it. Pretty bad I know, but it is Friday.

 

So when did you start accepting what NASA scientists say as the truth then Rob? :D

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Sleeping giant

 

"We are concerned because we know that sea levels have been able to rise much faster in the past - 10 times faster. This is a big gorilla. If sea level rise is multiplied by 10 or more, I'm not sure we can deal with that," co-author Eric Rignot, from the US space agency's (Nasa) Jet Propulsion Laboratory in California, told the BBC News website.

96101[/snapback]

 

I may be further from understanding global warming than I had previously suspected...

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Sleeping giant

 

"We are concerned because we know that sea levels have been able to rise much faster in the past - 10 times faster. This is a big gorilla. If sea level rise is multiplied by 10 or more, I'm not sure we can deal with that," co-author Eric Rignot, from the US space agency's (Nasa) Jet Propulsion Laboratory in California, told the BBC News website.

96101[/snapback]

 

I may be further from understanding global warming than I had previously suspected...

96179[/snapback]

 

:nufc:

 

What's the mechanism? How is a big gorilla involved?

 

king-kong-20051005025132783.jpg

 

Or just the worst metaphor/analogy ever? :D

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Whatever happens, I live at the top of a hill so I'm fine for the next century.  :wub:

96182[/snapback]

Unless the drains overflow again. :nufc:

96184[/snapback]

 

Ah that's merely a result of blocked sewage drains, nout to do with sea level. Unfortunately.

 

Hasn't blocked for ages now. Tempting fate there...

 

That's the downside of living where I live, we have our own sewage system or something and when it blocks you can smell what next door had for tea last night...

 

:D:yes

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Without bothering to read that is it safe to say it's pretty speculative and not necessarily the opinion of most scientists. wink.gif""

 

 

Just the American Assoc of Science, the Royal Society, The Geological Society  NASA, .................................

 

Presumably your "scientists" are the ones at the Shitsville, Texas EXXON Center for AntiCommunist Science?

96157[/snapback]

 

No, like the others I just couldn't be bothered to read it. Pretty bad I know, but it is Friday.

 

So when did you start accepting what NASA scientists say as the truth then Rob? :D

96165[/snapback]

 

 

I think it was their report on the "Challenger" disaster now you ask............ :nufc::wub::yes

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rate is estimated to ++5m per 100 years

 

which will still bugger a lot of E Anglia in your life times

 

and me caravan  at Newbiggin will be gone in MY lifetime   :yes  :yes  :nufc:  :rolleyes:

96080[/snapback]

 

Where's your source Rob, because tbh this sounds suprisingly like bull shit again! :nufc:

96097[/snapback]

 

5m per 100 years does sound like crap like. It's much quicker than any of the reports I've ever heard on global warming. Maybe Rob's been taken in by a rising sea level email scam. :wub:

96102[/snapback]

 

Reckon he's been watching 'The Day After Tomorrow' and thought he had the Discovery channel on? :D

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Whatever happens, I live at the top of a hill so I'm fine for the next century.  :D

96182[/snapback]

 

 

how high?

 

 

Are there any hills in Reading - always looks bloody flat to me??

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Whatever happens, I live at the top of a hill so I'm fine for the next century.  :D

96182[/snapback]

 

 

how high?

 

 

Are there any hills in Reading - always looks bloody flat to me??

96205[/snapback]

 

750ft above sea level where I am.

 

There's a big dip on the way down to Juntion 11 from my house.

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