Global Warming is it Hype?

[bestsynd]

Is global warming real or is it just a natural process the Earth goes through?

The Arctic thawing threatens Russian village as water rise.  The village of Bykovsky population 457 is seeing the northeast coast being sucked into the ocean at the rate of 15 to 18 feet a year.

It is predicted at this rate that homes will be lost and possibly Bykovsky will be submerged underwater in time.

[aliaslezarddagain]

[Fnord Fred]

We really don't know enough to say either way; we only have accurate weather data from the last 200 years or so, a laughably insignificant portion of the total weather cycle the earth is believed to go through.

[Nictoe]

No Escape: Thaw Gains Momentum


The Big Melt

October 25, 2005

By ANDREW C. REVKIN

In 1969 Roy Koerner, a Canadian government glaciologist, was one of four men (and 36 dogs) who completed the first surface crossing of the Arctic Ocean, from Alaska through the North Pole to Norway.

Now, he said, such a trek would be impossible: there is just not enough ice. In September, the area covered by sea ice reached a record low. "I look on it as a different world," Dr. Koerner said. "I recently reviewed a proposal by one guy to go across by kayak."

At age 73, Dr. Koerner, known as Fritz, still regularly hikes high on the ancient glaciers abutting the warming ocean to extract cores showing past climate trends. And every one, he said, indicates that the Arctic warming under way over the last century is different from that seen in past warm eras.

Many scientists say it has taken a long time for them to accept that global warming, partly the result of carbon dioxide and other heat-trapping gases in the atmosphere, could shrink the Arctic's summer cloak of ice.

But many of those same scientists have concluded that the momentum behind human-caused warming, combined with the region's tendency to amplify change, has put the familiar Arctic past the point of no return.

The particularly sharp warming and melting in the last few decades is thought by many experts to result from a mix of human and natural causes. But a number of recent computer simulations of global climate run by half a dozen research centers around the world show that in the future human influence will dominate.

Even with just modest growth in emissions of the greenhouse gases, almost all of the summer sea ice is likely to disappear by late in the century. Some of the simulations, including those run on an advanced model at the National Center for Atmospheric Research in Boulder, Colo., show much of the summer ice disappearing by 2050, said Marika Holland, a scientist there who is working on the sea-ice portion of that model.

Of the various simulations, all done for an international scientific report on climate trends to be issued in 2007, the only ones that retain much summer sea ice in the Arctic by 2100 are those that assume global greenhouse-gas emissions are held constant at rates measured in 2000 - something that only five years later is already impossible.

The other models all produce an Arctic Ocean in summer akin to the "open polar sea" that was sought by oceanographers and explorers in the mid-1800's. "There would definitely be shipping along the Eurasian coast, and the polar bears would have some serious issues," Dr. Holland said.

The models are, of course, impressionistic views of a far more complicated Arctic reality, so their projections are uncertain. But what worries field scientists, who form their opinions based on empirical clues embedded in ice or recorded by thermometers, is that observations of change and evidence pointing to past patterns are agreeing with the models.

David Barber, an Arctic expert at the University of Manitoba, said emissions needed to be cut quickly to avert even greater damage. Skeptics who use the uncertainties to justify delaying such actions forget that uncertainty cuts both ways, and things could be far worse than forecast, Dr. Barber and others say.

"I wish we would have started 50 years ago, but to not start now would be a real tragedy," Dr. Barber said.

But, he added, it is important to accept that shrinking summer sea ice over the next century is inevitable and that humans need to adapt.

That inevitability presents a sticky problem for environmental groups, many of which have suggested that cutting greenhouse gases could save the polar bear and Eskimo traditions, both dependent on sea ice.

"Even if you would stop every engine right now, there is no escape unless you physically take the CO2 out of the air again," said Henk Brinkhuis, an expert on past Arctic ecosystems at Utrecht University in the Netherlands. He added that this would have to be done on a vast scale, far beyond simply planting trees or the like.

"You may argue for a long time whether this process will take 20, 50 or 100 years, but it doesn't change the fact that it will happen," Dr. Brinkhuis said.

A Work in Progress

The emerging picture of great Arctic changes ahead comes from the interlaced efforts of the modelers in their climate-controlled computer rooms and field scientists with numb toes and frosted beards. It will long remain a work in progress. But the underlying trends are robust, many Arctic scientists say.

Field work suggests that past Arctic warm spells, like a stretch through the 1920's and 1930's, were limited to certain regions, while the recent warming has largely progressed in concert with rising temperatures around the Northern Hemisphere - a sign of large forces at work, climate scientists say, not regional variability.

Field studies have also provided information on how energy flows from air to ocean and into melting ice, how melting ice freshens water and growing ice makes it saltier - all dynamics that have helped modelers refine their programs.

Recent expeditions on icebreakers have started building the first detailed picture of the communities of algae, plankton, small cod, seals and polar bears that form an ice-based ecosystem as tenuous as the ice itself.

In the virtual Arctic of computer simulations, thousands of lines of computer code mimic how ice, oceans and the atmosphere interact and are components of larger global models of earth's climate and oceans.

The models are the only way to test how the planet may react to various human actions. Because there is only one earth, there are no other options for such studies, given that the real earth is already well along in an unintended experiment - the rapid buildup of long-lived greenhouse gases.

Those who work in that realm have steadily improved their simulations. A decade ago, for instance, most depicted sea ice just as static reflective slabs, and almost all now replicate how ice is tugged by wind and ocean currents, Dr. Holland said.

The inevitability of summer ice retreats, she and other Arctic experts say, is a result of the nature of the climate system, which is something like a heavy flywheel. Once started, flywheels tend to keep going. Within a few decades, say many scientists focused on the region, the insulating power of greenhouse gases will dominate natural climate fluctuations, possibly for centuries.

And the flywheel in the Arctic moves faster than in other areas because the region amplifies change. The most obvious mechanism is the difference in how bright white sea ice and the dark sea act under sunlight. Ice reflects most of the solar energy striking it back into space. Water absorbs most of it.

A result is that each area of ocean exposed by melting ice soaks up heat, melting more ice, exposing more sea, soaking up even more heat - and so on, until the annual marathons held each spring on the floating ice near the North Pole are replaced by boat races.

Saving Greenland

Warming has already caused anger and confusion among native peoples on one hand and enthusiasm for new shipping routes among entrepreneurs on the other. But scientists are still grappling to describe what is going on. "You might call it the temperatization of the Arctic; we haven't really invented a word for it yet," said Charles Vörösmarty, the director of the Complex Systems Research Center at the University of New Hampshire and one of 21 co-authors of a recent article in Eos, a journal of the American Geophysical Union, about the changes.

The article grew out of several gatherings of Arctic scientists organized by the National Science Foundation over the last two years.

Titled simply "Arctic System on Trajectory to New, Seasonally Ice-Free State," it says, "There seem to be few, if any, processes or feedbacks within the Arctic system that are capable of altering the trajectory."

Those authors and many other experts have settled on the same picture of the region late this century: tundra retreats and forests spread; most sea ice disappears in late summer; coastlines wear away under the assault of wind-driven waves on waters that previously were sheathed in ice; permafrost turns to bogs; and ancient lakes that once sat atop permanently frozen ground drain like unplugged bathtubs.

Climatologists say the effects eventually could extend far beyond the sparsely populated north, contributing to climate and ocean shifts that could dry the American West and possibly slow north-flowing warm currents in the Atlantic Ocean that keep northern Europe milder than it would otherwise be.

The effects could also include a sharp increase in the rate at which seas are swelled by melting glacial ice and far greater warming as even more greenhouse gases, locked in permafrost and the Arctic seabed, are liberated by warming.

For example, American and Russian scientists studying lakes in northeastern Siberia recently reported that the melt of permafrost is generating methane, a potent greenhouse gas. In spots, so much methane is being released that roiling streams of bubbles prevent the surface from freezing even in the depths of the Siberian winter.

The most that can be expected, some climate scientists say, is to limit the human contribution to warming enough to forestall the one truly calamitous, if slow motion, threat in the far north: the melting of Greenland's ice cap.

Rising two miles high and spreading over an area twice the size of California, this vast reservoir - essentially the Gulf of Mexico frozen and flipped onto land - contains enough water to raise sea levels worldwide more than 20 feet.

In recent years, the ice sheets of Greenland have been building in the middle through added snowfall but melting even more around the edges in summer. Many Greenland experts say the melting is already winning out.

James E. Hansen, a scientist for the National Aeronautics and Space Administration who has been designing simulations of earth's climate for nearly four decades, is among those who say prompt cuts in emissions can avert a Greenland meltdown.

Dr. Hansen said that while the Arctic's amplifying effects, like the transition from white ice to dark water, are substantial, they still occur only when the region is feeling some big external warming influence, like the transport of heat from the rest of a greenhouse-warmed planet.

If prompt action is taken to slow growth in carbon dioxide releases, and other, easier efforts are begun to cut emissions of methane, soot and other sources of warming, he said, then it may be possible to retain some summer sea ice and prevent rapid deterioration of the Greenland ice sheet.

"It is physically and technologically possible, but there has to be a will to achieve it," Dr. Hansen said.

Other scientists are not as optimistic.

Fresh studies of ancient glacial ice and sea-floor sediments show that, if anything, the computer simulations projecting strong warming and ice retreats in the region over the long run may be substantial underestimates, Dr. Brinkhuis said.

"Everything we are seeing shows things can move more and faster than we think," he added, referring to geologic and glacial records of past Arctic changes.

The current increase in greenhouse gases, he continued, is similar to past natural changes that profoundly altered the world.

"We have not seen such fast carbon dioxide rises as we have now other than in extreme cases in the past," Dr. Brinkhuis said, including periods like one about 50 million years ago that turned the Arctic Ocean into a warm, weed-covered lake.

Confounding Turbulence

Dr. Brinkhuis and many other veteran Arctic researchers caution that there is something of a paradox in Arctic trends: while the long-term fate of the region may be mostly sealed, no one should presume that the recent sharp warming and seasonal ice retreats that have caught the world's attention will continue smoothly into the future.

"The same Arctic feedbacks that are amplifying human-induced climate changes are amplifying natural variability," explained Asgeir Sorteberg, a climate modeler at the Bjerknes Centre for Climate Research in Bergen, Norway.

Indeed, experts say, there could easily be periods in the next few decades when the region cools and ice grows.

The natural Arctic variability is shaped by basic geography and physics.

Near the Equator, climate is as predictable as the age-old trade winds that blow there, fueled by steady streams of sunlight and shaped by the planet's rotation. But toward the poles - and particularly the North Pole - everything gets stirred up, said David Atkinson, an atmospheric scientist at the International Arctic Research Center of the University of Alaska at Fairbanks.

The region has just about the most turbulent climate on earth, he said, one in which conditions are shaped by slow cycles of temperature changes in the Pacific Ocean, pulsing shifts in areas of high and low barometric pressure over the pole and North Atlantic, and fundamentally chaotic flutters in the atmosphere.

The North Pole climate is even more variable than that at the other end of the earth in part because the Northern Hemisphere is a mix of continents and islands topped by the small but dynamic Arctic Ocean, which is partly ice covered.

The Southern Hemisphere is mostly ocean with a permanently ice-sheathed continent at the pole.

Because of that natural turbulence, a significant camp of Arctic specialists say they are not convinced that humans are driving the changes in the North.

"It's definitely true that the level of variability in high-latitude regions is huge, and trying to separate this from a human-induced trend is very difficult," said Igor Polyakov, another expert at the school's Arctic research center.

In the short run, the natural fluctuations will most likely sustain those on both sides of the debate over how to respond to global warming, with cool years embraced by skeptics and hotter ones by proponents of cutting the heat-trapping gases, said Dr. Richard B. Alley, a geoscientist at Pennsylvania State University.

But he and other scientists say it is clear that in the long run, the Arctic will get warmer, a conclusion at the heart of the Arctic Climate Impact Assessment, a report commissioned by the eight Arctic nations and released last year.

Dr. Koerner, the Canadian glaciologist, pointed out on time scales of millenniums, the recent warming has even trumped a long cooling trend.

"The warming trend is even more significant," he said, "because it's not on a flat background but something that maybe should be getting colder."

For now, the modelers and field researchers continue to work at least in parallel, if not in tandem.

For example, Dr. Holland, a modeler, has never seen the real Arctic. She said a colleague who spends most summers slogging through ponds of meltwater on Arctic Ocean floes recently proposed creating a program called "Take a Modeler to the Arctic." The proposal was only half in jest, she said.

Just two weeks ago, she and that researcher, Donald Perovich, renewed the discussion, with fewer chuckles.

"I'd like to see what it's like before it actually disappears," Dr. Holland said.

Craig Duff contributed reporting from Churchill, Manitoba, for this article.
[/b]

[Guest]

Shameless plug:

http://bestsyndication.com/2005/Nicole-WILSON/102205-Melting_Ice_Floods_Arctic.htm

The Arctic thawing threatens Russian village as water rise. The village of Bykovsky population 457 is seeing the northeast coast being sucked into the ocean at the rate of 15 to 18 feet a year.

It is predicted at this rate that homes will be lost and possibly Bykovsky will be submerged underwater in time.

There are approximately four million people that live in the Arctic Circle region. The changing climate offers new opportunities with warmer weather, but at the same time they are under watch for the ocean waters rising. This will not only affect the homes but also the wilderness and way of life that this culture has known.

There have been new discoveries of petroleum fields in the Barents and Kara Seas due to the defrosting ice. There are concerns with the new oil industries polluting the environment that has been left alone. The melting of the permafrost layer threatens the foundations of nearly 20 percent of Russian homes, factories and pipelines. It poses a difficult situation for engineers in attempts to prevent building losses.

Not only is Russia affected, but Alaska also has its problems related to this defrosting ice. The United States is in preparation to relocate several Inuit villages at a cost of $100 million for each village.

Global warming is no longer a speculation as now there is measurable differences of the environment that is now being seen. It is not just the Arctic that is affected, but the whole world. Concerns in Africa have arouse due to a one degree Fahrenheit increase in temperature for the last 1000 years with 2005 possibly being even hotter.

[Nictoe]

New Study Warns of Total Loss of Arctic Tundra

November 1, 2005
By ANDREW C. REVKIN

If emissions of heat-trapping gases continue to accumulate in the atmosphere at the current rate, there may be many centuries of warming and a near-total loss of Arctic tundra, according to a new climate study.

Over all, the world would experience profound transformations, some potentially beneficial but many disruptive, and all at a pace rarely seen in nature, said the authors of the study, being published today in The Journal of Climate.

"The question is no longer whether we will need to address this problem, but when we will need to address the problem," said Kenneth Caldeira, an author of the study and a climate expert at the Carnegie Institution's Department of Global Ecology, based at Stanford University.

"We can either address it now, before we severely and irreversibly damage our climate, or we can wait until irreversible damage manifests itself strongly," Dr. Caldeira said. "If all we do is try to adapt, things will get worse and worse."

The paper's lead author, Bala Govindasamy of the Energy Department's Lawrence Livermore National Laboratory, said it might take 20 or 30 years before the scope of the human-caused changes becomes evident, but from then on there is likely to be no debate.

The researchers ran a computer model that simulates both the climate system and the flow of heat-trapping carbon into the air in the form of carbon dioxide, then back into soils and the ocean.

Most simulations of the potential human impact on climate have been confined to studying the next 100 years or so, but in this case the scientists started the calculations in 1870 and let the computers churn away through 2300.

The authors stressed that the uncertainties were high over such a time span, and said the study was intended to illustrate broad consequences rather than project specific ones.

They programmed the model to run as if the atmospheric concentration of carbon dioxide rose about 0.45 percent a year through 2300. That is slightly less than the current rate, about 0.5 percent.

In the simulation, the concentration of carbon dioxide doubles from pre-industrial levels in 2070, triples in 2120, and quadruples in 2160.

The results are sobering, Dr. Caldeira and other climate experts said, because the computer model used in this study tends to produce less warming from a greenhouse-gas buildup than many of the other climate simulations being run by other research teams.

It also presumes that plants and the ocean will continue to sop up carbon dioxide in the future, limiting the amount retained in the atmosphere. Many other independently developed models calculate that at some point, chemical and biological shifts caused by warming would reverse that flow and cause even more greenhouse gases to flood into the atmosphere.

Consistent with many other studies, the model showed that the Arctic would see the most warming, with average annual temperatures in many parts of Arctic Russia and northern North America rising more than 25 degrees Fahrenheit around 2100.

Antarctica would follow suit later, with temperatures there rising sharply around 2200.

The impact on vegetation and landscapes would transform large areas of the earth.

In the simulation, at least one ecosystem, the scrubby Arctic tundra largely vanishes as climate zones shift hundreds of miles north. Tundra would decline from about 8 percent of the world's land area to 1.8 percent.

Alaska, in the model, loses almost all of its evergreen boreal forests and becomes a largely temperate state.

But vast stretches of land that were once locked beneath permanent ice cover would open up. The area locked beneath ice would diminish to 4.8 percent of the planet's total land area, from 13.3 percent.

Several climate scientists not associated with the study said its main benefit was akin to the murky visions of possible futures experienced by Ebenezer Scrooge in "A Christmas Carol."

"It's a cautionary tale," said Gerald A. Meehl, a climate modeler at the National Center for Atmospheric Research in Boulder, Colo., who has conducted similar studies.

"The message is not to give up because the changes appear overwhelming, but instead the message should be the longer we wait to do something, the worse the consequences."

[Nictoe]

Climate 'warmest for millennium'

By Paul Rincon
BBC News science reporter

The last 100 years is more striking than either the Medieval Warm Period or Little Ice Age
Timothy Osborn, UEA
In the late 20th Century, the northern hemisphere experienced its most widespread warmth for 1,200 years, according to the journal Science.
The findings support evidence pointing to unprecedented recent warming of the climate linked to greenhouse emissions.

University of East Anglia researchers measured changes in fossil shells, tree rings, ice cores and other past temperature records or "proxies".

They also looked at people's diaries from the last 750 years.

Timothy Osborn and Keith Briffa of UEA analysed instrument measurements of temperature from 1856 onwards to establish the geographic extent of recent warming.

Then they compared this data with evidence dating back as far as AD 800.

The analysis confirmed periods of significant warmth in the Northern Hemisphere from AD 890 - 1170 (the so-called "Medieval Warm Period") and for much colder periods from 1580 - 1850 (the "Little Ice Age").

Natural records

The UEA team showed that the present warm period is the most widespread temperature anomaly of any kind since the ninth century.

"The last 100 years is more striking than either [the Medieval Warm Period or Little Ice Age]. It is a period of widespread warmth affecting nearly all the records that we analysed from the same time," co-author Timothy Osborn told the BBC.

Osborn and Briffa used 14 sets of temperature records from different locations across the Northern Hemisphere.

The records included long life evergreen trees growing in Scandinavia, Siberia and the Rockies which had been cored to reveal the patterns of wide and narrow tree rings over time. Wider rings related to warmer temperatures.

The chemical composition of ice from cores drilled in the Greenland ice sheets revealed which years were warmer than others.

Dear diary

The researchers used proxy data developed from the diaries of people living in the Netherlands and Belgium during the past 750 years that revealed, for example, the years when the canals froze.

"These records extend over many centuries and even thousands of years. We simply counted how many of those records indicated that, in any one year, temperatures were warmer than average for the region they came from," said Dr Osborn.

Professor John Waterhouse, director of the Environmental Sciences Research Centre Anglia Ruskin University in Cambridge commented: "Although we're getting increasingly accurate measurements of present-day temperature, we've got nothing like that from the past to compare those with.

"There's much uncertainty in past reconstructions. You've got to look at the reconstructed data in the past in light of the likely errors that those data have."

But he added: "As we get more and more evidence in, it is looking as if the current period is the warmest for over 1,000 years."

In November, Science published a paper showing atmospheric levels of the greenhouse gases carbon dioxide and methane are higher now than at any time in the past 650,000 years.

[Anti War]

I think the government should start forcing car companies to make more fuel efficient cars. Give more money for solar and wind too.
_________________
It's time to get out of Iraq

[GOODave]

[Betty Nice]

[US first]

[Betty Nice]

It's going to cost a lot more in the long run when we try to combat it's effects again. It burns dirty, in a couple of years that sh*t gonna be visible in the atmosphere. Money is going to be spent trying to find different ways to use alternative methods, there will most likely be stricter car exhaust regulations....that we as vehicle users will pay in order to pass smog on our vehicles. We're going backwards in time!
_________________

[Jaded]

[Nictoe]

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 snowfall. 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

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 snowfall. 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

http://news.independent.co.uk/environment/article345926.ece

[Nictoe]

Seasonal surface melt extent on the Greenland Ice Sheet has been observed by satellite since 1979 and shows an increasing trend. The melt zone, where summer warmth turns snow and ice around the edges of the ice sheet into slush and ponds of meltwater, has been expanding inland and to record high elevations in recent years.

NASA Climatologist, Dr. Hansen, warns of Explosive Ice Cap Collapse

Posted by Knightrider on February 6, 2006

Dr. Jim Hansen is causing waves again; and it's likely why Bush doesn't want his feet wet, when it reaches the steps of the WH. Hansen warns of a catastrophic collapse of the Greenland ice cap. But whether these changes occur within 20, 50, 100 years or more, it's clear that Bush and the GOP have deliberately ignored the long term impact and security threats from a global meltdown to the United States. As such, they are incompetent to ensure America's future security and are negligent to our future generation.

Unfortunately, our next generation(s) will aleady be swamped with the tsunami-sized US deficit, so why should they even suffer more economic losses to our agricultural, fishing and coastal trade industries? This the real outcome of Bush's Globalisation Policies-- is the submersion of US coastal communities and cities under 20 feet of water. As Clark discussed on his blog several months ago, global climate change is a national security threat issue that Dems should rally together on common ground for America.


Top climatologist forecasts swift ice cap collapse

THE Greenland ice cap could collapse many times faster than forecast, the US government's top climate modeller has warned.

On Monday, the UK government released a report saying that climate change was close to a "tipping point" that could trigger the ice sheet's collapse over the next thousand years, causing sea level to rise by seven metres worldwide. It suggests that the melting would follow a wave of warmth pushing through the 3-kilometre thick ice.

In a recent interview with New Scientist, Jim Hansen, the director of NASA's Goddard Institute for Space Studies, said the collapse of the ice sheet could be "explosively rapid", with sea levels rising "a couple of metres this century, and several more next century".

Hansen, who last week claimed that NASA was trying to gag him from making such predictions, says scientists have already spotted meltwater pouring down crevasses to the bottom of the ice sheet, where it could provide lubrication for huge swathes of ice to slip into the ocean.

From issue 2537 of New Scientist magazine, 04 February 2006
http://www.newscientist.com/channel/earth/mg18925373.900
Other interesting conclusions and assessments from the UK Report...

SNIP> "As the Arctic is warming faster than the planetary average, a local warming of 2.7C may equate to a global warming of only about 1.5C, which some climate scientists believe is certainly going to happen whatever policies are now set in train. ...."


SNIP> "Above a one degree Celsius increase, risks increase significantly, often rapidly for vulnerable ecosystems and species," concludes Bill Hare from the Potsdam Institute of Climate Impact Research in Germany, who produced an overview of more than 70 studies of impacts on water resources, agriculture and wildlife.

"In the one to two degree range, risks across the board increase significantly, and at a regional level are often substantial," he writes.

"Above two degrees the risks increase very substantially, involving potentially large numbers of extinctions or even ecosystem collapses, major increases in hunger and water shortage risks as well as socio-economic damages, particularly in developing countries."

A rise of 2C, the report suggests, will be enough to cause:

decreasing crop yields in the developing and developed world
tripling of poor harvests in Europe and Russia
large-scale displacement of people in north Africa from desertification
up to 2.8bn people at risk of water shortage
97% loss of coral reefs
total loss of summer Arctic sea ice causing extinction of polar bear and walrus
spread of malaria in Africa and north America
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The Big Thaw: Global Disaster Will Follow If the Ice Cap on Greenland Melts
Now scientists say it is vanishing far faster than even they expected.
by Geoffrey Lean

Greenland's glaciers have begun to race towards the ocean, leading scientists to predict that the vast island's ice cap is approaching irreversible meltdown, The Independent on Sunday can reveal.


Research to be published in a few days' time shows how glaciers that have been stable for centuries have started to shrink dramatically as temperatures in the Arctic have soared with global warming. On top of this, record amounts of the ice cap's surface turned to water this summer.

The two developments — the most alarming manifestations of climate change to date — suggest that the ice cap is melting far more rapidly than scientists had thought, with immense consequences for civilisation and the planet. Its complete disappearance would raise the levels of the world's seas by 20 feet, spelling inundation for London and other coastal cities around the globe, along with much of low-lying countries such as Bangladesh.

Thermohaline circulation shutdown

More immediately, the vast amount of fresh water discharged into the ocean as the ice melts threatens to shut down the Gulf Stream, which protects Britain and the rest of northern Europe from a freezing climate like that of Labrador.

The revelations, which follow the announcement that the melting of sea ice in the Arctic also reached record levels this summer, come as the world's governments are about to embark on new negotiations about how to combat global warming.

This week they will meet in Montreal for the first formal talks on whether there should be a new international treaty on cutting the pollution that causes climate change after the Kyoto protocol expires in seven years' time. Writing in The Independent yesterday, Tony Blair called the meeting "crucial", adding that it "must start to shape an inclusive global solution". But little progress is expected, largely because of continued obstruction from President George Bush.

The new evidence from Greenland, to be published in the journal Geophysical Research Letters, shows a sudden decline in the giant Helheim glacier, a river of ice that grinds down from the inland ice cap to the sea through a narrow rift in the mountain range on the island's east coast.

Professor Slawek Tulaczyk, of the Department of Earth Sciences at the University of California, Santa Cruz, told the IoS that the glacier had dropped 100 feet this summer.

Over the past four years, the research adds, the front of the glacier — which has remained in the same place since records began — has retreated four and a half miles. As it has retreated and thinned, the effects have spread inland "very fast indeed", says Professor Tulaczyk. As the centre of the Greenland ice cap is only 150 miles away, the researchers fear that it, too, will soon be affected.

Moving towards the sea at a rate of 113 feet a year; normal annual speed of a glacier is just one foot

The research echoes disturbing studies on the opposite side of Greenland: the giant Jakobshavn glacier — at four miles wide and 1,000 feet thick the biggest on the landmass — is now moving towards the sea at a rate of 113 feet a year; the normal annual speed of a glacier is just one foot.

The studies have found that water from melted ice on the surface is percolating down through holes on the glacier until it forms a layer between it and the rock below, slightly lifting it and moving it toward the sea as if on a conveyor belt. This one glacier alone is reckoned now to be responsible for 3 per cent of the annual rise of sea levels worldwide.

"We may be very close to the threshold where the Greenland ice cap will melt irreversibly," says Tavi Murray, professor of glaciology at the University of Wales. Professor Tulaczyk adds: "The observations that we are seeing now point in that direction."

Until now, scientists believed the ice cap would take 1,000 years to melt entirely, but Ian Howat, who is working with Professor Tulaczyk, says the new developments could "easily" cut this time "in half".

There is also a more immediate danger as the melting ice threatens to disrupt the Gulf Stream, responsible for Britain's mild climate. The current, which brings us as much heat in winter as we get from the sun, is driven by very salty water sinking off Greenland. This drives a deep current of cold ocean southwards, in turn forcing the warm water north.

Research at the Woods Hole Oceanographic Institute in Massachusetts has shown, that even before the glaciers started accelerating, the water in the North Atlantic was getting fresher in what it describes as "the largest and most dramatic oceanic change ever measured in the era of modern instruments".

Even before these discoveries, scientists had shortened to evens the odds on the Gulf Stream failing this century. When it failed before, 12,700 years ago, Britain was covered in permafrost for 1,300 years.