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Vast cracks appear in Arctic ice

By David Shukman

Environment correspondent, BBC News

Dramatic evidence of the break-up of the Arctic ice-cap has emerged from research during an expedition by the Canadian military. Scientists travelling with the troops found major new fractures during an assessment of the state of giant ice shelves in Canada's far north. The team found a network of cracks that stretched for more than 10 miles (16km) on Ward Hunt, the area's largest shelf. The fate of the vast ice blocks is seen as a key indicator of climate change.



One of the expedition's scientists, Derek Mueller of Trent University, Ontario, told me: "I was astonished to see these new cracks. "It means the ice shelf is disintegrating, the pieces are pinned together like a jigsaw but could float away," Dr Mueller explained.

According to another scientist on the expedition, Dr Luke Copland of the University of Ottawa, the new cracks fit into a pattern of change in the Arctic. "We're seeing very dramatic changes; from the retreat of the glaciers, to the melting of the sea ice. "We had 23% less (sea ice) last year than we've ever had, and what's happening to the ice shelves is part of that picture." When ice shelves break apart, they drift offshore into the ocean as "ice islands", transforming the very geography of the coastline.



Last year, I was part of a BBC team that joined Dr Mueller and Dr Copland as they carried out the first research on Ayles Ice Island, an iceberg the size of Manhattan. It has since split into two, each vast chunk of ice now 400 miles (640km) south of its original position. The rapid changes in the Arctic have reignited disputes over territory. The Canadian military's expedition was billed as a "sovereignty patrol", the lines of snowmobiles flying Canadian flags in a display of control.

After the record Arctic melting last year, all eyes are now on what happens to the sea ice this summer. Although its maximum extent last winter was slightly greater than the year before, it was still below the long-term average.

Scrat;873457 wrote: If that ice melting dilutes the northern atlantic too much we know that the Gulf Stream pump shuts down. That means northern europe could get very cold.


I know.



What worries me is the speed at which things seem to be changing. It suggests that replying on the hope that this was gonna play out according to the best case scenarios was a little foolish. What its gonna be like in 20 or even 10 years time is starting to become anyone's guess. Very alarming indeed.

Okay that does it! Declare global eminent domain and annex the area. Any resistance will be considered acts of terrorism. We should be able to get plenty of volunteers to guard the perimeter from all the environmental groups. We'll build a human wall all the way 'round by having them all join hands -- a group hug for the rainforest.

Accountable;873592 wrote: Okay that does it! Declare global eminent domain and annex the area. Any resistance will be considered acts of terrorism. We should be able to get plenty of volunteers to guard the perimeter from all the environmental groups. We'll build a human wall all the way 'round by having them all join hands -- a group hug for the rainforest.




Good luck debating political theory with the ocean. I think King Lear may have already tried it though.

Arctic sea ice melt 'even faster'

By Richard Black

Environment correspondent, BBC News website

Arctic sea ice is melting even faster than last year, despite a cold winter. Data from the US National Snow and Ice Data Center (NSIDC) shows that the year began with ice covering a larger area than at the beginning of 2007. But now it is down to levels seen last June, at the beginning of a summer that broke records for sea ice loss. Scientists on the project say that much of the ice is so thin that it melts easily, and the Arctic may be ice-free in summer within five to 10 years.



I think we're going to beat last year's record, though I'd love to be wrong Julienne Stroeve "We had a bit more ice in the winter, although we were still way below the long-term average," said Julienne Stroeve from NSIDC in Boulder, Colorado. "So we had a partial recovery; but the real issue is that most of the pack ice has become really thin, and if we have a regular summer now, it can just melt away," she told BBC News.

In March, Nasa reported that the area covered by sea ice was slightly larger than in 2007, but much of it consisted of thin floes that had formed during the previous winter. These are much less robust than thicker, less saline floes that have already survived for several years.

After a colder winter, ice has been melting even faster than last year

A few years ago, scientists were predicting ice-free Arctic summers by about 2080. Then computer models started projecting earlier dates, around 2030 to 2050. Then came the 2007 summer that saw Arctic sea ice shrink to the smallest extent ever recorded, down to 4.2 million sq km from 7.8 million sq km in 1980. By the end of last year, one research group was forecasting ice-free summers by 2013.

"I think we're going to beat last year's record melt, though I'd love to be wrong," said Dr Stroeve. "If we do, then I don't think 2013 is far off anymore. If what we think is going to happen does happen, then it'll be within a decade anyway." Rising tide Countries surrounding the Arctic are eyeing the economic opportunities that melting ice might bring. Canada and Russia are exploring sovereignty claims over tracts of Arctic seafloor, while just this week US President George Bush has urged more oil exploration in US waters - which could point the way to exploitation of reserves off the Alaskan coast.



Summer ice cover in the Arctic has declined sharply But from a climate point of view, the melt could bring global impacts accelerating the rate of warming and of sea level rise. "This is a positive feedback process," commented Dr Ian Willis, from the Scott Polar Research Institute in Cambridge. "Sea ice has a higher albedo (reflectivity) than ocean water; so as the ice melts, the water absorbs more of the Sun's energy and warms up more, and that in turn warms the atmosphere more - including the atmosphere over the Greenland ice sheet." Greenland is already losing ice to the oceans, contributing to the gradual rise in sea levels. The ice cap holds enough water to lift sea levels globally by about seven metres (22ft) if it all melted.

Natural climatic cycles such as the Arctic Oscillation play a role in year-to-year variations in ice cover. But Julienne Stroeve believes the sea ice is now so thin that there is little chance of the melting trend turning round. "If the ice were as thin as it was in the 1970s, last year's conditions would have brought a dip in cover, but nothing exceptional. "But now it's so thin that you would have to have an exceptional sequence of cold winters and cold summers in order for it to rebuild."

Richard.Black-INTERNET@bbc.co.uk

Scrat;892805 wrote: Brings a lot of uncertainty into the picture. We'll see in the next few years.


Appears that Spot might not have been too far off

Here we go, buckle up boys.



Exclusive: No ice at the North Pole

Polar scientists reveal dramatic new evidence of climate change

By Steve Connor, Science Editor

Friday, 27 June 2008



It seems unthinkable, but for the first time in human history, ice is on course to disappear entirely from the North Pole this year.

The disappearance of the Arctic sea ice, making it possible to reach the Pole sailing in a boat through open water, would be one of the most dramatic – and worrying – examples of the impact of global warming on the planet. Scientists say the ice at 90 degrees north may well have melted away by the summer.

"From the viewpoint of science, the North Pole is just another point on the globe, but symbolically it is hugely important. There is supposed to be ice at the North Pole, not open water," said Mark Serreze of the US National Snow and Ice Data Centre in Colorado.

If it happens, it raises the prospect of the Arctic nations being able to exploit the valuable oil and mineral deposits below these a bed which have until now been impossible to extract because of the thick sea ice above.

Seasoned polar scientists believe the chances of a totally icefreeNorth Pole this summer are greater than 50:50 because the normally thick ice formed over many years at the Pole has been blown away and replaced by hugeswathes of thinner ice formed over a single year.

This one-year ice is highly vulnerable to melting during thesummer months and satellite data coming in over recent weeksshows that the rate of melting is faster than last year, when therewas an all-time record loss of summer sea ice at the Arctic.

"The issue is that, for the first time that I am aware of, the NorthPole is covered with extensive first-year ice – ice that formed last autumn and winter. I'd say it's even-odds whether the North Pole melts out," said Dr Serreze.

Each summer the sea ice melts before reforming again during the long Arctic winter but the loss of sea ice last year was so extensive that much of the Arctic Ocean became open water, with the water-ice boundary coming just 700 miles away from the North Pole.

This meant that about 70 per cent of the sea ice present this spring was single-year ice formed over last winter. Scientists predict that at least 70 per cent of this single-year ice – and perhaps all of it – will melt completely this summer, Dr Serreze said.

"Indeed, for the Arctic as a whole, the melt season startedwith even more thin ice than in 2007, hence concerns that we may even beat last year's sea-ice minimum. We'll see what happens, a great deal depends on the weather patterns in July and August," he said.

Ron Lindsay, a polar scientist at the University of Washington in Seattle, agreed that much now depends onwhat happens to the Arctic weather in terms of wind patterns and hours of sunshine. "There's a good chance that it will all melt awayat the North Pole, it's certainly feasible, but it's not guaranteed," Dr Lindsay said.

Thepolar regions are experiencing the most dramatic increasein average temperatures due to global warming and scientists fear that as more sea iceis lost, the darker, open ocean will absorb more heat and raise local temperatures even further. Professor Peter Wadhams of Cambridge University, who was one of the first civilian scientists to sail underneath the Arctic sea ice in a Royal Navy submarine,said that the conditions are ripe for an unprecedented melting of the ice at the North Pole.

"Last year we saw huge areas of the ocean open up, which hasnever been experienced before. People are expecting this to continuethis year and it is likely to extend over the North Pole. It isquite likely that the North Pole will be exposed this summer – it's not happened before," ProfessorWadhamssaid.

There are other indications that the Arctic sea ice is showingsigns of breaking up. Scientists at the Nasa Goddard Space Flight Centre said that the North Water 'polynya' – an expanse of open water surrounded on all sides by ice – that normally forms near Alaska and Banks Island off the Canadian coast, is muchlarger than normal. Polynyas absorb heat from the sun and eat away at the edge of the sea ice.

Inuit natives living near Baffin Bay between Canada and Greenland are also reporting thatthe sea ice there is starting to break up much earlier than normal and that they have seen wide cracks appearing in the ice where it normally remains stable. Satellite measurements collected over nearly 30 years show a significant decline in the extent of the Arctic sea ice, which has become more rapid in recent years.

[URL="javascript:launchPopup('http://www.independent.co.uk/environmen ... gallery=no','', 394, 1036, true, true, true, false);"][/URL]



Why didn't we hear about this last year, when there was record melting?

Because the seasonal effect of thinning ice is cumulative, and these record melting of the last few years, has thinned the ice to the point where the increased melting this year has finally resulted in the North Pole being uncovered. This trend is going to increase every year now, until there is no more Ice in the arctic in summer, eventually we will also see the enourmous land-mass supported Ice sheets in Greenland and Antarctica starting to break down, (particularly Greenland) and once this happens massive sea level rises will become inevitable. A huge program of re-population away from coastal areas will have to be undertaken, somehow.

What you should realize is that the actual melting and changes we are witnessing are much worse than most climate science has predicted, as climate scientists are being quite conservative in their opinions, as there is so much open hostility to the idea that global warming is even real. ]

My own view is that its far, far worse than most people realize, and that we are going to have to deal with unprecedented climate destabilization within a decade or two. Whether thats even possible to deal with is now open to question, as it looks like we may be facing worst case scenarios, unfortunately, but its certainly going to happen whether you accept it or not.

One of the biggest problems at the moment is that people - good, intelligent people - really believe that most of this crisis is about scientists scrabbling for grant money and that it doesn't exist in the real world. The fact that most governments have taken it on board is discounted, because this is regarded as actual grounds for disbelief by the over-cynical. ie most of us.

Frankly, I look at the rage torn sky and wonder how anyone can think it isn't real. But that's just me.

Australia faces food crisis as rivers reach new low

By Kathy Marks in Sydney

Friday, 11 July 2008

The drought in Australia's main food bowl, the Murray-Darling Basin, has worsened, with record low inflows into the river system in June and an even gloomier situation predicted for the coming months.

Neil Plummer, acting head of the National Climate Centre, described rainfall during the southern hemisphere autumn as "an absolute shocker", and said: "I'm gasping for good news". Wendy Craik, chief executive of the Murray-Darling Basin Commission, said the river system's condition was "critical... tending towards flatlining". She added: "We have got it on life support."

The basin, which straddles four states and is the size of France and Germany combined, produces 41 per cent of Australia's fruit, vegetables and grain. Agricultural products worth more than £10bn are exported from the region annually to Asia and the Middle East.

But flows of water last month into the two mighty rivers that irrigate the basin were the lowest since records began 117 years ago, equating to only 16 per cent of the June average. During February to June, the levels were only marginally higher than last year, which was the driest autumn on record.

The dire assessment of the rivers' health came only a few days after government scientists warned that Australia – the world's driest populated continent – could expect the frequency of heatwaves to increase tenfold, from once every 22 years to every one or two years. They also predicted that droughts would occur twice as often and affect twice the usual area. The findings were described by the Agriculture Minister, Tony Burke, as reading "more like a disaster novel than a scientific report".

The state of the Murray-Darling is of great concern to two groups: farmers and environmentalists. The former depend on it to irrigate crops such as rice, grapes and horticulture. The latter point to scientific reports saying the river system's unique ecology could be irreversibly damaged by October without heavy rain.

Salvation seems unlikely. Dr Craik said yesterday that hopes of drought-breaking winter rains had faded, and low inflows were expected for the rest of the year. Temperatures are forecast to be above average for the next three months, which means rain is more likely to soak into the sun-baked earth or evaporate than flow into the rivers.

Mr Plummer said good rains early in the year had barely dented the drought, and long-term trends pointed to six to seven years of below average rain in each decade. Of recent months, he said: "Autumn can only be described as an absolute shocker in terms of climate conditions for the basin."

Scientists say the lower reaches of the Murray, where lakes and vast wetlands meet the sea, are almost "beyond recovery", with wetlands dried up, vegetation lost, some native fish species wiped out and others facing extinction. The lakes are becoming acidic, and wildlife habitats are under threat.

Dr Craik raised the pros-pect that communities dependent on the Murray's tributaries might have to have water trucked in. "Regrettably, the drought is getting worse," she said.

Australia's most punishing drought in a century has forced about 10,000 farming families off the land, and threatened the economic viability of some agricultural towns. Ross Garnaut, the government's chief climate change adviser, warned in a report last week that irrigated agricultural production in the Murray-Darling Basin would decline by 92 per cent by 2100.

The drought, which began six or seven years ago, and has been particularly crippling over the past 12 months and has wiped more than $20bn (£9.3m ) off the economy since 2002.

Even if rainfall returns to average levels, the basin area – the source of 70 per cent of Australia's irrigated agriculture – will continue to suffer because of higher temperatures. Meteorologists have established that for every one degree Celsius rise in temperature, inflows into the river system decrease by 15 per cent.

"The catchments are very dry," said Dr Craik. "And the outlook, unfortunately, for rain is drier than average. Put all that together, and you don't have a very encouraging scenario."

News from the oceans

A third of the world’s coral species are threatened with extinction, according to an international study that revealed rapid and alarming deterioration in the state of coral reefs over the past 10 years.

Many will have disappeared by the end of the century unless global warming, pollution and over-fishing are curbed, warned scientists in the most damning and definitive assessment on tropical corals yet delivered.

Coral reefs, the only living structures that can be seen from space, are often compared with tropical rainforests for the diversity and wealth of wildlife and plants that live in and around them. Their loss could also threaten the 25 per cent of marine species that need them for survival, as well as endangering the livelihoods of the estimated 200 million people who rely on them either for food or as a source of income.

An international team of scientists found that 231 of the 704 reef-building corals the study was able to assess were in such a poor state that they had fallen into the three most-threatened categories of species as defined by the International Union for the Conservation of Nature (IUCN). Its Red List of species has seven categories. As of yesterday, the 231 coral species on the Red List have been formally classified as either “vulnerable, “endangered or “critically endangered.

The 39 scientists from 14 countries also investigated the remaining 141 reef-building coral species but could not gather enough information on them to make an accurate assessment. But they believe many of these corals are also highly likely to be threatened with extinction.

What made the study even more urgent was scientists’ ability to calculate what state the corals were in before 1998, when a significant rise in sea-surface temperatures was linked with a worldwide outbreak of coral “bleaching, when corals as far apart as the Caribbean and the Indian Ocean lost their colour because of heat stress.

The scientists found that only 13 species of reef-building corals before 1998 would have fallen into the three most-endangered categories. This means there has been an almost 20-fold increase in the threat to corals in a decade.

They cited rising sea temperatures, caused by global warming, pollution from such human activities as sewage and agricultural run-off, and over-fishing as the biggest threats. But they warn that all of these may be eclipsed by the threat of rising ocean acidity caused by increases in atmospheric carbon dioxide, which could eventually dissolve the calcium carbonate skeletons of reef-building corals.

Kent Carpenter of the Old Dominion University in Norfolk, Virginia, who directed the global coral assessment for the IUCN, said the threat to the corals is probably unprecedented in modern times. “The results of this study are very disconcerting, Dr Carpenter said. “When corals die off, so do the other plants and animals that depend on coral reefs for food and shelter, and this can lead to the collapse of entire ecosystems. If you are interested in biodiversity I would say this is one of the most alarming findings in terms of marine life.

The threat of the extinction of corals could match the mass extinction that wiped out almost half of the corals 65 million years ago, along with the dinosaurs, in a geological event known as the Cretaceous-Tertiary boundary, he said. “We know that conditions existed on Earth that allowed huge numbers of extinctions. These extinctions that existed in geological times could be mimicked by what is happening on Earth today.

“The sort of changes that we as humans are bringing about could essentially be the same sort of catastrophic event that caused the Cretaceous-Tertiary mass extinctions. That took a while. This is probably faster.

The study is published in the journal Science and was released yesterday at the International Coral Reef Symposium in Fort Lauderdale, Florida. The scientists said corals are now rated second only to amphibians as the most threatened group of animals on Earth. “The proportion of corals threatened with extinction has increased dramatically in recent decades and exceeds most terrestrial groups, they added. Roger McManus, vice president of marine programmes at Conservation International, said that if sea-surface temperatures continue to rise, causing more frequent episodes of coral bleaching, it will be increasingly difficult for corals to survive further environmental insults.

“These results show that as a group, reef-building corals are more at risk of extinction than all terrestrial groups, apart from amphibians, and are the most vulnerable to the effects of climate change, Dr McManus added. “The loss of corals will have profound implications for millions of people who depend on coral reefs for their livelihoods.

Julia Marton-Lefevre, director general of the IUCN, said: “We either reduce CO2 emissions now or many corals will be lost forever. Improving water quality, global education and the adequate funding of local conservation practices are also essential to protect the foundation of beautiful and valuable coral reef ecosystems.