Last summer, for the first time in recorded history, boats could circumnavigate the North Pole. To the oblivious observer, this might seem like a good thing. Perhaps some green entrepreneur will build resorts on Finland's Svalbard Islands. However, as we know, there's a dark side...

The year 2009 may be the tipping point in human history when society responds to or ignores global warming. The UN climate meeting scheduled for Copenhagen in December may be humanity's last chance to avoid total chaos. It is too late to avoid some climate chaos.

For historical comparison, we might ask: When did someone on Easter Island first wonder if cutting down all the trees to roll stone statues around was really a good idea? A generation before they annihilated themselves?

Scientists on fire

Global climate news during the last year revealed an order-of-magnitude change in the effect of human greenhouse gas emissions. The news is the scale of the impact we are having.

Climate scientists are so concerned by emerging data that they doubt the reporting process can keep pace with actual impacts, and they scheduled an emergency summit in Copenhagen this month to communicate the climate urgency to world governments.

Alarm bells sounded last summer at Exeter University in the UK , when climatologist Kevin Anderson presented evidence to a climate conference that the Kyoto exercise has had zero net effect, and greenhouse gas emissions have increased beyond the bleakest earlier scenarios. For example, the 2007 Intergovernmental Panel on Climate Change (IPCC) report projected that Arctic summer sea-ice would 'disappear almost completely towards the end of the 21st century'. Now, data suggest the ice will be gone before 2015, a century ahead of previous estimates.

In 1992, when delegates first drafted the Kyoto outline, net global CO2 emissions were increasing by 0.9 per cent per year. Today, net emissions are increasing over three-times faster. The CO2 upsurge is driven by fossil fuel burning in Europe and North America, China's coal-powered boom, and industrial growth in the developing world, exacerbated by disappearing forests. Anderson and other scientists concluded that limiting the warming to the previous goal of 2°C is 'a lost cause'.

Former IPCC head, Bob Watson, warned that the world should prepare for a 4°C rise, at least, which will cause drought, food shortages, sea rise and more forest loss, decimating species and displacing millions of people. 'We're at the very top end of the worst case scenario,' he explains.

Nicholas Stern's 2006 report to the UK government, dismissed by denialists, now appears too conservative. Sterns says, 'I badly underestimated … the damages and risks of climate change.' Glacial melt in the Himalayas and Andes has reduced river flow and drinking water for billions of people. Agriculture is suffering from low water in China, Peru, East Africa and the American southwest. US Energy Secretary, physicist Steven Chu, told a US audience in February, 'We are on a path that scares me.'

At Stanford University, ecologist Christopher Field concludes, 'We are looking now at a future climate that's beyond anything we've considered seriously in climate model simulations.'

Katherine Richardson, from Copenhagen University, host of the emergency climate summit earlier this month, saids, 'This is not a regular scientific conference. This is a deliberate attempt to influence policy.' The scientists would be presenting 'disturbing' new data about the pace of global warming.

Later, in December, nations will meet in Copenhagen to replace the beleaguered and ineffective Kyoto agreement. This meeting may be humanity's last chance to forestall runaway global warming and avoid turning planet Earth into Easter Island writ large.

Runaway

Jim Hansen, of the US National Aeronautics and Space Administration (NASA), warns that dithering, denial, and censorship of scientific data, have brought humanity to the tipping point, after which natural climate feedback leads to runaway warming and sea level rise that we cannot stop. The feedback mechanisms are now well documented by science:

Albedo is the reflective power of any surface: Ice and snow reflect 35-85 per cent of sunlight that strikes it. The darker land or water left after the ice melts absorbs more heat. Water reflects only about 6 per cent of the sunlight, absorbing the rest as heat, which warms the air, melting more ice.

Methane: The so-called permafrost - across northern Canada, Alaska, Siberia, and Finland - is melting, releasing methane gas, 25 times more potent than CO2 at trapping heat in the atmosphere. The International Siberian Shelf Study, recorded 'methane chimneys' bubbling from the sea and air-borne concentrations 100-times background levels. University of Alaska scientist Katey Walter ignites Arctic methane seeps on the tundra, throwing flames seven metres into the air. Permafrost is now melting five metres below the surface, representing over two trillion metric tons of carbon (methane is CH4). This methane in the atmosphere will heat the planet, melt more ice and permafrost, and release more methane.

Forest destruction: Deforestation is responsible for about 20 per cent of greenhouse gas additions to the atmosphere. Less than half the world's peak forests remain, and we loose about 13 million hectares of forest every year. On top of this, rising temperatures and migrating insects are killing boreal forests, so the forests sequester less carbon, resulting in more heat and more dying forests.

Acidic seas: The seas absorb excess carbon, but this creates carbonic acid, which kills coral reefs and shellfish. Warmer oceans absorb less oxygen, creating dead zones and disrupting food chains. Dying organisms release carbon, so the seas absorb less CO2 than climate models had predicted.

Fires: The fires in Australia and elsewhere, intensified by warming temperatures, release both heat and carbon that causes more warming, risking more fires.

Melt holes: As polar ice melts, rivers run across the ice sheets, find cracks and create holes in the ice. The open holes expose deep ice to warmer air and water, melting the ice faster than IPCC models had predicted.

If, or when, these feedback loops reach a threshold (if they haven't already), nothing we do can stop the runaway warming. In Western Canada, where I live, shrinking snow packs reduce the annual river flow. At the Cowichan River on Vancouver Island, salmon could not make it upstream this year due to the low flow. Desperate citizens drove salmon upstream in trucks, burning more fuel, releasing more carbon. This might appear as a small contribution to the problem, but it is typical of the conundrum humanity faces. We're burning fossil fuel to 'solve' problems caused by burning too much fossil fuel.

A Thousand Atlantises

Susan Solomon, in a paper published by the US National Oceanic and Atmospheric Administration (NOAA), explains that environmental disruption will persist even if emissions are now brought under control. 'We're used to thinking about pollution problems as things that we can fix. Smog, we just cut back and everything will be better later … People have imagined that if we stopped emitting carbon dioxide that the climate would go back to normal in 100 years or 200 years. What we're showing here is ... an irreversible change that will last for more than a thousand years.'

Since warming is more severe towards the poles, the melting of the Greenland and West Antarctic ice sheets is accelerating. Katherine Richardson believes the 2007 IPCC report was 'wishy-washy' on addressing sea level rise.

A total planetary melt of polar and glacial ice would yield a 60 to 70 metre sea rise, which would ravage human society, doom species, and leave behind a thousand 'Atlantises' to replace the dead coral reefs as sites for marine life to start over. That scenario would force our progeny to restart humam society, growing food at higher elevations, in higher temperatures, on degraded land.

The world climate meeting in Copenhagen in December may be our last chance to avoid this scenario, and find some soft landing. Even so, scientists, who once talked about sea level rise in centimetres, are now predicting a 4 to 7 metre sea rise this century, in the lifetimes of our children and grandchildren. Even this scenario - a 7-metre sea rise - will swamp Shanghai, Bangkok, Miami, Dacca, Trieste, Venice, Mombassa, Lincolnshire, Brugge, Rotterdam, Amsterdam, Bremen, Gdansk and thousands of other coastal towns.

Meanwhile, well paid 'skeptics' exploit the natural uncertainty of science to keep climate change denial alive. A decade ago, the spin-meisters denied global warming at all; later, they blamed sunspots. Now that we know the recent warming is caused by human carbon emissions and forest destruction, we hear the deniers claiming that maybe global warming is 'beneficial' in some regions.

The Public Interest Research Centre (PIRC) report, which updated polar melting data, suggests that sabotage and procrastination by governments leave humanity with only one option: a crash energy diet, far beyond anything yet contemplated. If our actions do not operate at the same scale of the climate changes, they will prove irrelevant. We need at least an immediate 60 per cent cut in fossil fuel emissions before atmospheric CO2 levels will stop rising. We have never yet had any decrease in human history.

If we could achieve that, then the thermal momentum of the oceans will continue to warm the atmosphere for decades. The CO2 will endure for a millennium or more, and it may take many millennia thereafter for the world's climate to resemble the climate in which humans evolved, featuring minor warm and cool episodes.

Copenhagen 2009 must prove more effective than two decades of Kyoto handshakes. If we fail, then we prove ourselves no smarter than bacteria in a petri dish, the reindeer on St. Matthew Island, or the humans on Easter Island. If we fail, then we leave the Earth as those stone-statue makers left their island paradise, with monuments to our ignorance gazing out over a rising sea.

Rex Weyler