If the Greenland ice field were to melt, it would raise sea levels about 7 meters (23 feet).

New evidence indicates that the melting of Greenland has reach the point of no return.

This will devastate most of the coastal cities across the world:

Annual snowfall can no longer replenish the melted ice that flows into the ocean from Greenland’s glaciers. That is the conclusion of a new analysis of almost 40 years’ satellite data by researchers at Ohio State University. The ice loss, they think, is now so great that it has triggered an irreversible feedback loop: the sheet will keep melting, even if all climate-warming emissions are miraculously curtailed. This is bad news for coastal cities, given that Greenland boasts the largest ice sheet on the planet after Antarctica. Since 2000 its melting ice has contributed about a millimetre a year to rising sea levels. The loss of the entire ice sheet would raise them by more than seven metres, enough to reconfigure the majority of the world’s coastlines.

In the 1980s and 1990s, Greenland’s ice maintained a rough equilibrium. Each year the sheet lost some 400bn tonnes of ice in the summer—both by ice and snow melting on the surface, and the “discharge” of ice by glaciers losing chunks as they push out into the sea. This was replenished by a similar amount of fresh snow in the winter. But after 2000 the ice sheet began losing mass permanently. The amount that has disappeared is so huge that it has caused a noticeable change in the gravitational field over the island. It has also caused the glaciers to retreat by about 3km since 1985, exposing more of them to warmer ocean water. This has increased the rate of melting to the point where, even if the climate stopped getting hotter, more ice would be discharged each year than could be replaced, the scientists reckon. “The ice sheet is now in this new dynamic state, where even if we went back to a climate that was more like what we had 20 or 30 years ago, we would still be pretty quickly losing mass,” explains Ian Howar, one of the study’s authors.

Over the past three decades, the Arctic has warmed at least twice as fast as the rest of the world. This is because of a phenomenon known as Arctic amplification, in which higher concentrations of greenhouse gases produce larger increases in temperature at high latitudes. It also means that changes in the Arctic region are an important indicator of the progression and impacts of climate change. The decline of the Greenland ice sheet is a harbinger of things to come. “Greenland is going to be the canary in the coal mine,” says Mr Howar. “And the canary is pretty much dead at this point.”

Clearly people operating in their own enlightened self-interest, as the religion of the free-market mousketeers, is not working.

Permafrost in Canada is melting at a rate faster than the most alarmist models predicted:

Permafrost at outposts in the Canadian Arctic is thawing 70 years earlier than predicted, an expedition has discovered, in the latest sign that the global climate crisis is accelerating even faster than scientists had feared.

A team from the University of Alaska Fairbanks said they were astounded by how quickly a succession of unusually hot summers had destabilised the upper layers of giant subterranean ice blocks that had been frozen solid for millennia.

“What we saw was amazing,” Vladimir Romanovsky, a professor of geophysics at the university, told Reuters. “It’s an indication that the climate is now warmer than at any time in the last 5,000 or more years.“

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The paper was based on data Romanovsky and his colleagues had been analysing since their last expedition to the area in 2016. The team used a modified propeller plane to visit exceptionally remote sites, including an abandoned cold war-era radar base more than 300km from the nearest human settlement.

Diving through a lucky break in the clouds, Romanovsky and his colleagues said they were confronted with a landscape that was unrecognisable from the pristine Arctic terrain they had encountered during initial visits a decade or so earlier.

The vista had dissolved into an undulating sea of hummocks – waist-high depressions and ponds known as thermokarst. Vegetation, once sparse, had begun to flourish in the shelter provided from the constant wind.

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Even if current commitments to cut emissions under the 2015 Paris agreement are implemented, the world is still far from averting the risk that these kinds of feedback loops will trigger runaway warming, according to models used by the UN-backed Intergovernmental Panel on Climate Change.

 We are in for a world of hurt.