Lasse Bjerge lives in a remote, sub-Arctic valley that is flanked by barren mountains, 20 miles by boat from the nearest town and perishing cold even on a bright September day. There, for the past two years, he has cultivated one of the world’s most improbable market gardens.

As a bitter wind whistles past his red wooden cottage, Greenland’s first commercial vegetable farmer proudly lifts the synthetic sheeting protecting his crops to reveal rows of cabbages, cauliflowers and – appropriately – iceberg lettuces. This summer he even produced a few strawberries.

It is not easy, admits Mr Bjerge, 50, who began this experiment to supplement his sheep farmer’s paltry income. He was late buying his seedlings last spring because the fjord was choked with ice. There were frosts and freezing nights as late as June. His broccoli, in particular, has struggled to survive the harsh climate.

Now, thanks to Mr Bjerge and two other pioneering farmers, Greenlanders can buy fresh green produce for the first time – not the tired, limp stuff flown in at exorbitant cost from Denmark. Mr Bjerge breaks up a compact cauliflower head. “Taste it,” he says. It is crisp, sweet and full of flavour, because it has taken weeks to ripen in the long, cool days of a far northern summer.

Until recently commercial vegetable production would have been almost impossible in this land of ice and rock – but global warming is greening Greenland.

“We live on the margins of where things grow, and an extra one or two degrees can make all the difference,” says Kenneth Hoegh, Greenland’s chief agricultural adviser. Within ten years Greenland could be self-sufficient in vegetables, according to Jonstein Gard, of the Upernaviarsuk agricultural research station – whose own vegetable garden has become something of a tourist attraction. “Commercial farming is becoming more and more possible.” Greenland is on the front line of climate change. For the 57,000 inhabitants of the world’s biggest island, global warming is a present-day reality that is creating new opportunities, destroying old lifestyles and transforming landscapes – and it could well secure Greenland’s long-sought independence from Denmark.

There is probably no other place on Earth where the impact is so marked. “In London you don’t feel climate change. Here everybody is affected,” says Kim Hoegh, head of Arctic Prime, a fish processing company. “We see it with our own eyes, and feel it in our daily lives. Something is happening that’s unnatural.”

It is not all good news. Inhabitants of the tiny communities scattered around Greenland’s jagged southern rim, many of which are accessible only by boat or helicopter, say that there are many more sudden, unpredictable storms that make travel perilous.

Mr Hoegh says that the fishing fleet goes out less often in winter than it used to. In one village, a cluster of brightly painted houses on a coastal island called Nanortalik, there have been at least three fatal boating accidents in two years.

Greenlanders point to the mountains and lament the disappearance of the snowcaps and tongues of glacial ice that used to flow down between the peaks. The Times visited a remote fjord, Sermilik Brae, where the ice cap that covers most of Greenland descends right to the water. The giant body of ice had retreated three miles up the fjord in the past 15 years. We could tell exactly how much it had shrunk because, as we nosed up the fjord between hunks of floating ice, our boat’s GPS system showed us reaching the ice cap three miles prematurely. It was programmed in the 1990s.

For Greenland’s hunters, climate change is a disaster. In the north the Arctic ocean no longer freezes solid all through the winter, preventing the Inuits hunting seals on their dog sleds. In the south, men like Jakob Petersen, 61, rely on the huge slabs of ice that drift down from the north each spring to bring seals and calm the seas for hunting – but that ice no longer comes in big enough pieces, and it disappears earlier.

Mr Petersen, selling the blubber and meat of one lone seal and two small whales by the harbour in Nanortalik, said: “It’s getting worse very quickly. I used to catch about 800 seals a year. Now I only get about 200. I can no longer earn a living from hunting.” In his youth every man in the village was a hunter, he said. Now there were only half a dozen left.

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