Michael McCarthy: Don't be fooled by this winter's powder. The Alpine snow line is already in retreat

Did you ski in the Alps last winter? Or do you have friends who did? All they could talk about, remember, was the snow, how terrific it was, the fantastic dry powder, tons of the stuff, the best snow for years.

Let's hope that wasn't the end of it. For last winter was an aberration, one of the coldest in Europe for a very long time – on 2 February there was a fall of eight inches of snow in London, for God's sake, an unheard-of occurrence these days – and the resultant heavy snowfalls in Alpine ski resorts blanketed over, as it were, people's perceptions of what has been steadily happening to western Europe's major mountain chain.

In truth, the Alpine snowfall trend is getting increasingly poorer, and the Alpine glaciers are very obviously melting rapidly, as global warming kicks in. In some of the glaciers, areas of permafrost that have been frozen for many thousands of years are now melting in the summer. I know a man who grew up in Geneva who used to enjoy snow at home every Christmas; he hasn't seen it for decades.

The Alps are like the Arctic, and the Antarctic, and Greenland, and the Himalayas: places of extreme conditions where climate change is already visible. This has immediate implications for the Alpine economy. In 2003, a report on the future of winter sports from the United Nations Environment Programme painted a dire picture of the not-too-distant future in ski resorts in France, Switzerland, Austria, Italy and Germany.

Over the next 30 to 50 years the snow line is expected to rise in many regions by anything from 500 to 1,000 ft. This means many of the lower-level ski stations will cease to be viable.