The fact that Europe’s glaciers are shrinking is no longer news to anyone who goes skiing. A little over a century ago a Gap based botanist noticed changes in the flora on the terminal moraines in the Alps and published a prescient article entitled: “Are these indications of a coming change in climate?”. In the 50s and 60s the French Alpine Club’s house Magazine “Montagne” also published a series of articles on the shrinking glaciers that ski mountaineers had noticed. Now a report presented today in Monaco by the PNUE (Programme des Nations Unies pour l’environnement) shows just how serious the shrinkage has been.
Glaciers in the European Alps have lost two thirds of their volume and it is a phenomena that is accelerating. Climatologists see glaciers are the canary in the climate change coal-mine. Although changes in volume lag behind average air temperatures and can be affected by increased snow fall at altitude they give a steady but sure indication of temperature changes. The PNUE study shows that Alpine glaciers lost 50% of their volume from 1850 to 1975 then a further 25% from 1975 to 2000. Between 2000 and 2005 they lost a further 10 to 15%. The study highlighted losss of bio diversity, an accelerating increase in sea level, acidification of the oceans and an increase the annual number of hurricanes.
Changes are even occurring on the high plateau of Qinghai in Tibet, with a glaciated area of 5.94 million hectares and some 5,590 cubic km of ice. The glaciers have decreased by 7% in the second half of the 20th century leading to an 5.5% increase in water flows in the north-west of China.
Glaciers have been in retreat since the end of the little ice age in Europe around 1850. Evidence suggests that during a warm period which ended in the 13th century the extent of glaciation was even less than today. It is possible that silver mining at the medieval Brand village above l’alpe d’Huez ended with the onset of harsher winters.