The scale of the problem can be realised when you factor in that huge populations dependent on glacier-fed rivers in Asia - 360 million on the Ganges in India and 388 million on the Yangtze in China alone - will not be able to feed themselves, with devastating effect on already rising global food prices. The problem is the most acute in Asia, where glaciers are an important source for nine major rivers which run through land occupied by 2.4 billion people. In Pakistan, for example, 80 per cent of agricultural land is irrigated by the Indus, which the WWF last year highlighted as one of the world's 10 big at-risk rivers because retreating glaciers provide 70-80 per cent of its flow.
According to a report by the world Glacier monitoring service, from 1850 to 1970, net losses averaged about 30cm a year; between 1970 to 2000 they rose to 60-90cm a year; and since 2000 the average has been more than one metre a year. Last year the total net loss was the biggest ever, 1.3m, and only one glacier became larger. Worldwide, the vast majority of the planet's 160,000 glaciers are receding at least at this rate or more! According to a UNEP report two-thirds of China's glaciers would disappear by 2050, and 'almost all would be gone by 2100'.
In North America, 99-plus per cent of Alaskan glaciers are either retreating or stagnating. In the European Alps, a report last year by UNEP said glaciers declined, from a peak in the 1850s, by 35 per cent by 1970 and by 50 per cent by 2000, and lost 5-10 per cent in the mega-hot year of 2003 alone. UNEP has also reported declines in the last 50-150 years of 1.3 per cent in the Arctic islands to 50 per cent in the North Caucasus in Russia, 25-50 per cent in central Asia, a 2km retreat of the massive Gangotri glacier which feeds the Ganges, 49 to 61 per cent in New Zealand, and 80 per cent in the high mountains of southern Africa. There is also 'considerable' shrinking of medium and small glaciers in central Chile and Argentina accompanied by 'drastic retreat' of glaciers in Patagonia to the south.
On a global level, scientists warn that melting glaciers are contributing more than ever to rising sea levels: expansion of warmer water is estimated to cause two-thirds of the problem, but melting glaciers and icecaps are the second biggest contributor. A recent paper published by Science calculated acceleration of glacier melt could add 0.1-0.25m to sea-level rise by 2100.
At a policy level, leaders around the world are still debating the means to address problems such as greenhouse emissions and carbon footprints. Outside in the wilderness, the last signs of earth's heritage, its glaciers are melting away more rapidly than we care to think about.
(reproduced from http://www.guardian.co.uk/environment/2008/mar/16/glaciers.climatechange)
According to a report by the world Glacier monitoring service, from 1850 to 1970, net losses averaged about 30cm a year; between 1970 to 2000 they rose to 60-90cm a year; and since 2000 the average has been more than one metre a year. Last year the total net loss was the biggest ever, 1.3m, and only one glacier became larger. Worldwide, the vast majority of the planet's 160,000 glaciers are receding at least at this rate or more! According to a UNEP report two-thirds of China's glaciers would disappear by 2050, and 'almost all would be gone by 2100'.
In North America, 99-plus per cent of Alaskan glaciers are either retreating or stagnating. In the European Alps, a report last year by UNEP said glaciers declined, from a peak in the 1850s, by 35 per cent by 1970 and by 50 per cent by 2000, and lost 5-10 per cent in the mega-hot year of 2003 alone. UNEP has also reported declines in the last 50-150 years of 1.3 per cent in the Arctic islands to 50 per cent in the North Caucasus in Russia, 25-50 per cent in central Asia, a 2km retreat of the massive Gangotri glacier which feeds the Ganges, 49 to 61 per cent in New Zealand, and 80 per cent in the high mountains of southern Africa. There is also 'considerable' shrinking of medium and small glaciers in central Chile and Argentina accompanied by 'drastic retreat' of glaciers in Patagonia to the south.
On a global level, scientists warn that melting glaciers are contributing more than ever to rising sea levels: expansion of warmer water is estimated to cause two-thirds of the problem, but melting glaciers and icecaps are the second biggest contributor. A recent paper published by Science calculated acceleration of glacier melt could add 0.1-0.25m to sea-level rise by 2100.
At a policy level, leaders around the world are still debating the means to address problems such as greenhouse emissions and carbon footprints. Outside in the wilderness, the last signs of earth's heritage, its glaciers are melting away more rapidly than we care to think about.
(reproduced from http://www.guardian.co.uk/environment/2008/mar/16/glaciers.climatechange)
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