Monday, February 2, 2009

Melting Glaciers and Foot Shortages:
Growing Concern Over Alarming Statistics

--science + technology + innovation--

Glaciers around the globe are continuing to melt at high rates, according to data from the World Glacier Monitoring Service (WGMS) at the University of Zurich, Switzerland.

Tentative figures for the year 2007 indicate a further loss of average ice thickness from more than 80 glaciers of roughly 0.67 meter water equivalent (mwe). Some glaciers in the European Alps lost up to 2.5 wme.

Prof. Dr. Wilfried Haeberli, Director of the Service said: "The latest figures are part of what appears to be an accelerating trend with no apparent end in sight."

Data from close to 30 reference glaciers in nine mountain ranges indicate that between the years 2004-2005 and 2005-2006 the average rate of melting and thinning more than doubled. Glaciers with available long-term observation series around the world (30 glaciers in 9 mountain ranges) show a thickness reduction of 1.3 and 0.7 meters water equivalent (mwe) during the hydrological years 2006 and 2007, respectively.

The new data continues the global trend in accelerated ice loss over the past few decades and brings the cumulative average thickness loss of the reference glaciers since 1980 at almost 11.3 mwe.

Some of the most dramatic shrinking has taken place in Europe with Norway's Breidalblikkbrea glacier thinning by close to 3.1 metres (2.9 metre water equivalent) during 2006 compared with a thinning of 0.3 metres (0.28 metres water equivalent) in the year 2005. Other dramatic shrinking has been registered at Austria's Grosser Goldbergkees glacier, 1.2 metres in 2006 versus 0.3 in 2005; France's Ossoue glacier, nearly 3 metres versus around 2.7 metres in 2005; Italy's Malavalle glacier 1.4 metres versus around 0.9 metres in 2005; Spain's Maladeta glacier, nearly 2 metres versus 1.6 metres in 2005; Sweden's Storglaciaeren glacier, 1.8 metres versus close to 0.080 metres in 2005 and Switzerland's Findelen glacier, 1.3 metres versus 0.22 metres in 2005.

(European Alp's (still) largest glacier, the Aletsch glacier in 1900 and 2005)

Not all of the close to 100 glaciers monitored posted losses with some thickening during the same period including Chile's Echaurren Norte glacier while others, such as Bolivia's Chacaltaya glacier; Canada's Place glacier; India's Hamtah glacier and the Daniels and Yawning glaciers in the Untied States shrank less in 2006 than they did in 2005. However, for the close to 30 reference glaciers only one (Echaurren Norte in Chile) thickened over the same period.

(Riggs Glacier in Muir Inlet at Alaska's Glacier Bay National Park)

What many do not realize is the intricate connection between crops and glaciers. Glaciers are a vital part of the planet's system for collecting, storing and delivering the fresh water that billions of people depend on for washing, drinking, agriculture and power. Now that glaciers are disappearing and retreating, glacial lakes will burst, debris and ice will fall in avalanches, rivers will flood and then dry up, and sea levels will rise even further, say climate experts. Entire communities will be deprived of essential water, crops will be ruined and power stations which rely on river flows paralysed. One specific example of how glaciers can impact food crops is in India and China where irrigation water is vital for the grain crops. As Global warming melts the glaciers that feed Asia's biggest rivers.

The Ganges, Yellow and Yangtze Rivers in India and China are fed by rains during the monsoon season, but during the dry season they depend heavily on meltwater from glaciers in the Himalayas. The Gangotri Glacier in the Himalayas alone supplies 70% of the flow of the Ganges in the dry season. The dry season is precisely when water is needed most to irrigate the rice and wheat crops on which hundreds of millions of people depend for their staple calories. But the Intergovernmental Panel on Climate Change reported last year that many Himalayan glaciers could disappear by 2035.

The warning echoes another issued earlier this month by a former agriculture minister of Pakistan, Amir Mohammad, who warned that 60% of Pakistan's people depend on grain irrigated by the Indus river, which is also dependent on meltwater from Himalayan glaciers. "Melting of glaciers has already started affecting the water flow into Indus river system," he told local newspapers.

Experts are calling on political leaders to step up attempts to cut greenhouse gas emissions to slow and eventually stop global warming. Before then, however, they say governments need to do much more to encourage water efficiency, change to less water-thirsty crops and build flood protection and storage where possible. 'It's not a reason to sit back and say "it's all too late",' insists Steiner.

(Source: Science Daily,Guardian,ABC)

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