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Xnn
#39
Dec7-09, 08:54 AM
P: 555
It's not good that they are putting stuff in the Impact section
which can not be found in the Science bases section.

Anyhow, here are the complete paragraphs.

Himalayan glaciers cover about three million hectares or 17%
of the mountain area as compared to 2.2% in the Swiss Alps.
They form the largest body of ice outside the polar caps and are
the source of water for the innumerable rivers that flow across
the Indo-Gangetic plains. Himalayan glacial snowfields store
about 12,000 km3 of freshwater. About 15,000 Himalayan
glaciers form a unique reservoir which supports perennial rivers
such as the Indus, Ganga and Brahmaputra which, in turn, are
the lifeline of millions of people in South Asian countries
(Pakistan, Nepal, Bhutan, India and Bangladesh). The Gangetic
basin alone is home to 500 million people, about 10% of the
total human population in the region.

Glaciers in the Himalaya are receding faster than in any other
part of the world (see Table 10.9) and, if the present rate
continues, the likelihood of them disappearing by the year 2035
and perhaps sooner is very high if the Earth keeps warming at
the current rate. Its total area will likely shrink from the present
500,000 to 100,000 km2 by the year 2035 (WWF, 2005).

The receding and thinning of Himalayan glaciers can be
attributed primarily to the global warming due to increase in
anthropogenic emission of greenhouse gases. The relatively high
population density near these glaciers and consequent
deforestation and land-use changes have also adversely affected
these glaciers. The 30.2 km long Gangotri glacier has been
receding alarmingly in recent years (Figure 10.6). Between 1842
and 1935, the glacier was receding at an average of 7.3 m every
year; the average rate of recession between 1985 and 2001 is
about 23 m per year (Hasnain, 2002). The current trends of
glacial melts suggest that the Ganga, Indus, Brahmaputra and
other rivers that criss-cross the northern Indian plain could likely
become seasonal rivers in the near future as a consequence of
climate change and could likely affect the economies in the
region. Some other glaciers in Asia such as glaciers shorter
than 4 km length in the Tibetan Plateau are projected to
disappear and the glaciated areas located in the headwaters of
the Changjiang River will likely decrease in area by more than
60% (Shen et al., 2002).
Table 10.9 lists 8 differant glaciers; how much they have receeded
and the average rate of recession over various time periods.
The rates vary between 5 to 135 m/year.

Anyhow, it's just surprising that the Indians themselves have not
made the effort to perform a comprehensive study. As glaciers
melt back at an accelerated rate, the meltoff will cause rivers
to flow at a greater rate during the melt season.
So, maybe they are all content with the enhanced river flow.

Eventually there will come a turning point when the flow will diminish.
However, specific projections need to be based on extensive and
comprehensive data and not just a hand full of points.