Trouble at Third Pole
The Himalayas, home to the largest
glaciers outside the two poles, is feeling the heat of climate change
The Himalayas, which is considered invincible and unconquerable, have
been noticeably impacted by climate change. The greater Himalayan
region, called “ the roof of the world”, contains the most extensive and
rugged high alti tude areas on earth.
These are the largest areas covered by glaciers and permafrost
outside the Polar regions and the area is now being called the Third
Pole.
The melt waters of this area drain through 10 of the largest rivers
in Asia and the basins are home to more than 1.3 billion people.
These water resources play an important role in global atmospheric
circulation, biodiversity, rain-fed and irrigated agriculture and
hydropower. With climate change happening, the most widely reported
impact is the rapid reduction in glaciers which cause massive
repercussions to livelihoods downstream.
Khumbu Glacier |
Adverse impact
China and India are the two leading producers of rice in the world
with most of the harvest coming from the Ganges basin, and the Yangtze
and Yellow River basins. But with the spectre of climate change, the
Stern report (2006) has said, “China’s human development could face a
major U-turn by mid century unless urgent measures are taken to ‘climate
proof’ development results.”
Himalayan Glaciers are receding faster today than the world average.
According to scientists in China, in the last half of the 20th century,
82 per cent of the glaciers in Western China have retreated.
On the Tibetan Plateau, the glacial area has decreased by 4.5 per
cent over the last 20 years and over seven per cent over the last 40
years, indicating an increased retreat rate.
The scientists say the glacier retreat in the Himalayas results from
precipitation decrease in combination with temperature increase. Glacier
shrinkage will speed up if climatic warming and drying continues.
In fact, the IPCC Fourth Assessment Report in 2007 states that in the
coming decades, many glaciers in the region will retreat, while smaller
ones will disappear altogether. So it is reasonable to conclude that
with a two per cent increase by 2050, 35 per cent of the present
glaciers will disappear and run off will increase, peaking between 2030
and 2050.
Disaster ahead
In Asia, climate change-induced glacial melt could seriously affect
half a billion people in the Himalayan region, and a quarter of a
billion people in China, people who depend on glacial melt for their
water supply (Stern 2007).
Perennial rivers like the Indus, Ganga and Brahmaputra are all fed by
the unique reservoir formed by the 16,000 Himalayan glaciers. The
current trends in glacial melt suggest that the low flow will become
substantially reduced as a consequence of climate change (IPCC 2007a)
The effect of this on food production will be catastrophic.
The situation, say scientists, may appear to be normal for several
decades; however when the shortage happens, it will happen abruptly with
water systems going from plenty to scarce in a few decades. Finally, it
is the poorest who will get hit. The International Centre for Integrated
Mountain Development (ICIMOD), Kathmandu, Nepal, has conducted ongoing
studies on glacial lakes which have formed in the area left at the foot
of the retreating glaciers. An inventory conducted by ICIMOD in 2009
identified 8,790 glacial lakes in parts of the Hindu Khush Himalayas.
“Around 204 of these lakes are considered to be potentially dangerous
in that they are liable to burst their banks leading to what is known as
a glacial lake outburst flood (GLOF). There have been approximately 35
GLOF disasters in Bhutan, China and Nepal in the 20th century,” says
Syed Iqbal Husnain of TERI, who is India’s foremost glaciologist, during
his talks in Kathmandu in September 2009.
As he said, “Climate change has become a major issue in the Hindu
Khush – Himalayan region as the mountain regions are particularly
vulnerable.”
In some ways global challenges like climate change and poverty can be
seen as great dividers — exposing the degrees of separation between
people who can afford to cope and people who cannot.
Hopefully COP 15 can look towards the world’s countries working
together to reduce emissions irrespective of being developed or not.
The Hindu |