The land of melting snows

Back in the 13th century,explorer Marco Polo reported to incredulous Europeans that Chinese peasants burned a 'black rock'for heat.Today,more incredulous news:burning these black rock is destroying the planet.Lumps of coal burned in households in China result in a tremendous output of CO(not even taking industrial use of coal into account). That's China. On the other side of the Himalaya, a billion Indians are doing the same.And the emissions,known as black soot,are raining down on Himalayan peaks sited between the two heavily populated nations.

According to scientific studies,black soot deposition at some himalayan glaciers increased 30% between 1990 and 2003.Shimmering white glaciers in theory reflect the sun's heat,while 'dirty' glaciers (caused by black soot depositions) will do the exact pooosite:they will start absorbing the sun's rays thereby accelerating glacial meltdown.Most soot in the region comes from diesel engines,coal-fired power plants and outdoor cooking stoves.Multiply the cooking stoves by several billion to get an idea of how much black soot may be floaing around in the air.

This is not good news for Himalayan glaciers,which are melting rapidly due to climate-change factors.Tibet is the icebox of south Asia,with its myriad glaciers acting as major water-keeper for the entire region.With some 37,000 glaciers in Chinese-controlled Tibet alone,Lonnie Thompson,glaciologist at Ohio State University,calls the himalayan region 'Asia's freshwater bank account'.It's an icebox where massive build-up of new snows and ice (deposits) has traditionally offset its annual run-offf in rivers (withdrawals).But now the region is facing bankruptcy,because rapid withdrawals are depleting the account. Of the 680 glaciers currently monitored by Chinese scientists,95% are shedding more ice than they are adding,particuarly at the southern and eastern edges of the plateau.The glaciers are not simply retreating,they are losing mass from the surface down,says Thompson.

the first threat from glacial meltdown is GLOFs (Glacial Lake Outburst Floods).A GLOF is a large lake that is temporarily dammed by a glacier.if the dam bursts,entire villages can be washed away in a deluge of mud and water.This has happened in both Tibet and nepal.GLOFs pose serious threats in neighbouring Bhutan.Accelerated glacial meltdown in the Himalaya would lead initially to flooding from glacier-fed rivers. And much further down the road,it could lead to no water .If the glaciers vanish,the rivers would be reduced to a trickle.Monsoon rainwater alone is not enough to keep Himalayan rivers running at sufficient volume.

That's the snowline.Even more alarming is what is melting under the ground,in the ice below.The Tibetan plateau sits on the largest deposits of permafrost outside of the Arctic and Antarctic regions.Permafrost is found at various sub-surface depths across the entire Tibetan plateau.Due to climate-change factors,the permarost,frozen for millions of years,is gradually beginning to thaw.In the process of thawing,permafrost could release large amounts of carbon and methane,locked in ice crystals.In permafrost regions,methane hydrate is found trapped in layers between 150 and 2,000m deep.As a greenhouse gas,methane is thought to be over 20 times more potent than carbon dioxide in its ability to trap heat in the atmosphere.It is not known what effect the release of large amounts of methane into the atmosphere would have.