Everest glacier is melting due to global warming
Glacial ice is formed from highly compressed snow. In areas of the world where more snow falls each year than can melt or evaporate, the snow builds up and its structure gradually changes. After that, the compressed snow, known as firn is transformed to glacial ice.
One of the key facts about gaciers is that around 80 percent of the world’s fresh water is locked up inside glaciers, mostly around the poles (ice sheets on Antarctica and Greenland). When summer temperatures bring about the rapid melting of a glacier, the meltwaters that flow downhill release the stored fresh water, replenishing the overall water supply.
The glaciers in the Himalaya are not just sliding downhill, they also appear to be melting faster than they can be replenished. The ice is critical for Nepal because it feeds many of the rivers which are Nepal’s primary source of drinking and irrigation water. If these ice fields and glaciers disappear, Nepal and India will have to depend on the unreliable monsoon rains for water.
Glaciers are also affected by seasonal changes in climat, melting in hot summers or refreezing in cold winters. In fact, this determines whether a glacier is in the process of advancing (moving downhill) or retreating (melting). Glaciers have an impact on weather, too. The sharp contrast between the frigid air around the poles and the warmer air around the equator sets up a temperature differential that results in the giant jet streams of wind that circle the planet, and also relalates to storm development.
One of Mount Everest’s most-visited glaciers is continuously melting into a growing lake which now threats villagers and trekking tourists, scientists have warned few days ago.
A study of glacial melting in the high Himalaya found that the Imja glacier has melted from solid ice in the mid-1950s to a almost two and a half kilometers long lake today.
Scientists from Nepal’s International Centre for Integrated Mountain Development (ICIMOD) said the lake is growing by just under 50 meters per year. Such increasing growing rate poses a danger of bursting lake’s banks – a 31 meters high dam mostly of rocks and stones – and flooding nearby villages and trekking routes.
There are some scientists’ predictions that more than 7,500 people would be affected by the floods.
The study compared photographs taken from the 1956 Swiss Everest expedition, which showed no evidence of a lake on the glacier, to later pictures and revealed the creation of a large lake.
“Photographs taken in the 1950s demonstrate that, except for several small melt ponds, no lake existed at that time. By 1984 a lake of approximately 0.4 square kilometers had formed,” the report said.
A series of maps drawn from photographs “demonstrate the progressive evolution of 1956 melt ponds to a potentially threatening lake by 1984,” the authors added.
They urged the authorities in Nepal to install early warning systems to sound imminent flood alerts.
The three lakes in the study had all become tourist attractions, they said.
One of the authors, Pradeep Mool, a leading Himalayan glacier expert, said the study had been aimed at establishing which of the region’s “potentially dangerous” glacial lakes could burst in the future.
Global warming was the cause of the glacier’s rapid meltdown and transformation into a lake.
“Without the warming the ice will not melt. The rate of melt has increased because of exposure to atmospheric warming in the last few decades. It’s a very beautiful lake but it is one of the lakes in potential danger of an outburst [of water],” he said.
The research, including scientific photography and the use of remote sensors, was conducted in one of the most dangerous parts of the high Himalaya and one of the researchers was killed in an accident while collecting the data.
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