The Himalayan glaciers are melting at an alarming rate!


Scientists usually refer to the Himalayas as « Third pole ». Because its glaciers contain the third largest amount of ice in the world. And today, researchers are telling us that, under the effect of anthropogenic global warming, these glaciers are melting at a record speed. In particular threatening the water supply of millions of people.

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All over the world, ice is melting. A consequence of global warming anthropogenic. And researchers from the University of Leeds (United Kingdom) tell us today that the glaciers of the Himalayas, in particular, are melting at a speed which they themselves qualify as exceptional. Over the past few decades, they have lost ice ten times faster than the average since their last major expansion during the Little Ice Age between 400 and 700 years ago.

The researchers base this on a reconstruction of nearly 15,000 Himalayan glaciers. While at their peak, they covered an area of ​​some 28,000 square kilometers, today they only cover about 19,600 square kilometers. That is to say an ice loss of no less than 40% in area. At the same time, they also lost in volumefrom 596 cubic kilometers to just 309 cubic kilometers. A loss equivalent to all the ice of the Alps, the Caucasus and Scandinavia combined.

A cast with heavy consequences

The researchers say that the loss of ice is even more marked in the eastern regions. At issue: different weather patterns. The source is also more marked for glaciers with large amounts of natural debris on their surface. By volume, they are responsible for nearly 50% of the ice loss while they account for only about 7.5% of the total glaciers. But the loss of ice is also greater for glaciers that end up in lakes. Thus, with an increase in the number and size of these Himalayan lakes, the rate of melting could accelerate further.

If this melting of the Himalayan glaciers has already caused a rise in sea level of about 1 millimeter, it is mainly for thewater supply et en energy hundreds of millions of people in the region that scientists worry about. Because the acceleration of the phenomenon will have important implications for the main river systems of the Himalayas. The inhabitants of the region are already seeing changes that seem to be accelerating.

Himalayas: two-thirds of glaciers will melt by the end of the century

The « third land pole », which includes the entire Himalayan chain, will experience an unprecedented melting, with consequences for nearly two billion inhabitants. Mountain areas are in fact particularly sensitive to global warming.

Article by Celine Deluzarche published on 02/06/2019

« It’s the climate crisis you haven’t heard of », Says Philippus Wester, head ofa study led by Icimod, an intergovernmental organization based in Kathmandu (Nepal). According to’International Center for Integrated Mountain Development (Icimod), two thirds of the glaciers of the Hindu Kush and the Himalayas (HKH) could to melt by the end of the century if the planet remains on the same trajectory ofemissions from greenhouse gas.

Global warming and pollution: the deadly cocktail for glaciers

Qualified as the « third pole » by scientists for its gigantic ice reserves, this mountainous region, extending over 3,500 km and crossing eight countries, is likely to see its glaciers largely disappear. Even by limiting the temperature rise to the limit of 2.1 ° C as provided for in the Paris Agreement, a third will have melted by 2100, experts warn.

And if emissions continue at the same rate, with an increase of 5 ° C, two-thirds of the glaciers will have vanished. Although formed 70 million years ago, they are extremely sensitive to climate change. Since the 1970s, a decline and thinning of snow cover have already been observed. The phenomenon is aggravated by the pollution coming from the plains of India which deposit black dust on glaciers, accelerating their melting.

A billion people in danger

The report, unprecedented in its scope, took five years of work and brings together the views of 350 researchers and experts from 22 countries and 185 organizations. He highlights the severe consequences of this melting for the 250 million inhabitants of these mountains and the 1.65 billion who live in the river basins downstream. The glaciers of HKH thus supply ten of the most important river networks of the world, whose Gange, Indus, Yellow, Mekong and Irrawaddy.

« An increase in the number and size of glacial lakes will result in an influx of water into major rivers, which could lead to flooding and destruction of crops. “, Warns the study. The increase in debit Ganges and Brahmaputra will also force changes in agriculture. More frequent landslides and floods  » endanger more than a billion people », Warns Icimod.

The Alps, too, could lose 90% of their glaciers

All over the world, mountains are meltingeye. The glaciers of the French Alps have lost 25% in 12 years and their melting is three times faster since 2003 compared to the previous period (1986-2003), according to the Laboratory of Glaciology and Environmental Geophysics (LGGE) of Grenoble. Depending on the extent of the warming, 50 to 90% of alpine glaciers could disappear by 2100. In the Pyrénées, half of the glaciers have melted in the past 35 years and the trend seems to be accelerating. According to the latest bulletin of World Glacier Monitoring Service (WGMS), glaciers around the world have lost an average of 0.9 meters, the water equivalent of mass per year, in the years 2013-2016, against 0.2 meters for the decade 1981-1990.

Himalayan glaciers: the melting trend is confirmed

Article by Bruno Scla published on 12/06/2011

The International Center for Integrated Mountain Development (Icimod) published, on the sidelines of the Durban summit, a summary on the state of the glaciers in the Himalayas. Overall they tend to melt like snow at soleil.

In  » off  » from durban summit, the International Center for Integrated Mountain Development (Icimod) published three reports on 4 December concerning the glaciers, the snow and the climate change in the Himalayas. These reports highlight in particular an important melting of the glaciers, which could have strong repercussions on the inhabitants of the various valleys.

These publications constitute the most complete synthesis of the state of glaciers and you coat snowy on the peaks of the Himalayas, in the region ofHindu Kush-Himalaya, which encompasses the majority of the Himalayan peaks.

Fifty-four thousand glaciers in the Himalayas

The first object of the work of this organization was to identify the glaciers in the region. They number 54,000 (or 30% of the whole world) and cover an area of ​​60,000 km² for about 6,000 km3 of ice. But among this accumulation of glaciers – which is why the region is called the third pole – only ten have been studied precisely, and it is on these that the synthesis of Icimod has focused.

And the results speak for themselves. Over the past thirty years, the area covered by glaciers in Bhutan has decreased by 22%, and 21% in Nepal. Additionally, Icimod experts noted a significant drop in mass balance – the difference between accumulation andablation. Between the periods 1980-2000 and 1996-2005, the rate of glacier melting thus doubled overall, although this rate varies quite strongly depending on the zone considered.

More than 1 billion inhabitants dependent on glaciers

If the Icimod report does not put forward any date for the disappearance of Himalayan glaciers, it nevertheless confirms a trend: the melting accelerates.

The members of Icimod are also worried about the populations who live in the valleys. Glaciers indeed feed ten major rivers – the Amu-Daria, Indus, Ganges, Brahmaputra, Irrawaddy, Salouen, Mekong, Yangtze, Hunag He and Tarim – including 1, 3 billion inhabitants depend. A decrease in water supply would threaten agriculture and biodiversity and could cause a water stress, that is to say a greater demand for water than the supply.

We hope that these results will be heard by the climate negotiators meeting in Durban.

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