And that could lead to water shortages for millions of people in Asia.
The Himalayas are also referred to as the ‘third pole’ of the earth. After the North and South Poles, the Asian mountains have the most glacial ice. It’s no surprise that this ice cream is now fading fast. But a new study has now found that Himalayan glaciers are really melting at lightning speed; they appear to shrink much faster than glaciers elsewhere in the world.
lightning fast
It’s a disturbing discovery. “Our findings clearly show that ice is now melting ten times faster than the average over the past few centuries,” said study researcher Jonathan Carrivick. “This acceleration has only occurred in recent decades and coincides with human-induced climate change.”
Study
The team used satellite images and digital elevation models to find out what the glaciers looked like some 400-700 years ago, during the Little Ice Age. The satellite images revealed ridges marking the former glacier boundaries. The researchers used the shape of these ridges to estimate the size of the former glacier and the height of the ice surface. By comparing the ‘reconstruction’ with the current glacier, the researchers managed to determine the volume – and therefore also the mass loss.
Mass Loss
The numbers don’t lie. The findings show that Himalayan glaciers have lost about 40 percent of their surface area since the Little Ice Age. During this period, no less than 390 km3 and 586 km3 of ice melted. To your imagination, that’s the equivalent of all the ice today in the Central European Alps, the Caucasus, and Scandinavia combined. The water created by this melt has led to a global sea level rise between 0.92 mm and 1.38 mm.
Lakes and debris
The researchers also find that Himalayan glaciers also seem to be losing ice where they flow into lakes. The number and size of these glacial lakes are increasing, which the researchers say may indicate a continued acceleration in mass loss. In addition, glaciers with significant amounts of natural debris also appear to be losing ice rapidly. “We should also take these factors into account when modeling glaciers,” says Carrivick.
Water shortage
The melting of the Himalayan glaciers is bad news for millions of local residents. For example, it could lead to water shortages for millions of people in Asia, the researchers warn. During the dry season, ice melt water is an important source that fills rivers such as the Ganges, Brahmaputra and Indus. At present, this increased meltwater acts as a buffer for the people living in the region. But if the Himalayan glacier continues to shrink, densely populated countries like India and Bangladesh could face water or food shortages within a few decades. In some parts of the third pole, this is even more of a concern than flooding. Especially in arid regions – think of the western Himalayas, Hindu Kush and Central Asia – the meltwater from glaciers is crucial for sustaining agriculture. Adaptation strategies are unfortunately limited. And that could lead to people eventually even being forced to move.
“People in the region are already witnessing changes greater than anything seen in centuries past,” said study researcher Simon Cook. “This research confirms that these changes are accelerating and having a significant impact; not only for the regions concerned, but also for entire nations.”
The Himalayas contain more than 40 peaks above 7000 meters and 9 peaks above 8000 meters. This includes the highest mountain in the world, Mount Everest. The study shows that climate change does not leave even these high-altitude areas on Earth cold. Previous studies have even predicted that a significant portion of Himalayan glacial ice will be gone by the end of the century.
Source material:
“Himalayan glaciers melting at ‘exceptional rate’– University of Leeds (via EurekAlert)
Image at the top of this article: Duncan Quincey, University of Leeds