Potential Proglacial Lake Discovered on Drang Drung Glacier

Image of the breathtaking Drang Drung Glacier from 2012 (Source: Poonam Agarwal/Flickr).

In the northwest reaches of the Himalayas, most glaciers, with a few exceptions in the Karakorum, are showing signs of rapid retreat due to climate change. With long-term climate projections indicating the rise of local minimum temperatures by over 4 degrees Celsius above pre-industrial levels by 2100, the formation of glacial lakes is predicted as the glaciers melt, which could, in turn, have serious socio-environmental impacts.

One glacier already under threat, the Drang Drung, located in the Zanskar region of Jammu and Kashmir, is the focus of a recent study published by Irfan Rashid and Ulfat Majeed in Environmental Earth Sciences. It has shrunk over a seventh of its size in the last 46 years from 1971 to 2017. Using the latest earth observation data, Rashid and Majeed discovered the formation of a potential proglacial lake that began in 2008 and has been growing exponentially since 2014. In fact, within the last four years, the rate of retreat at the snout of the glacier appears to have “radically accelerated,” the authors note.

Tucked in a high-altitude, cold, and arid region, the Drang Drung glacier is a massive ice glacier at a whopping length of 23.3 kilometers, almost 15 miles long. Its runoff contributes as a major source of the Zanskar River, a tributary of the mighty Indus River. Additionally, the glaciers of the region play a crucial role in sustaining the area’s economy and energy supply.

But, to date, analysis on the evolution of glacial lakes and their hazardous potential in the northwest Himalayan region is limited. “Formation and behavior of proglacial lakes over the Jammu and Kashmir region have not been studied in much detail, and hence this region remains a data void,” Rashid explained to GlacierHub.

Despite studies in recent years to account for glacial recession and catalog the formation of glacial lakes in the Himalayas as a whole, data on glacial lake evolution, mass balance, snow cover dynamics, and other factors remain scanty. The study sought to provide a more comprehensive assessment of changes in the Drang Drung area. The dangerously high retreat rate in India’s Kashmir compared to other high-altitude glacierized regions in Asia indicates with high probability that this substantial home to glaciers could be lost before the end of the century, according to the article.

With other related implications in mind like streamflows, hydropower capabilities, and tourism, the study highlighted the importance of evaluating the regional changes to the water resources so that “policymakers are equipped with scientifically robust knowledge that will help in framing policies aimed to sustain the ever depleting water resources in the region.”

Toward this aim, Rashid and Majeed used a Glacier Bed Topography (GlabTop) model to estimate Drang Drung’s glacial thickness and glacier bed overdeepenings (characteristics of valleys and basins eroded by glaciers).

“These overdeepenings in the glacier bed provide an idea about the likelihood of formation of proglacial lakes in the future given the retreating behavior of glaciers,” said Rashid. Being able to input meteorological and climate projections, the researchers were able to simulate what portions of the glacier have the potential to hold water and form lakes as the glacier retreats in upcoming years.

Their conclusions were alarming. Since 1971, the glacier has receded a total of over 925 meters, the length of eight Olympic-sized soccer fields stretched out together. Over the past 46 years, the team distinguished three retreat rates: from 1971 to 2000, the glacier retreated at 22.76 meters a year; between 2000 and 2014, the rate slowed to 6.07 meters a year; and since 2014, the pace accelerated rapidly to 60 meters a year, a length just short of two NBA-size basketball courts.

In terms of the new lake, the team’s assessment revealed that the lake’s rapid growth has a potential peak discharge capacity between 2,343 and 2,667 cubic meters of water per second. For a bit of context on this capacity, in 2013, the outburst of the Chorabari lake in Kedarnath (a devastating flood that killed more than 6,000 people and destroyed critical infrastructure including 30 hydropower plants) released a peak discharge of only 783 cubic meters a second. This could mean that the burst of this new moraine-dammed proglacial lake at Drang Drung has the potential to release 3.5 times more discharge than the fatal 2013 outburst, increasing the vulnerability of communities living downstream.

On top of this finding, another portion of the team’s analysis indicated that temperature warming under current projections could lead to the formation of up to 76 new lakes in the region, although this remains entirely dependent of the future retreating behavior of Drang Drung. In addition, with a massive storage capacity following melting, the potential peak discharge rates were estimated to be at a whopping 35,000 to 48,000 cubic meters of water per second.

Despite the increased vulnerability discovered by the researchers, Rashid is unaware of any disaster risk preparedness initiatives to support the vulnerable communities.

“I do not think the communities have been sensitized with the implications of proglacial lakes and their vulnerability to GLOFs [glacial lake outburst floods],” Rashid told GlacierHub. “Since no such disaster has been reported in the regions, the policymakers seem to be in deep slumber. There are at least four such lakes that have constantly been growing in size since the past two decades in the Zanskar region only, and nobody seems to bother about it. I think the perception and response could be altogether different in case, and God forbid, a GLOF strikes the region.”

For the sake of the surrounding communities, the authors hope a major disaster isn’t the first motivator to get policymakers to discuss the necessary warning systems and other measures to protect the local people against the rising risks of climate change.

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If we thought reducing glaciers is only in Antarctica or North Pole and other northern hemispheric Regions, than we are absolutely wrong, this one is The Drang-Drung Glacier, a mountain glacier near the Pensi La mountain pass at the Kargil – Zanaskar Road in the Kargil district of Jammu and Kashmir, India. The Drang-Drung Glacier is likely to be the largest glacier in Ladakh other than the Siachen Glacier in the Karakoram Range. If you talk to the locals, you could gauge the scale of reduction in past few years. This was clicked in August 2013 and locals told us that few years back we could hardly see the open land, I have seen a photograph clicked by a friend of mine this year and the glaciers have noticeably reduced even further. Hope with the active awareness, we humans contribute to the lesser damage to our environment in future and bring the nature back to it normalcy before it perishes for the future generation and better good of Mother Earth. #IncredibleIndia #MountainTales #Mountains #NatgeoCreative #NatGeo #Nature #Zanskar#Ladakh #Glaciers #Environment #Nikon #NoPollution #NatGeoTravel #LonelyPlanetIndia #LonelyPlanet #MountainTales #LifeLessons #_oye #NoFilters #ThroughANewLensContest #skyView -#arielview #Ladakh #India #incredibleindia #Landscape_captures #igs_asia #ig_india #igs_world #Stunning_shots #ig_worldphotos #d810 #Nikon @lonelyplanetindia @paulnicklen

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Flooding Glacial Lakes in Chile

It is a peaceful experience to walk near the glacial lake near Colonia Glacier, one of several prominent glacier lakes in Patagonia, Chile. The breeze on the lake helps you relax as you look out on the distant glaciers. In such a tranquil setting, it is hard to imagine that a glacial lake outburst flood (GLOFs) could pose a threat to the area. However, GLOFs have become a significant but poorly understood hazard of a warming global climate.

Glacial Lake near Colonia Glacier (source: Ben Price / Flickr).

The truth is, melting Colonia Glacier, located in the Northern Patagonian Ice Field, Chile, has caused dozens of GLOFs over the years. The lake near Colonia Glacier, Cachet II, has been drained frequently after unexpected floodings. The people living nearby are under constant threat of a sudden flood, which could completely destroy homes and livelihoods.

Actually now, in the Chilean and Argentinean Andes, recent research by project member Pablo Iribarren Anacona has identified at least 31 glacial lakes have failed since the eighteenth century, producing over 100 GLOF events.

Comparison of 1987 and 2015 Landsat images indicating Colonia Glacier retreat and the development of a new lake at the terminus (source: Mauri Pelto/AGU).

“These lakes can be dangerous, and we need to take action,” Alton Byers, a geologist at the University of Colorado, told GlacierHub.

A group of scientists concerned about GLOF risk have initiated a project, “Glacier Hazards in Chile,” which aims to answer key questions concerning past, present and future glacial hazards in Chile. One of the members is Ryan Wilson, a glaciologist at Aberystwyth University in the United Kingdom.

Glacier lake outburst flooding (source: Pieter Edelman/Flickr).

“The project will assess the changing magnitude, frequency, and distribution of different glacial hazards in Chile under current and future global climate change,” Wilson explained to GlacierHub. At the moment, Wilson and the other researchers are focusing on understanding the processes that govern the development of GLOFs in Chile.

The fieldwork of Wilson and his team was recently featured in Science. The them held a workshop at Aberystwyth University in July 2016, during which they discussed progress on their Chilean fieldwork, glacial lake mapping, glacial hazard assessment, outburst flood modeling and climate modeling.

Left to right: Marius Schaefer, Ryan Wilson, Neil Glasser, John Reynolds, Sarah Shannon, and Pablo Irribaren (source: Glacial Hazards in Chile).

To assess GLOFs and GLOF risk, the team compiled a glacial lake inventory for the central and Patagonian Andes (1986 – 2016). Wilson said they used remote-sensing and fieldwork to find past GLOF sites around the major icefields, satellite glaciers and snow-and ice-capped volcanoes of Chile.

A storm is brewing (source: Joost van Veen/Flickr).

“We have managed to use this lake inventory to inform field campaigns in February to two interesting glacial lake sites in Chile,” Wilson said. “We conducted aerial drone surveys and collected lake bathymetry data.” The team will next analyze flood hydrographs (a graph showing the rate of flow versus time past a specific point in a river) of selected former GLOFs and use these to establish the patterns of downstream impacts. They are proud of their work so far, which they hope to publish soon.

The team carrying out a topographic survey in the Colonia Valley (source: Glacial Hazards in Chile).

Using the inventory across Chile, the team and local community  are able to assess the potential damage GLOFs can cause. Wilson et al. plan to “conduct numerical simulations of downstream impacts for selected potential GLOF sites using physically-based numerical flood models.”

In collaboration with Chilean partners, this research will be used to develop early warning systems and raise awareness about quantified GLOF risks. Glacial hazards have threatened various commercial and governmental stakeholders across Chile, making GLOFs a pressing priority.

Lalo, a local farmer who raises livestock, is under the threat of GLOFs (source: NRDC).

The ultimate goal of the project is to provide a framework that can be applied to other lower income countries, since GLOFs pose threats in multiple countries.

“We will make recommendations for GLOF hazard assessment protocols and mitigation strategies in lower income countries globally,” Wilson told GlacierHub.

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