The Himalayas, or Himalaya, is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the Earth's highest peaks, including the highest, Mount Everest; more than 100 peaks exceeding elevations of 7,200 m (23,600 ft) above sea level lie in the Himalayas.
In geology, a proglacial lake is a lake formed either by the damming action of a moraine during the retreat of a melting glacier, a glacial ice dam, or by meltwater trapped against an ice sheet due to isostatic depression of the crust around the ice. At the end of the last ice age about 10,000 years ago, large proglacial lakes were a widespread feature in the northern hemisphere.
Hubbard Glacier is a glacier located in Wrangell–St. Elias National Park and Preserve in eastern Alaska and Kluane National Park and Reserve in Yukon, Canada, and named after Gardiner Hubbard.
Teesta River is a 414 km (257 mi) long river that rises in the Pauhunri Mountain of eastern Himalayas, flows through the Indian states of Sikkim and West Bengal and subsequently enters Bangladesh through Rangpur division. In Bangladesh, it falls into Brahmaputra River which after meeting some other major rivers of the Bengal delta finally falls into the Bay of Bengal. It drains an area of 12,540 km2 (4,840 sq mi). In India, the Teesta flows through Mangan District, Gangtok District, Pakyong District, Kalimpong district, Darjeeling District, Jalpaiguri District, Cooch Behar districts and the cities of Rangpo, Jalpaiguri and Mekhliganj. In Bangladesh, it flows through Lalmonirhat District, Rangpur District, Kurigram District and Gaibandha District. It joins the Brahmaputra River at Phulchhari Upazila in Bangladesh. 305 km (190 mi) of the river lies in India and 109 km (68 mi) in Bangladesh. The Teesta is the largest river of Sikkim and second largest river of West Bengal after the Ganges.
A moraine-dammed lake, occurs when the terminal moraine has prevented some meltwater from leaving the valley. When a glacier retreats, there is a space left over between the retreating glacier and the piece that stayed intact which holds leftover debris (moraine). Meltwater from both glaciers seep into this space creating a ribbon-shaped lake due to the pattern of ice melt. This ice melt may cause a glacier lake outburst flood, leading to severe damage to the environment and communities nearby. Examples of moraine-dammed lakes include:
A glacial lake is a body of water with origins from glacier activity. These are lakes that are formed on or in ice, ponded by ice or occuring in ice-scraped rock basins are referred to as glacial lakes. when a glacier erodes the land and then melts, filling the depression created by the glacier.
Palcacocha is a glacier lake in the Andes mountain range of South America in northwestern Peru located in the Ancash Region, Huaraz Province.
A glacial lake outburst flood (GLOF) is a type of outburst flood caused by the failure of a dam containing a glacial lake. An event similar to a GLOF, where a body of water contained by a glacier melts or overflows the glacier, is called a jökulhlaup. The dam can consist of glacier ice or a terminal moraine. Failure can happen due to erosion, a buildup of water pressure, an avalanche of rock or heavy snow, an earthquake or cryoseism, volcanic eruptions under the ice, or massive displacement of water in a glacial lake when a large portion of an adjacent glacier collapses into it.
Bhote Koshi in Nepal and Poiqu in Tibet is the name given to the upper course of the Sun Kosi river. It is part of the Koshi River system in Nepal.
Moses Coulee is a canyon in the Waterville plateau region of Douglas County, Washington. Moses Coulee is the second-largest and westernmost canyon of the Channeled Scablands, located about 30 kilometres (19 mi) to the west of the larger Grand Coulee. This water channel is now dry, but during glacial periods, large outburst floods with discharges greater than 600,000 m3/s (21,000,000 cu ft/s) carved the channel. While it's clear that glacial floodwaters passed through and contributed to the erosion of Moses Coulee, the age of those waters, thus the origins of the coulee are less clear. No clear connection between the head of the coulee and major flood routes to the north, east, or west is known. Some researchers propose that floods from glacial Lake Missoula formed Moses Coulee, while others suggest that subglacial floods from the Okanogan Lobe incised the canyon. The mouth of Moses Coulee discharges into the Columbia River.
Grasshopper Glacier is located in Shoshone National Forest, in the US state of Wyoming on the east of the Continental Divide in the Wind River Range. Grasshopper Glacier is in the Fitzpatrick Wilderness, and is part of the largest grouping of glaciers in the American Rocky Mountains. The glacier flows north, and glacial runoff supplies water to Grasshopper Creek, flowing eventually into the Wind River. The glacier shares a glacial margin with Klondike Glacier, located to the south. The glacier is named for grasshoppers that have been found entombed in the ice.
A supraglacial lake is any pond of liquid water on the top of a glacier. Although these pools are ephemeral, they may reach kilometers in diameter and be several meters deep. They may last for months or even decades at a time, but can empty in the course of hours.
The Sunkoshi, also spelt Sunkosi, is a river that is part of the Koshi or Saptkoshi River system in Nepal. Sunkoshi has two source streams, one that arises within Nepal in Choukati, and the other more significant stream that flows in from Nyalam County in the Tibet region of China. The latter is called Bhote Koshi in Nepal and Matsang Tsangpo in Tibet. Due to the significant flows from Bhote Koshi, the Sun Koshi river basin is often regarded as a trans-border river basin.
The Lhonak River is a tributary of the Teesta River in the Indian state of Sikkim.
Imja Tsho is a glacial lake created after melt water began collecting at the foot of the Imja Glacier on the lower part of the glacier in the 1950s. A 2009 study described this lake of melt water as one of the fastest-growing in the Himalayas. Held in place by a terminal moraine, Imja Tsho threatens downstream communities with the potential for a glacial outburst flood.
The glaciers in Bhutan, which covers about 3 percent of the total surface area, are responsible for feeding all rivers of Bhutan except the Amochu and Nyere Amachu.
The lakes of Bhutan comprise its glacial lakes and its natural mountain lakes. Bhutanese territory contains some 2,674 high altitude glacial lakes and subsidiary lakes, out of which 25 pose a risk of GLOFs. There are also more than 59 natural non-glacial lakes in Bhutan, covering about 4,250 hectares (16.4 sq mi). Most are located above an altitude of 3,500 metres (11,500 ft), and most have no permanent human settlements nearby, though many are used for grazing yaks and may have scattered temporary settlements.
Lake Merzbacher is a moraine glacier lake located in east Kyrgyzstan between the north and south Engilchek Glaciers in the Tien Shan Mountains. It is often called the "Disappearing Lake" because it drains every year as the ice melts, often causing a glacial lake outburst flood. The lake was named after a German explorer, Gottfried Merzbacher, who led an expedition in the area in 1903. An ice dam prevents the lake from draining through the majority of the year however when a hole finally melts through the dam the lake drains within three days. When this happens, the lake's discharge can be up to 1000 m3 a second which causes destruction of infrastructure and creates major flooding downstream. It goes through this cycle of appearing, expanding and then draining annually.
Thulagi glacier is located in the catchment area of the Marshyangdi River basin in Nepal. A study by KfW, Frankfurt and the BGR, in cooperation with the Department of Hydrology and Meteorology of Nepal have identified it as a potentially dangerous glacier due to possibility of outburst of the lake created by the glacier.
On 4 October 2023, heavy rains caused the glacial South Lhonak lake in Sikkim, a state in northeastern India, to breach its banks, causing a glacial lake outburst flood. The flood reached the Teesta III Dam at Chungthang at midnight, before its gates could be opened, destroying the dam in minutes. Water levels downstream in the River Teesta rose by up to 20 feet (6.1 m), causing widespread damage.
