Formation conditions of supraglacial lakes on debris-covered glaciers in the Himalaya

Sakai, Akiko; Fujita, Koji

doi:10.3189/002214310791190785

Cited by 98 publications

(93 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, the rapid melting of glaciers (glacier retreat) has resulted in the formation and expansion of glacial lakes, giving birth to PDMDLs (Richardson and Reynolds, 2000;Randhawa et al, 2005;Bajracharya et al, 2009;Sakai and Fujita, 2010;Salerno et al, 2012;Benn et al, 2012). In the Chinese Himalayas, which have a boundary of Gar Zangbu-Mapam Yumco-Yarlung Zangbu to the north and the China-IndiaBhutan national boundaries to the south (Fig.…”

Section: Study Areamentioning

confidence: 99%

An approach for estimating the breach probabilities of moraine-dammed lakes in the Chinese Himalayas using remote-sensing data

Xian-bin

Liu

Ding

et al. 2012

Nat. Hazards Earth Syst. Sci.

105

View full text Add to dashboard Cite

Abstract. To make first-order estimates of the probability of moraine-dammed lake outburst flood (MDLOF) and prioritize the probabilities of breaching posed by potentially dangerous moraine-dammed lakes (PDMDLs) in the Chinese Himalayas, an objective approach is presented. We first select five indicators to identify PDMDLs according to four predesigned criteria. The climatic background was regarded as the climatic precondition of the moraine-dam failure, and under different climatic preconditions, we distinguish the trigger mechanisms of MDLOFs and subdivide them into 17 possible breach modes, with each mode having three or four components; we combined the precondition, modes and components to construct a decision-making tree of moraine-dam failure. Conversion guidelines were established so as to quantify the probabilities of components of a breach mode employing the historic performance method combined with expert knowledge and experience. The region of the Chinese Himalayas was chosen as a study area where there have been frequent MDLOFs in recent decades. The results show that the breaching probabilities (P ) of 142 PDMDLs range from 0.037 to 0.345, and they can be further categorized as 43 lakes with very high breach probabilities (P ≥ 0.24), 47 lakes with high breach probabilities (0.18 ≤ P < 0.24), 24 lakes with mid-level breach probabilities (0.12 ≤ P < 0.18), 24 lakes with low breach probabilities (0.06 ≤ P < 0.12), and four lakes with very low breach probabilities (p < 0.06).

show abstract

Section: Study Areamentioning

confidence: 99%

An approach for estimating the breach probabilities of moraine-dammed lakes in the Chinese Himalayas using remote-sensing data

Xian-bin

Liu

Ding

et al. 2012

Nat. Hazards Earth Syst. Sci.

105

View full text Add to dashboard Cite

show abstract

“…Some studies have characterized the small-scale glacier surface topography of debris-covered glaciers using field-based surveys (Iwata et al, 2000;Sakai and Fujita, 2010;Zhang et al, 2011), while other studies focused on understanding patterns at the mountain-range scale (Scherler et al, 2011;Bolch et al, 2012;Gardelle et al, 2013;Racoviteanu et al, 2014). Glacier shrinkage and mass loss has been documented in the Himalaya concomitantly with an increase in debris cover Nuimura et al, 2012).…”

Section: Introductionmentioning

confidence: 99%

Spatial patterns in glacier characteristics and area changes from 1962 to 2006 in the Kanchenjunga–Sikkim area, eastern Himalaya

et al. 2015

View full text Add to dashboard Cite

Abstract. This study investigates spatial patterns in glacier characteristics and area changes at decadal scales in the eastern Himalaya -Nepal (Arun and Tamor basins), India (Teesta basin in Sikkim) and parts of China and Bhutan -based on various satellite imagery: Corona KH4 imagery, Landsat 7 Enhanced Thematic Mapper Plus (ETM+) and Advanced Spaceborne Thermal Emission Radiometer (ASTER), QuickBird (QB) and WorldView-2 (WV2). We compare and contrast glacier surface area changes over the period of 1962-2000/2006 and their dependency on glacier topography (elevation, slope, aspect, percent debris cover) and climate (solar radiation, precipitation) on the eastern side of the topographic barrier (Sikkim) versus the western side (Nepal).Glacier mapping from 2000 Landsat ASTER yielded 1463 ± 88 km 2 total glacierized area, of which 569 ± 34 km 2 was located in Sikkim and 488 ± 29 km 2 in eastern Nepal. Supraglacial debris covered 11 % of the total glacierized area, and supraglacial lakes covered about 5.8 % of the debris-covered glacier area alone. Glacier area loss (1962 to 2000) was 0.50 ± 0.2 % yr −1 , with little difference between Nepal (0.53 ± 0.2 % yr −1 ) and Sikkim (0.44 ± 0.2 % yr −1 ). Glacier area change was controlled mostly by glacier area, elevation, altitudinal range and, to a smaller extent, slope and aspect. In the Kanchenjunga-Sikkim area, we estimated a glacier area loss of 0.23 ± 0.08 % yr −1 from 1962 to 2006 based on high-resolution imagery. On a glacier-by-glacier basis, clean glaciers exhibit more area loss on average from 1962 to 2006 (34 %) compared to debris-covered glaciers (22 %). Glaciers in this region of the Himalaya are shrinking at similar rates to those reported for the last decades in other parts of the Himalaya, but individual glacier rates of change vary across the study area with respect to local topography, percent debris cover or glacier elevations.

show abstract

“…Benn et al, 2012), and ends with the failure of a moraine dam and the generation of a GLOF (Benn and Owen, 2002). By comparison, many debris-covered glacier tongues in the region (Hambrey et al, 2009;Benn et al, 2012), and in the wider Himalaya (Sakai and Fujita, 2010) currently host a network of supraglacial ponds, or are undergoing a transition to fully-formed moraine-dammed lake development. The progression of the Chukhung Glacier-moraine-dam complex to the end of this continuum is explained by the nature of its formation; that it proceeded along an alternative and accelerated pathway associated with comparatively steep and largely debris-free parent glaciers (Figure 11).…”

Section: Regional and Global Contextmentioning

confidence: 99%

Reconstructing historic Glacial Lake Outburst Floods through numerical modelling and geomorphological assessment: Extreme events in the Himalaya

Westoby

Glasser

Hambrey

et al. 2014

Earth Surf Processes Landf

View full text Add to dashboard Cite

Recession of high-mountain glaciers in response to climatic change frequently results in the development of morainedammed glacial lakes. Moraine dam failure is often accompanied by the release of large volumes of water and sediment, termed a Glacial Lake Outburst Flood (GLOF). Chukhung Glacier is a small (~3 km 2 ) receding valley glacier in Mt. Everest (Sagarmatha) National Park, Nepal. Unlike many Himalayan glaciers, which possess a thick mantle of supraglacial debris, its surface is relatively clean. The glacier terminus has receded 1.3 km from its maximum Holocene position, and in doing so provided the space for an icecontact moraine-dammed lake to develop. The lake had a maximum volume of 5.5 × 10 5 m 3 and drained as a result of breaching of the terminal moraine. An estimated 1.3 × 10 5 m 3 of material was removed from the terminal moraine during breach development. Numerical dam-breach modelling, implemented within a Generalised Likelihood Uncertainty Estimation (GLUE) framework, was used to investigate a range of moraine-dam failure scenarios. Reconstructed outflow peak discharges, including failure via overtopping and piping mechanisms, are in the range 146-2200 m 3 s -1 . Results from two-dimensional hydrodynamic GLOF modelling indicate that maximum local flow depths may have exceeded 9 m, with maximum flow velocities exceeding 20 m s -1 within 700 m of the breach. The floodwaters mobilised a significant amount of material, sourced mostly from the expanding breach, forming a 300 m long and 100 m wide debris fan originating at the breach exit. moraine-dam. These results also suggest that inundation of the entire floodplain may have been achieved within ten minutes of initial breach development, suggesting that debris fan development was rapid. We discuss the key glaciological and geomorphological factors that have determined the evolution of a hazardous moraine-dammed lake complex and the subsequent generation of a GLOF and its geomorphological impact.

show abstract

Formation conditions of supraglacial lakes on debris-covered glaciers in the Himalaya

Cited by 98 publications

References 10 publications

An approach for estimating the breach probabilities of moraine-dammed lakes in the Chinese Himalayas using remote-sensing data

An approach for estimating the breach probabilities of moraine-dammed lakes in the Chinese Himalayas using remote-sensing data

Spatial patterns in glacier characteristics and area changes from 1962 to 2006 in the Kanchenjunga–Sikkim area, eastern Himalaya

Reconstructing historic Glacial Lake Outburst Floods through numerical modelling and geomorphological assessment: Extreme events in the Himalaya

Contact Info

Product

Resources

About