Temporal Variation of Glacier Melting Rate of Helheim and Gangotri Glaciers Using Sentinel 1A Images

Glaciers in the central Himalayas are important water resources for the downstream habitants, and accelerating melting of the high mountain glaciers speed up with continuous warming. We summerized the geodetic glacier surface elevation changes (Dh) by 6 data sets at different time periods during 1974-2016 in RongbukCatchment(RC) on the northern slope of Mt. Qomolangma (Mt. Everest) in the Central Himalayas. The result showed that glacier Dh varied with altitude and time, from -0.29 &#177; 0.03m a-1 in 1974-2000, to -0.47 &#177;0.24 m a-1 in 1974-2006,and -0.48 &#177;0.16 m a-1 in 1974-2012. Dh increased to -0.60 &#177; 0.20 m a-1 in 2000-2012, then decreased to-0.46 &#177; 0.24 m a-1 in 2000-2014, and by -0.49 &#177; 0.08 m a-1 in 2000-2016, showing a diverse rate being up - down- a little up. However, it generally presented a similar glacier thinning rate by -0.46~-0.49 m a-1 in the last four decades since 1970s in RC according to Dh1974-2006, Dh1974-2012, Dh2000-2014, and Dh2000-2016. Local meteorological observations revealed that, to a first order, the glacier thinning rate was kept the same pace with the number of annual melting days (MD). In spite of the obviously arising summer air temperature (TS) in 2000-2014, a slowdown glacier melting rate by -391 mm w.e.a-1 occurred in 2000-2014 because of less melting days with more precipitation and less annual mean temperature(Tm). It shows that MD is another important indicator and controlling factor to evaluate or to estimate glacier melting trend, especially in hydrological or climate modeling.

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A 10 yr record of black carbon and dust from Mera Peak ice core (Nepal): variability and potential impact on Himalayan glacier melting

The Cryosphere Discussions ◽

10.5194/tcd-7-6001-2013 ◽

2013 ◽

Vol 7 (6) ◽

pp. 6001-6042 ◽

Cited By ~ 4

Author(s):

P. Ginot ◽

M. Dumont ◽

S. Lim ◽

N. Patris ◽

J.-D. Taupin ◽

...

Keyword(s):

Black Carbon ◽

Ice Core ◽

Melting Rate ◽

Precipitation Pattern ◽

Precipitation Regime ◽

Mass Fluxes ◽

Glacier Melting ◽

Surface Snow ◽

Joint Contribution ◽

The Impact

Abstract. A shallow ice core of the southern flank of Nepalese Himalaya range was extracted from the summit of Mera Peak at 6376 m a.s.l. in Nepal. From this core, we have reconstructed the seasonal deposition fluxes of dust and refractory black carbon (rBC) since 1999. This archive presents well preserved seasonal cycles based on monsoonal precipitation pattern. According to the seasonal precipitation regime, 80% of the annual precipitation between June and September, we estimated the surface snow concentrations evolution for these aerosols. The analyzes reveals that mass fluxes are a few orders of magnitude higher for dust (10.2±2.5 g m−2 yr−1) that for rBC (3.2±1.2 mg m−2 yr−1).These data were used to simulate the surface snow albedo changes with time and the induced potential melting related to these impurities. The potential melting associated to joint dust and rBC can reach 660 kg m−2 yr−1, and 220 kg m−2 yr−1 for rBC only under some assumptions. Compared to the melting rate measured by mass and energy balance at 5400 m a.s.l. on Mera glacier, close to the equilibrium altitude, the impact of rBC represents less than 7% of annual potential melting while the joint contribution of dust and rBC of the surface melting represents a maximum 18%. Furthermore, over this 10 yr time span, the fluxes variability in the ice core signal is rather reflecting the variability of the monsoon signal than that of emission intensity.

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Temperate Mountain Glacier-Melting Rates for the Period 2001–30: Estimates from Three Coupled GCM Simulations for the Greater Himalayas

Journal of Applied Meteorology and Climatology ◽

10.1175/jam2499.1 ◽

2007 ◽

Vol 46 (6) ◽

pp. 890-899 ◽

Cited By ~ 9

Author(s):

Diandong Ren ◽

David J. Karoly ◽

Lance M. Leslie

Keyword(s):

General Circulation ◽

Climate Model ◽

Circulation Model ◽

Melting Rate ◽

Geophysical Fluid Dynamics Laboratory ◽

Regional Warming ◽

Mountain Glacier ◽

The North ◽

Glacier Melting ◽

Energy Balance Approach

Abstract The temperate glaciers in the greater Himalayas (GH) and the neighboring region contribute to the freshwater supply for almost one-half of the people on earth. Under global warming conditions, the GH glaciers may melt more rapidly than high-latitude glaciers, owing to the coincidence of the accumulation and ablation seasons in summer. Based on a first-order energy balance approach for glacier thermodynamics, the possible imposed additional melting rate was estimated from three climate simulations using the Geophysical Fluid Dynamics Laboratory Global Coupled Climate Model version 2.1 (GFDL-CM2.1), the Model for Interdisciplinary Research on Climate 3.2, high-resolution version (MIROC3.2-hires), and the Met Office’s Third Hadley Centre Coupled Ocean–Atmosphere General Circulation Model (HadCM3). The simulations were carried out under the Special Report on Emissions Scenarios (SRES) A1B scenario. For the 30-yr period of 2001–30, all three CGCMs indicate that the glacial regions most sensitive to regional warming are the Tianshan–Altai Mountains to the north and Hengduan Mountains to the south. A map of potential melting was produced and was used to calculate the glacier-melting speed, yielding an additional spatially averaged glacier depth reduction of approximately 2 m for the 2001–30 period for those areas located below 4000 m. Averaged over the entire GH region, the melting rate is accelerating at about 5 mm yr−2. The general circulation over the GH region was found to have clear multidecadal variability, with the 30-yr period of 2001–30 likely to be wetter than the previous 30-yr period of 1971–2000. Considering the possible trend in precipitation from snow to rain, the actual melting rates of the GH glaciers may even be larger than those obtained in this research.

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Combination of UAV and terrestrial photogrammetry to assess rapid glacier evolution and conditions of glacier hazards

10.5194/nhess-2017-198 ◽

2017 ◽

Cited By ~ 2

Author(s):

Davide Fugazza ◽

Marco Scaioni ◽

Manuel Corti ◽

Carlo D'Agata ◽

Roberto Sergio Azzoni ◽

...

Keyword(s):

Point Clouds ◽

Melting Rate ◽

Aerial Survey ◽

Thickness Change ◽

Glacier Tongue ◽

Glacier Terminus ◽

Digital Elevation ◽

Glacier Melting ◽

Uav Images ◽

Terrestrial Photogrammetry

Abstract. Tourists and hikers visiting glaciers all year round face hazards such as the rapid formation of collapses at the terminus, typical of such a dynamically evolving environment. In this study, we analysed potential hazards of the Forni glacier, an important geo-site located in Stelvio Park (Italian Alps), by describing local surface features and evaluating the glacier melting rate. The analyses were based on point clouds and digital elevation models (DEMs) from two separate surveys of the glacier tongue carried out in 2014 and 2016 with Unmanned Aerial Vehicles (UAVs), terrestrial photogrammetry (only in 2016) and a DEM obtained in 2007 from an aerial survey. On the area covered by the 2016 survey, average glacier thinning rates of −4.15 ma−1 were found in 2007-2016, while the mean thickness change of the glacier tongue in 2014–2016 was −10.40 ± 2.60 m. UAV-based DEMs were thus found to be sufficiently accurate with respect to the rates of glacier down-wasting, while terrestrial photogrammetry allowed the reconstruction of the glacier terminus, presenting several vertical and sub-vertical surfaces whose modelling was difficult to obtain from airborne UAV images. The integration of UAV and terrestrial photogrammetry provided a detailed and accurate 3D model of the glacier tongue, which we used to identify hazard areas.

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Climate Change Impacts on Water Resources of Nepal with Reference to the Glaciers in the Langtang Himalayas

Journal of Hydrology and Meteorology ◽

10.3126/jhm.v6i1.5489 ◽

1970 ◽

Vol 6 (1) ◽

pp. 58-65 ◽

Cited By ~ 5

Author(s):

Narayan Prasad Chaulagain

Keyword(s):

Climate Change ◽

Water Resources ◽

Climate Change Impacts ◽

Melting Rate ◽

Mass Model ◽

Adverse Impacts ◽

Glacier Melting ◽

Glacier Ice ◽

Hydrological Station ◽

Impacts Of Climate Change

The impacts of climate change on water resources of Nepal with reference to snow and glacier were assessed. Empirical glacier mass model was applied to all the glaciers upstream of the Kyangjing hydrological station in the Langtang Valley in the Nepal Himalayas in order to assess their sensitivity to the increases in temperature. The analysis has revealed that the glaciers in the study area of the Nepal Himalayas are shrinking rapidly and may disappear within less than two centuries, if the current glacier melting rate continues. Most of the glaciers will disappear within 3-4 decades; there may be only 24% of the present glacier-ice reserve left in the study basin of the Nepal Himalayas by 2100 AD even without any further warming which may result in serious adverse impacts on the water resources of Nepal.Key Words: Climate Change; Water Resources; Nepal Himalayas; GlaciersDOI: http://dx.doi.org/10.3126/jhm.v6i1.5489 Journal of Hydrology and Meteorology, Vol. 6, No. 1 58-65

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