Mass Balance of Four Cirque Glaciers in the Torngat Mountains of Northern Labrador, Canada

Abstract The net mass balance of four small cirque glaciers (0.7–1.4 km2) in the Torngat Mountains of northern Labrador was measured for 1981–84, allowing three complete mass-balance years to be calculated. The two largest glaciers experienced positive mass-balance conditions in 1982 while all the glaciers were negative in 1983. The temporal pattern relates directly to general climatic conditions, in particular winter snowfall. Spatial variations of mass balance on the glaciers are the result of several factors including altitude, extent of supraglacial debris cover, slope, proximity to side and backwalls of the enclosing cirque, and the height of the backwall above the ice surface. Abraham Glacier, the smallest studied and with consistently the largest negative mass balance (–1.28 m in 1983), re-advanced an average of 1.2 m each year between 1981 and 1984. Mean equilibrium-line altitude (ELA) for the four glaciers is 1050 m, varying substantially from one glacier to another (+240 to –140 m) and from year to year (+60 to –30 m).

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High-resolution ice thickness and bed topography of a land-terminating section of the Greenland Ice Sheet

Earth System Science Data Discussions ◽

10.5194/essdd-7-129-2014 ◽

2014 ◽

Vol 7 (1) ◽

pp. 129-148 ◽

Cited By ~ 4

Author(s):

K. Lindbäck ◽

R. Pettersson ◽

S. H. Doyle ◽

C. Helanow ◽

P. Jansson ◽

...

Keyword(s):

Mass Balance ◽

Sea Level ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Airborne Radar ◽

Ice Thickness ◽

Equilibrium Line Altitude ◽

Bed Topography ◽

Ice Surface ◽

Ice Sheet Dynamics

Abstract. We present ice thickness and bed topography maps with high spatial resolution (250 to 500 m) of a and-terminating section of the Greenland Ice Sheet derived from combined ground-based and airborne radar surveys. The data have a total area of ~12000 km2 and cover the whole ablation area of the outlet glaciers of Isunnguata Sermia, Russell, Leverett, Ørkendalen and Isorlersuup up to the long-term mass balance equilibrium line altitude at ~1600 m above sea level. The bed topography shows highly variable subglacial trough systems, and the trough of the Isunnguata Sermia Glacier is over-deepened and reaches an elevation of several hundreds of meters below sea level. The ice surface is smooth and only reflects the bedrock topography in a subtle way, resulting in a highly variable ice thickness. The southern part of our study area consists of higher bed elevations compared to the northern part. The covered area is one of the most studied regions of the Greenland Ice Sheet with studies of mass balance, dynamics, and supraglacial lakes, and our combined dataset can be valuable for detailed studies of ice sheet dynamics and hydrology. The compiled datasets of ground-based and airborne radar surveys are accessible for reviewers (password protected) at doi.pangaea.de/10.1594/pangaea.830314 and will be freely available in the final revised paper.

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A regression model for the mass-balance distribution of the Vatnajökull ice cap, Iceland

Annals of Glaciology ◽

10.3189/172756403781815447 ◽

2003 ◽

Vol 37 ◽

pp. 189-193 ◽

Cited By ~ 10

Author(s):

Guðefinna Aðalgeirsdóttir ◽

G. Hilmar Gudmundsson ◽

Helgi Björnsson

Keyword(s):

Linear Regression ◽

Regression Model ◽

Mass Balance ◽

Surface Mass Balance ◽

Negative Mass ◽

Equilibrium Line Altitude ◽

Surface Mass ◽

Ice Cap ◽

Maximum Value ◽

Slope Direction

AbstractA non-linear regression model describing the mass-balance distribution of the whole Vatnajökull ice cap, Iceland, for the years 1992–2000 is presented. All available data from some 40 locations over this 9 year period were used to determine the parameters of the model. The regression model uses six adjustable parameters which all have a clear physical interpretation. They are the slope, direction and the height of the equilibrium-line altitude (ELA) plane, two altitude mass-balance gradients, and a maximum value of the surface mass balance. It is found that the temporal variation of the observed mass-balance distribution can be accurately described through annual shifts of the ELA. Annual shifts in ELA are on the order of 100 m, which is of the same magnitude as the change expected to be caused by the climate variation predicted during the next decades. A slight trend towards a more negative mass balance is detected during this 9 year period.

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Mass Balance of “Vesper” Glacier, Washington, U.S.A.

Journal of Glaciology ◽

10.1017/s0022143000015380 ◽

1981 ◽

Vol 27 (96) ◽

pp. 271-282 ◽

Cited By ~ 3

Author(s):

David P. Dethier ◽

Jan E. Frederick

Keyword(s):

Nineteenth Century ◽

Mass Balance ◽

Cascade Range ◽

Equilibrium Line ◽

Equilibrium Line Altitude ◽

Climatic Fluctuations ◽

The North ◽

Snow Line ◽

The Relationship ◽

Geologic Data

AbstractDuring 1974–75 glaciologic and geologic studies were conducted on a small (0.17 km2) avalanche-nourished glacier in the North Cascade Range of Washington. The approximate equilibrium-line altitude (ELA) for this ice body, informally called “Vesper” glacier, lies at 1475 m, some 300 m below the regional ELA value. Estimated annual accumulation was 6 100±675 mm during the two years of study; 15 to 30% of this flux resulted from avalanche and wind–transported snow. Average annual ablation during the period was 5 350 mm, giving a total net balance of + 1 600 mm for the two-year study period. “Vesper” glacier persists well below the regional snow-line because of excessive local precipitation, substantial avalanche contributions, and a favourable north-facing aspect.Neoglacial moraines indicate that maximum ELA lowering in this period was approximately 165 m and occurred prior to a.d. 1670. Minor re-advances occurred during the nineteenth century. These reconnaissance measurements are consistent with the sparse geologic data reported from other glaciers in the Cascade Range. While the relationship between regional lowering of snow-line and avalanche activity is uncertain at present, these data suggest that avalanche-nourished glaciers provide a useful record of climatic fluctuations.

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A Re-Assessment of the Mass Balance of the Lambert Glacier Drainage Basin, Antarctica

Journal of Glaciology ◽

10.3189/s0022143000004962 ◽

1985 ◽

Vol 31 (107) ◽

pp. 34-38 ◽

Cited By ~ 1

Author(s):

N. F. McIntyre

Keyword(s):

Mass Balance ◽

Drainage Basin ◽

Landsat Imagery ◽

Accumulation Rates ◽

Positive Mass ◽

Recent Calculation ◽

Ice Surface ◽

Low Mass ◽

Definition Of ◽

Lambert Glacier

AbstractRe-definition of the interior drainage basin Lambert Glacier, using the most recent sources of ice-surface elevations, has shown its area to be 902000 km2, that is, 17% less than previous estimates. Landsat imagery of the steepest sloping part of the basin shows there is bare ice over an area of 56000 km2. Other evidence also indicates exceptionally low mass inputs and the distribution of accumulation rates has been up-dated. The result is a positive mass balance for the interior basin (+2 Gt a–1 ) and error limits which fall below zero. This is 47% less than the most recent calculation and illustrates the difficulty in deriving mass budgets in regions where data are scarce.

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Mass Balance of Two High Arctic Plateau Ice Caps

Journal of Glaciology ◽

10.1017/s0022143000005438 ◽

1987 ◽

Vol 33 (113) ◽

pp. 123-128 ◽

Cited By ~ 15

Author(s):

Raymond S. Bradley ◽

Mark C. Serreze

Keyword(s):

Mass Balance ◽

High Arctic ◽

Climatic Conditions ◽

Ellesmere Island ◽

Equilibrium Line ◽

Ice Caps ◽

Mass Losses ◽

North Eastern ◽

Contemporary Climate ◽

Significant Mass

AbstractMass-balance measurements have been renewed on two small ice caps on north-eastern Ellesmere Island. Original stake networks were established in 1972 and 1976. Since then, both ice caps have experienced significant mass losses averaging –70 to –140 kg m−2a−1. They have also decreased in area. The equilibrium line in this area has averaged around 1150 m for the last decade or so. The ice caps are remnants of former climatic conditions and are out of equilibrium with contemporary climate.

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Modelled glacier equilibrium line altitudes during the mid-Holocene in the southern mid-latitudes

Climate of the Past Discussions ◽

10.5194/cpd-11-603-2015 ◽

2015 ◽

Vol 11 (2) ◽

pp. 603-636 ◽

Cited By ~ 1

Author(s):

C. Bravo ◽

M. Rojas ◽

B. M. Anderson ◽

A. N. Mackintosh ◽

E. Sagredo ◽

...

Keyword(s):

New Zealand ◽

Mass Balance ◽

Southern Hemisphere ◽

Equilibrium Line ◽

Balance Model ◽

Glacier Mass Balance ◽

Equilibrium Line Altitude ◽

Climate Conditions ◽

Precipitation Changes ◽

Autumn And Winter

Abstract. Glacier behaviour during the mid-Holocene (MH, 6000 year BP) in the Southern Hemisphere provides observational data to constrain our understanding of the origin and propagation of palaeo-climatic signals. We examine the climatic forcing of glacier expansion in the MH by evaluating modelled glacier equilibrium line altitude (ELA) and climate conditions during the MH compared with pre-industrial time (PI, year 1750) in the mid latitudes of the Southern Hemisphere, specifically in Patagonia and the South Island of New Zealand. Climate conditions for the MH are obtained from PMIP2 models simulations, which in turn force a simple glacier mass balance model to simulate changes in equilibrium-line altitude during this period. Climate conditions during the MH show significantly (p ≤ 0.05) colder temperatures in summer, autumn and winter, and significantly (p ≤ 0.05) warmer temperatures in spring. These changes are a consequence of insolation differences between the two periods. Precipitation does not show significant changes, but exhibits a temporal pattern with less precipitation from August to September and more precipitation from October to April during the MH. In response to these climatic changes, glaciers in both analysed regions have an ELA that is 15–33 m lower than PI during the MH. The main causes of this difference are the colder temperature during the MH, reinforcing previous results that mid-latitude glaciers are more sensitive to temperature change compared to precipitation changes. Differences in temperature have a dual effect on mass balance. First, during summer and early autumn less energy is available for melting. Second in late autumn and winter, lower temperatures cause more precipitation to fall as snow rather than rain, resulting in more accumulation and higher surface albedo. For these reasons, we postulate that the modelled ELA changes, although small, may help to explain larger glacier extents observed in the mid Holocene in both South America and New Zealand.

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Mass balance of Himalayan glaciers using AAR and ELA methods

Journal of Glaciology ◽

10.3189/s0022143000009631 ◽

1992 ◽

Vol 38 (128) ◽

pp. 101-104 ◽

Cited By ~ 12

Author(s):

Anil V. Kulkarni

Keyword(s):

Mass Balance ◽

Correlation Coefficients ◽

Western Himalaya ◽

Positive Mass ◽

Landsat Images ◽

Equilibrium Line Altitude ◽

Zero Mass ◽

Himalayan Glaciers ◽

Landsat Satellite ◽

Accumulation Area Ratio

AbstractThe accumulation area ratio (AAR) for Himalayan glaciers representing zero mass balance is substantially lower than for North America and Europe. Regression analysis suggests 0.44 for the AAR representing zero mass balance in the western Himalaya. A good correlation was observed when this method was applied to individual glaciers such as Gara and Gor-Garang in Himachal Pradesh, India. The correlation coefficients (r), using 6 and 7 years of data, respectively, were 0.88 and 0.96 for Gara and Gor-Garang Glaciers, respectively. However, when data from six western Himalayan glaciers were correlated, the correlation was 0.74. The AAR was also estimated by using Landsat images which can be useful in obtaining a trend in mass balance for a large number of Himalayan glaciers for which very little information exists.A higher correlation was observed between equilibrium-line altitude (ELA) and mass balance. The field data from Gara and Gor-Garang Glaciers shows a high correlation coefficient, i.e. −0.92 and −0.94, respectively. The ELA values obtained from the Landsat satellite images combined with topographic maps suggest positive mass balance for the year 1986–87 and negative for 1987–88.

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Can the Mass Balance of a Glacier be Estimated from its Equilibrium-Line Altitude?

Journal of Glaciology ◽

10.3189/s0022143000006237 ◽

1984 ◽

Vol 30 (106) ◽

pp. 364-368 ◽

Cited By ~ 6

Author(s):

Roger J. Braithwaite

Keyword(s):

Mass Balance ◽

Linear Relationship ◽

Sufficient Accuracy ◽

Statistical Analyses ◽

Equilibrium Line ◽

Model Parameters ◽

Equilibrium Line Altitude ◽

Direct Measurements ◽

Balanced Budget ◽

Two Parameters

AbstractThe possibility of replacing or supplementing direct measurements of mass balance by estimates calculated from equilibrium-line altitude (ELA) measurements is investigated by statistical analyses of data from 31 glaciers. A linear relationship between mass balance and ELA in terms of two parameters, the effective balance gradient and the balanced-budget ELA, is tested. It is concluded that existing mass-balance series can be usefully extrapolated by using ELA data for additional years. However, accurate mass balance cannot be calculated for glaciers where no such measurements have been made because of the difficulties in prescribing the two model parameters with sufficient accuracy. For example, the effective balance gradient is of the order of 5 mm water/m so that errors of only a few decametres in the estimation of the balanced-budget ELA can have a great effect upon calculations of mass balance.

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Mass Balance of “Vesper” Glacier, Washington, U.S.A.

Journal of Glaciology ◽

10.3189/s0022143000015380 ◽

1981 ◽

Vol 27 (96) ◽

pp. 271-282

Author(s):

David P. Dethier ◽

Jan E. Frederick

Keyword(s):

Nineteenth Century ◽

Mass Balance ◽

Cascade Range ◽

Equilibrium Line ◽

Equilibrium Line Altitude ◽

Climatic Fluctuations ◽

The North ◽

Snow Line ◽

The Relationship ◽

Geologic Data

AbstractDuring 1974–75 glaciologic and geologic studies were conducted on a small (0.17 km2) avalanche-nourished glacier in the North Cascade Range of Washington. The approximate equilibrium-line altitude (ELA) for this ice body, informally called “Vesper” glacier, lies at 1475 m, some 300 m below the regional ELA value. Estimated annual accumulation was 6 100±675 mm during the two years of study; 15 to 30% of this flux resulted from avalanche and wind–transported snow. Average annual ablation during the period was 5 350 mm, giving a total net balance of + 1 600 mm for the two-year study period. “Vesper” glacier persists well below the regional snow-line because of excessive local precipitation, substantial avalanche contributions, and a favourable north-facing aspect.Neoglacial moraines indicate that maximum ELA lowering in this period was approximately 165 m and occurred prior to a.d. 1670. Minor re-advances occurred during the nineteenth century. These reconnaissance measurements are consistent with the sparse geologic data reported from other glaciers in the Cascade Range. While the relationship between regional lowering of snow-line and avalanche activity is uncertain at present, these data suggest that avalanche-nourished glaciers provide a useful record of climatic fluctuations.

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