scholarly journals The transfer of mass-balance profiles to unmeasured glaciers

2009 ◽  
Vol 50 (50) ◽  
pp. 185-190 ◽  
Author(s):  
Michael Kuhn ◽  
Jakob Abermann ◽  
Michael Bacher ◽  
Marc Olefs
Keyword(s):  
Mass Balance ◽  
Digital Elevation Models ◽  
Quantitative Information ◽  
Equilibrium Line ◽  
Equilibrium Line Altitude ◽  
Altitude Exposure ◽  
Digital Elevation ◽  
Area Distribution ◽  
Elevation Changes ◽  
The Mean

AbstractFor estimation of the mass balance of an unmeasured glacier, its area distribution with altitude, s (h), generally is the only available quantitative information. The appropriate specific balance profile, b (h), needs to be transferred from a measured glacier, where transfer means modification and adaptation to the topographic and climatic situation of the unmeasured glacier, such as altitude, exposure to sun and wind, or temperature. This study proposes the area median elevation, M, as a parameter of prime importance for the transfer. Using as an example ten Alpine glaciers, the similarity of M and equilibrium-line altitude is quantified and the effect of aspect and surrounding topography is qualitatively suggested. The transfer of b (h) between well-measured glaciers yielded differences in the mean specific balance of 150 mm in the mean of a 10 year period, which corresponds to a change in median altitude by 30 m. Transfer of b (h) with a shift according to median glacier elevation to a basin with 27 glaciers and 23 km2 ice cover agreed to within 10% with elevation changes converted from digital elevation models of 1969 and 1997.

scholarly journals Quality Assessment and Glaciological Applications of Digital Elevation Models Derived from Space-Borne and Aerial Images over Two Tidewater Glaciers of Southern Spitsbergen

2019 ◽  
Vol 11 (9) ◽  
pp. 1121 ◽  
Author(s):  
Małgorzata Błaszczyk ◽  
Dariusz Ignatiuk ◽  
Mariusz Grabiec ◽  
Leszek Kolondra ◽  
Michał Laska ◽  
...  
Keyword(s):  
Mass Balance ◽  
Digital Elevation Models ◽  
Control Point ◽  
Aerial Photographs ◽  
Differential Gps ◽  
Tidewater Glaciers ◽  
Digital Elevation ◽  
High Resolution Satellite Images ◽  
Elevation Changes ◽  
Geodetic Mass Balance

In this study, we assess the accuracy and precision of digital elevation models (DEM) retrieved from aerial photographs taken in 2011 and from Very High Resolution satellite images (WorldView-2 and Pléiades) from the period 2012–2017. Additionally, the accuracy of the freely available Strip product of ArcticDEM was verified. We use the DEMs to characterize geometry changes over Hansbreen and Hornbreen, two tidewater glaciers in southern Spitsbergen, Svalbard. The satellite-based DEMs from WorldView-2 and Pléiades stereo pairs were processed using the Rational Function Model (RFM) without and with one ground control point. The elevation quality of the DEMs over glacierized areas was validated with in situ data: static differential GPS survey of mass balance stakes and GPS kinematic data acquired during ground penetrating radar survey. Results demonstrate the usefulness of the analyzed sources of DEMs for estimation of the total geodetic mass balance of the Svalbard glaciers. DEM accuracy is sufficient to investigate glacier surface elevation changes above 1 m. Strips from the ArcticDEM are generally precise, but some of them showed gross errors and need to be handled with caution. The surface of Hansbreen and Hornbreen has been lowering in recent years. The average annual elevation changes for Hansbreen were more negative in the period 2015–2017 (−2.4 m a−1) than in the period 2011–2015 (−1.7 m a−1). The average annual elevation changes over the studied area of Hornbreen for the period 2012–2017 amounted to −1.6 m a−1. The geodetic mass balance for Hansbreen was more negative than the climatic mass balance estimated using the mass budget method, probably due to underestimation of the ice discharge. From 2011 to 2017, Hansbreen lost on average over 1% of its volume each year. Such a high rate of relative loss illustrates how fast these glaciers are responding to climate change.

scholarly journals Changes in ice volume of the Ningchan No.1 Glacier, China, from 1972 to 2014, as derived from in situ measurements

2017 ◽  
Vol 63 (242) ◽  
pp. 1025-1033 ◽  
Author(s):  
BO CAO ◽  
BAOTIAN PAN ◽  
WEIJIN GUAN ◽  
JIE WANG ◽  
ZHENLING WEN
Keyword(s):  
Mass Balance ◽  
Global Climate ◽  
Equilibrium Line Altitude ◽  
Mountain Ranges ◽  
Ice Volume ◽  
Digital Elevation ◽  
Maximum Elevation ◽  
The Mean ◽  
Ground Penetrating

ABSTRACTGlobal climate change is causing widespread glacier retreat, with many small glaciers disappearing from the world's mountain ranges. We obtained the annual mass balance of a small glacier (the Ningchan No.1 Glacier) located on the northeastern Tibetan Plateau, from the years 2010 to 2015 using glaciological and geodetic methods. We also measured the glacier's thickness in 2014 using ground-penetrating radar. Employing topographical maps and ZY-3 images, we obtained Digital Elevation Models for 1972 and 2014. Our results showed that the mean annual mass balance from 2010 to 2015 was ~−0.9 ± 0.5 m w.e. The mean equilibrium line altitude was ~4680 m in the period 2010–15, which exceeds the maximum elevation of the glacier. The glacier has lost area and mass across its elevation range. The mean ice thickness was 24.0 ± 2.5 m in 2014. From 1972 to 2014, the glacier's area shrank from 0.77 ± 0.05 to 0.39 ± 0.04 km2, and the ice volume decreased by (14.96 ± 0.97) × 106 m3, equivalent to (12.72 ± 0.82) × 106 t w.e. over the same period.

scholarly journals Strong ELA increase causes fast mass loss of glaciers in central Spitsbergen

2015 ◽  
Vol 9 (6) ◽  
pp. 6153-6185
Author(s):  
J. Małecki
Keyword(s):  
Mass Balance ◽  
Ice Age ◽  
The Arctic ◽  
Glacier Area ◽  
Equilibrium Line Altitude ◽  
Digital Elevation ◽  
Glacier Changes ◽  
Central Regions ◽  
The Mean ◽  
Geodetic Mass Balance

Abstract. Svalbard is a heavily glacier covered archipelago in the Arctic. Its central regions, including Dickson Land (DL), are occupied by small alpine glaciers, which post-Little Ice Age (LIA) changes remain only sporadically investigated. This study presents a comprehensive analysis of glacier changes in DL based on inventories compiled from topographic maps and digital elevation models (DEMs) for LIA, 1960's, 1990 and 2009/11. The 37.9 ± 12.1 % glacier area decrease in DL (i.e. from 334.1 ± 38.4 km2 during LIA to 207.4 ± 4.6 km2 in 2009/11) has been primarily caused by accelerating termini retreat. The mean 1990–2009/11 geodetic mass balance of glaciers was -0.70 ± 0.06 m a-1 (-0.63 ± 0.05 m w.e. a-1), being one of the most negative from Svalbard regional means known from the literature. If the same figure was to be applied for other similar regions of central Spitsbergen, that would result in a considerable contribution to total Svalbard mass balance despite negligible proportion to total glacier area. Glacier changes in Dickson Land were linked to dramatic equilibrium line altitude (ELA) shift, which in the period 1990–2009/11 has been located ca. 500 m higher than required for steady-state. The mass balance of central Spitsbergen glaciers seems to be therefore more sensitive to climate change than previously thought.

scholarly journals Glacier elevation and mass changes over the central Karakoram region estimated from TanDEM-X and SRTM/X-SAR digital elevation models

2016 ◽  
Vol 57 (71) ◽  
pp. 273-281 ◽  
Author(s):  
Melanie Rankl ◽  
Matthias Braun
Keyword(s):  
High Resolution ◽  
Snow Cover ◽  
Digital Elevation Models ◽  
Mass Balances ◽  
Freshwater Resources ◽  
Digital Elevation ◽  
Glacier Changes ◽  
Kinematic Waves ◽  
Elevation Changes ◽  
River Communities

AbstractSnow cover and glaciers in the Karakoram region are important freshwater resources for many down-river communities as they provide water for irrigation and hydropower. A better understanding of current glacier changes is hence an important informational baseline. We present glacier elevation changes in the central Karakoram region using TanDEM-X and SRTM/X-SAR DEM differences between 2000 and 2012. We calculated elevation differences for glaciers with advancing and stable termini or surge-type glaciers separately using an inventory from a previous study. Glaciers with stable and advancing termini since the 1970s showed nearly balanced elevation changes of -0.09 ±0.12 m a-1 on average or mass budgets of -0.01 ±0.02Gt a-1 (using a density of 850 kg m-3). Our findings are in accordance with previous studies indicating stable or only slightly negative glacier mass balances during recent years in the Karakoram. The high-resolution elevation changes revealed distinct patterns of mass relocation at glacier surfaces during active surge cycles. The formation of kinematic waves at quiescent surge-type glaciers could be observed and points towards future active surge behaviour. Our study reveals the potential of the TanDEM-X mission to estimate geodetic glacier mass balances, but also points to still existing uncertainties induced by the geodetic method.

scholarly journals Map-based methods for estimating glacier equilibrium-line altitudes

2003 ◽  
Vol 49 (166) ◽  
pp. 329-336 ◽  
Author(s):  
Katherine C. Leonard ◽  
Andrew G. Fountain
Keyword(s):  
Mass Balance ◽  
Sea Level ◽  
Equilibrium Line ◽  
Topographic Maps ◽  
Kinematic Waves ◽  
The Mean

AbstractWe examine the validity of two methods for estimating glacier equilibrium-line altitudes (ELAs) from topographic maps. The ELA determined by contour inflection (the kinematic ELA) and the mean elevation of the glacier correlate extremely well with the ELA determined from mass-balance data (observed ELA). However, the range in glacier elevations above sea level is much larger than the variation in ELA, making this correlation unhelpful. The data were normalized and a reasonable correlation (r2 = 0.59) was found between observed and kinematic ELA.The average of the normalized kinematic ELAs was consistently located down-glacier from the observed ELA, consistent with theory. The normalized mean elevation of the glacier exhibited no correlation and suggests that the toe–headwall altitude ratio is not a good approximation for the ELA. Kinematic waves had no effect on the position of the kinematic ELA. Therefore, topographic maps of glacier surfaces can be used to infer the position of the ELA and provide a method for estimating past ELAs from historic topographic maps.

scholarly journals Seasonal and annual mass balances of Mera and Pokalde glaciers (Nepal Himalaya) since 2007

2013 ◽  
Vol 7 (4) ◽  
pp. 3337-3378 ◽  
Author(s):  
P. Wagnon ◽  
C. Vincent ◽  
Y. Arnaud ◽  
E. Berthier ◽  
E. Vuillermoz ◽  
...  
Keyword(s):  
Mass Balance ◽  
Cross Sections ◽  
Mass Balances ◽  
Equilibrium Line Altitude ◽  
Nepal Himalaya ◽  
Limited Mass ◽  
In Situ Observations ◽  
The Mean ◽  
Southern Flank

Abstract. In the Everest region, Nepal, ground-based monitoring programs were started on the debris-free Mera Glacier (27.7° N, 86.9° E; 5.1 km2, 6420 to 4940 m a.s.l.) in 2007 and on the small Pokalde Glacier (27.9° N, 86.8° E; 0.1 km2, 5690 to 5430 m a.s.l., ∼ 25 km North of Mera Glacier) in 2009. These glaciers lie on the southern flank of the central Himalaya under the direct influence of the Indian monsoon and receive more than 80% of their annual precipitation in summer (June to September). Despite a large inter-annual variability with glacier-wide mass balances ranging from −0.77± 0.40 m w.e. in 2011–2012 (Equilibrium-line altitude (ELA) at ∼ 6055 m a.s.l.) to + 0.46 ± 0.40 m w.e. in 2010–2011 (ELA at ∼ 5340 m a.s.l.), Mera Glacier has been shrinking at a moderate mass balance rate of −0.10± 0.40 m w.e. yr−1 since 2007. Ice fluxes measured at two distinct transverse cross sections at ∼ 5350 m a.s.l. and ∼ 5520 m a.s.l. confirm that the mean state of this glacier over the last one or two decades corresponds to a limited mass loss, in agreement with remotely-sensed region-wide mass balances of the Everest area. Seasonal mass balance measurements show that ablation and accumulation are concomitant in summer which in turn is the key season controlling the annual glacier-wide mass balance. Unexpectedly, ablation occurs at all elevations in winter due to wind erosion and sublimation, with remobilized snow likely being sublimated in the atmosphere. Between 2009 and 2012, the small Pokalde Glacier lost mass more rapidly than Mera Glacier with respective mean glacier-wide mass balances of −0.72 and −0.26 ± 0.40 m w.e. yr−1. Low-elevation glaciers, such as Pokalde Glacier, have been usually preferred for in-situ observations in Nepal and more generally in the Himalayas, which may explain why compilations of ground-based mass balances are biased toward negative values compared with the regional mean under the present-day climate.

scholarly journals Glacier equilibrium line altitude variations during the “Little Ice Age” in the Mediterranean Andes (30◦–37◦ S)

2019 ◽  
Author(s):  
Álvaro González-Reyes ◽  
Claudio Bravo ◽  
Mathias Vuille ◽  
Martin Jacques-Coper ◽  
Maisa Rojas ◽  
...  
Keyword(s):  
Little Ice Age ◽  
Pearson Correlation ◽  
Temporal Changes ◽  
Global Climate Models ◽  
Ice Age ◽  
Equilibrium Line ◽  
Equilibrium Line Altitude ◽  
Mountainous Regions ◽  
The Mean ◽  
The Mediterranean

Abstract. The "Little Ice Age" (LIA; 1500–1850 Common Era (CE)), has long been recognized as the last period when mountain glaciers in many regions of the Northern Hemisphere (NH) recorded extensive growth intervals in terms of their ice mass and frontal position. The knowledge about this relevant paleoclimatic interval is vast in mountainous regions such as the Alps and Rocky Mountains in North America. However, in extra-tropical Andean sub-regions such as the Mediterranean Andes of Chile and Argentina (MA; 30º–37º S), the LIA has been poorly documented. Paradoxically, the few climate reconstructions performed in the MA based on lake sediments and tree rings do not show clear evidence of a LIA climate anomaly as observed in the NH. In addition, recent studies have demonstrated temporal differences between mean air temperature variations across the last millennium between both hemispheres. This motivates our hypothesis that the LIA period was not associated with a significant climate perturbation in the MA region. Considering this background, we performed an experiment using daily climatic variables from three Global Climate Models (GCMs) to force a novel glaciological model. In this way, we simulated temporal variations of the glacier equilibrium-line altitude (ELA) to evaluate the glacier response during the period 1500–1848 CE. Overall, each GCM shows temporal changes in annual ELA, with anomalously low elevations during 1640–1670 and 1800–1848 CE. An interval with high ELA values was identified during 1550–1575 CE. The spectral properties of the mean annual ELA in each GCM present significant periodicities between 2–7 years, and also significant decadal to multi-decadal signals. In addition, significant and coherent cycles at interannual to multi-decadal scales were detected between modeled mean annual ELAs and the first EOF1 extracted from Sea Surface Temperature (SST) within the El Niño 3.4 of each GCM. Finally, significant Pearson correlation coefficients were obtained between the mean annual ELA and Pacific SST on interannual to multi-decadal timescales. According to our findings, we propose that Pacific SST variability was the main modulator of temporal changes of the ELA in the MA region of South America during 1500–1848 CE.

scholarly journals Twenty-one years of mass balance observations along the K-transect, West Greenland

2012 ◽  
Vol 4 (1) ◽  
pp. 31-35 ◽  
Author(s):  
R. S. W. van de Wal ◽  
W. Boot ◽  
C. J. P. P. Smeets ◽  
H. Snellen ◽  
M. R. van den Broeke ◽  
...  
Keyword(s):  
Mass Balance ◽  
Entire Period ◽  
Surface Mass Balance ◽  
Altitude Range ◽  
Equilibrium Line Altitude ◽  
Surface Mass ◽  
West Greenland ◽  
Increasing Trend ◽  
Period Data ◽  
The Mean

Abstract. A 21-yr record is presented of surface mass balance measurements along the K-transect. The series covers the period 1990–2011. Data are available at eight sites along a transect over an altitude range of 380–1850 m at approximately 67° N in West Greenland. The surface mass balance gradient is on average 3.8 × 10−3 m w.e. m−1, and the mean equilibrium line altitude is 1553 m a.s.l. Only the lower three sites within 10 km of the margin up to an elevation of 700 m experience a significant increasing trend in the ablation over the entire period. Data are available at: doi:10.1594/PANGAEA.779181.

scholarly journals Mass-balance estimates on the glacier complex Kongsvegen and Sveabreen, Spitsbergen, Svalbard, using radioactive layers

1994 ◽  
Vol 40 (135) ◽  
pp. 368-376 ◽  
Author(s):  
Bernard Lefauconnier ◽  
Jon Ove Hagen ◽  
Jean Francis Pinglot ◽  
Michel Pourchet
Keyword(s):  
Mass Balance ◽  
Chernobyl Accident ◽  
Ice Cores ◽  
Equilibrium Line ◽  
Novaya Zemlya ◽  
Topographic Data ◽  
Positive Balance ◽  
The Mean ◽  
Nuclear Tests

AbstractAnalyses of total β and γ radioactivity have been carried out on ten shallow ice cores collected in 1989 and 1990 on Kongsvegen and Sveabreen, Spitsbergen. No peak of total β radioactivity, corresponding to the Chernobyl accident (1986), can be identified. Chernobyl layers were identified by 137Cs and 134Cs activities, and a signal from the nuclear tests in Novaya Zemlya (1961–62), was detected at one location by 137Cs activity. The mean net accumulation for the periods 1986–89 and 1962–88 was estimated for both glaciers. Using topographic data, the mean net ablation on Kongsvegen was estimated for the period 1964–90 and the mean net balances were calculated. The results agree with recent direct glaciological balance measurements. For the period 1986–89, the net accumulation was higher on Sveabreen than on Kongsvegen, and the equilibrium-line altitudes (ELA) were around 450 and 520 m a.s.l., respectively. Kongsvegen had a positive balance of 0.11 m w.eq. and Sveabreen was in equilibrium, whereas for the last 26 years the balance of Kongsvegen was slightly negative (−0.10 m w.eq.) and the ELA was around 560 m a.s.l.

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

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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