Geodetic mass balance of Abramov Glacier from 1975 to 2015

Abstract Multi-decadal mass loss estimates are available for few glaciers of Central Asia. On Abramov Glacier (Pamir-Alay, Kyrgyzstan), comprehensive long-term glaciological measurements have been carried out from 1968 to 1999 and re-initiated in 2011. A climatological interpretation of this benchmark glacier in Central Asia requires bridging the gap between historical and renewed measurements. This is achieved here by computing the geodetic mass balance from 1975 to 2015 using previously unreleased Soviet aerial imagery and Pléaides stereo-imagery. During 1975–2015, Abramov Glacier lost 2.2 km2 (8.2%) of its area. The mean annual thickness change was − 0.43 ± 0.14 m a−1 for the period 1975–2015, corresponding to a volume change of − 0.45 ± 0.15 km3. The average specific geodetic mass balance amounts to − 0.38 ± 0.12 m w.e. a−1. The 1975–2015 glacier mass loss lies within the range of glaciological and geodetic mass-balance estimates that were previously published for disparate and shorter time intervals since 1968. This study covers a much longer time period than earlier geodetic estimates and demonstrates the capacity to geodetically constrain glacier change at high spatial resolution in Central Asia using historic aerial imagery and Structure from Motion techniques. Therefore, it could serve as a benchmark for future studies of regional mass change.

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Geodetic Mass Balance of Haxilegen Glacier No. 51, Eastern Tien Shan, from 1964 to 2018

Remote Sensing ◽

10.3390/rs14020272 ◽

2022 ◽

Vol 14 (2) ◽

pp. 272

Author(s):

Chunhai Xu ◽

Zhongqin Li ◽

Feiteng Wang ◽

Jianxin Mu ◽

Xin Zhang

Keyword(s):

Mass Loss ◽

Mass Balance ◽

Laser Scanning ◽

Mean Value ◽

Tien Shan ◽

Glacier Mass Balance ◽

Topographic Map ◽

Glacier Surface ◽

Elevation Changes ◽

Geodetic Mass Balance

The eastern Tien Shan hosts substantial mid-latitude glaciers, but in situ glacier mass balance records are extremely sparse. Haxilegen Glacier No. 51 (eastern Tien Shan, China) is one of the very few well-measured glaciers, and comprehensive glaciological measurements were implemented from 1999 to 2011 and re-established in 2017. Mass balance of Haxilegen Glacier No. 51 (1999–2015) has recently been reported, but the mass balance record has not extended to the period before 1999. Here, we used a 1:50,000-scale topographic map and long-range terrestrial laser scanning (TLS) data to calculate the area, volume, and mass changes for Haxilegen Glacier No. 51 from 1964 to 2018. Haxilegen Glacier No. 51 lost 0.34 km2 (at a rate of 0.006 km2 a−1 or 0.42% a−1) of its area during the period 1964–2018. The glacier experienced clearly negative surface elevation changes and geodetic mass balance. Thinning occurred almost across the entire glacier surface, with a mean value of −0.43 ± 0.12 m a−1. The calculated average geodetic mass balance was −0.36 ± 0.12 m w.e. a−1. Without considering the error bounds of mass balance estimates, glacier mass loss over the past 50 years was in line with the observed and modeled mass balance (−0.37 ± 0.22 m w.e. a−1) that was published for short time intervals since 1999 but was slightly less negative than glacier mass loss in the entire eastern Tien Shan. Our results indicate that Riegl VZ®-6000 TLS can be widely used for mass balance measurements of unmonitored individual glaciers.

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Longest time series of glacier mass changes in the Himalaya based on stereo imagery

The Cryosphere Discussions ◽

10.5194/tcd-4-2593-2010 ◽

2010 ◽

Vol 4 (4) ◽

pp. 2593-2613 ◽

Cited By ~ 3

Author(s):

T. Bolch ◽

T. Pieczonka ◽

D. I. Benn

Keyword(s):

Time Series ◽

Mass Loss ◽

Mass Balance ◽

Aerial Images ◽

Glacier Mass Balance ◽

Glacier Changes ◽

Debris Cover ◽

Stereo Imagery ◽

Glacier Velocity ◽

The Himalaya

Abstract. Mass loss of Himalayan glaciers has wide-ranging consequences such as declining water resources, sea level rise and an increasing risk of glacial lake outburst floods (GLOFs). The assessment of the regional and global impact of glacier changes in the Himalaya is, however, hampered by a lack of mass balance data for most of the range. Multi-temporal digital terrain models (DTMs) allow glacier mass balance to be calculated since the availability of stereo imagery. Here we present the longest time series of mass changes in the Himalaya and show the high value of early stereo spy imagery such as Corona (years 1962 and 1970) aerial images and recent high resolution satellite data (Cartosat-1) to calculate a time series of glacier changes south of Mt. Everest, Nepal. We reveal that the glaciers are significantly losing mass with an increasing rate since at least ~1970, despite thick debris cover. The specific mass loss is 0.32 ± 0.08 m w.e. a−1, however, not higher than the global average. The spatial patterns of surface lowering can be explained by variations in debris-cover thickness, glacier velocity, and ice melt due to exposed ice cliffs and ponds.

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Terminus advance, kinematics and mass redistribution during eight surges of Donjek Glacier, St. Elias Range, Canada, 1935 to 2016

Journal of Glaciology ◽

10.1017/jog.2019.34 ◽

2019 ◽

Vol 65 (252) ◽

pp. 565-579 ◽

Cited By ~ 4

Author(s):

WILLIAM KOCHTITZKY ◽

HESTER JISKOOT ◽

LUKE COPLAND ◽

ELLYN ENDERLIN ◽

ROBERT MCNABB ◽

...

Keyword(s):

Mass Balance ◽

Dynamic Balance ◽

Active Phase ◽

Aerial Photographs ◽

Ablation Zone ◽

Elevation Change ◽

Glacier Terminus ◽

Mass Redistribution ◽

Geodetic Mass Balance

ABSTRACTDonjek Glacier has an unusually short and regular surge cycle, with eight surges identified since 1935 from aerial photographs and satellite imagery with a ~12 year repeat interval and ~2 year active phase. Recent surges occurred during a period of long-term negative mass balance and cumulative terminus retreat of 2.5 km since 1874. In contrast to previous work, we find that the constriction where the valley narrows and bedrock lithology changes, 21 km from the terminus, represents the upper limit of surging, with negligible surface speed or elevation change up-glacier from this location. This positions the entire surge-type portion of the glacier in the ablation zone. The constriction geometry does not act as the dynamic balance line, which we consistently find at 8 km from the glacier terminus. During the 2012–2014 surge event, the average lowering rate in the lowest 21 km of the glacier was 9.6 m a−1, while during quiescence it was 1.0 m a−1. Due to reservoir zone refilling, the ablation zone has a positive geodetic balance in years immediately following a surge event. An active surge phase can result in a strongly negative geodetic mass balance over the surge-type portion of the glacier.

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Multi-decadal mass loss of glaciers in the Everest area (Nepal Himalaya) derived from stereo imagery

The Cryosphere ◽

10.5194/tc-5-349-2011 ◽

2011 ◽

Vol 5 (2) ◽

pp. 349-358 ◽

Cited By ~ 248

Author(s):

T. Bolch ◽

T. Pieczonka ◽

D. I. Benn

Keyword(s):

Time Series ◽

Mass Loss ◽

Mass Balance ◽

Aerial Images ◽

Glacier Mass Balance ◽

Ice Melt ◽

Debris Cover ◽

Stereo Imagery ◽

Glacier Velocity ◽

The Himalaya

Abstract. Mass loss of Himalayan glaciers has wide-ranging consequences such as changing runoff distribution, sea level rise and an increasing risk of glacial lake outburst floods (GLOFs). The assessment of the regional and global impact of glacier changes in the Himalaya is, however, hampered by a lack of mass balance data for most of the range. Multi-temporal digital terrain models (DTMs) allow glacier mass balance to be calculated. Here, we present a time series of mass changes for ten glaciers covering an area of about 50 km2 south and west of Mt. Everest, Nepal, using stereo Corona spy imagery (years 1962 and 1970), aerial images and recent high resolution satellite data (Cartosat-1). This is the longest time series of mass changes in the Himalaya. We reveal that the glaciers have been significantly losing mass since at least 1970, despite thick debris cover. The specific mass loss for 1970–2007 is 0.32 ± 0.08 m w.e. a−1, however, not higher than the global average. Comparisons of the recent DTMs with earlier time periods indicate an accelerated mass loss. This is, however, hardly statistically significant due to high uncertainty, especially of the lower resolution ASTER DTM. The characteristics of surface lowering can be explained by spatial variations of glacier velocity, the thickness of the debris-cover, and ice melt due to exposed ice cliffs and ponds.

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Decay of a long-term monitored glacier: Careser Glacier (Ortles-Cevedale, European Alps)

The Cryosphere ◽

10.5194/tc-7-1819-2013 ◽

2013 ◽

Vol 7 (6) ◽

pp. 1819-1838 ◽

Cited By ~ 38

Author(s):

L. Carturan ◽

C. Baroni ◽

M. Becker ◽

A. Bellin ◽

O. Cainelli ◽

...

Keyword(s):

Mass Loss ◽

Mass Balance ◽

Mass Loss Rate ◽

Regional Scale ◽

European Alps ◽

Systematic Observation ◽

Average Mass ◽

Observation Series ◽

The 19Th Century

Abstract. The continuation of valuable, long-term glacier observation series is threatened by the accelerated mass loss which currently affects a large portion of so-called "benchmark" glaciers. In this work we present the evolution of the Careser Glacier, from the beginning of systematic observation at the end of the 19th century to its current condition in 2012. In addition to having one of the longest and richest observation records among the Italian glaciers, Careser is unique in the Italian Alps for its 46 yr mass balance series that started in 1967. In the present study, variations in the length, area and volume of the glacier since 1897 are examined, updating and validating the series of direct mass balance observations and adding to the mass balance record into the past using the geodetic method. The glacier is currently strongly out of balance and in rapid decay; its average mass loss rate over the last 3 decades was 1.5 m water equivalent per year, increasing to 2.0 m water equivalent per year in the last decade. Although these rates are not representative at a regional scale, year-to-year variations in mass balance show an unexpected increase in correlation with other glaciers in the Alps, during the last 3 decades. If mass loss continues at this pace, the glacier will disappear within a few decades, putting an end to this unique observation series.

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Airborne surface profiling of glaciers: a case-study in Alaska

Journal of Glaciology ◽

10.3189/s002214300000352x ◽

1996 ◽

Vol 42 (142) ◽

pp. 538-547 ◽

Cited By ~ 9

Author(s):

Κ. A. Echelmeyer ◽

W. D. Harrison ◽

C. F. Larsen ◽

J. Sapiano ◽

Mitchell J. E. ◽

...

Keyword(s):

Time Intervals ◽

Glacier Surface ◽

Alaska Range ◽

Thickness Change ◽

Surface Profiling ◽

Bear Lake ◽

South Central ◽

Short Time

AbstractA relatively lightweight and simple airborne system for surface elevation profiling of glaciers in narrow mountain valleys has been developed and tested. The aircraft position is determined by kinematic global positioning system (GPS) methods. The distance to the glacier surface is determined with a laser ranger. The accuracy is about 0.3 m, sufficient to permit future changes to be observed over short time intervals. Long-term changes can be estimated by comparison of profiles with existing maps. Elevation profiles obtained in 1993–94 from three glaciers in central and south-central Alaska are compared with maps made about 1950. The resulting area-averaged, seasonally corrected thickness changes during the interval are: Gulkana Glacier (central Alaska Range)–11 m, Worthington Glacier (central Chugach Mountains) +7 m, and Bear Lake Glacier (Kenai Mountains) −12 m. All three glaciers retreated during the interval of comparison. The estimated uncertainty in the average thickness change is ±5 m. which is mainly due to errors in the existing maps. Constraints on the accuracy of the maps are obtained by profiling in proglacial areas.

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Glaciological and geodetic mass balance of ten long-term glaciers in Norway

The Cryosphere Discussions ◽

10.5194/tcd-9-6581-2015 ◽

2015 ◽

Vol 9 (6) ◽

pp. 6581-6626 ◽

Cited By ~ 2

Author(s):

L. M. Andreassen ◽

H. Elvehøy ◽

B. Kjøllmoen ◽

R. V. Engeset

Keyword(s):

Mass Balance ◽

Uncertainty Assessment ◽

Glacier Mass Balance ◽

Surface Mass ◽

Independent Observations ◽

Observation Series ◽

Field Notes ◽

Geodetic Mass Balance ◽

Year 2000

Abstract. The glaciological and geodetic methods provide independent observations of glacier mass balance. The glaciological method measures the surface mass balance, on a seasonal or annual basis, whereas the geodetic method measures surface, internal and basal mass balances, over a period of years or decades. In this paper, we reanalyse the 10 glaciers with long-term mass balance series in Norway. The reanalysis includes (i) homogenisation of both glaciological and geodetic observation series, (ii) uncertainty assessment, (iii) estimates of generic differences including estimates of internal and basal melt, (iv) validation, and (v) partly calibration of mass balance series. This study comprises an extensive set of data (454 mass balance years, 34 geodetic surveys and large volumes of supporting data, such as metadata and field notes). In total, 21 periods of data were compared and the results show discrepancies between the glaciological and geodetic methods for some glaciers, which in part are attributed to internal and basal ablation and in part to inhomogeneity in the data processing. Deviations were smaller than 0.2 m w.e. a−1 for 12 out of 21 periods. Calibration was applied to seven out of 21 periods, as the deviations were larger than the uncertainty. The reanalysed glaciological series shows a more consistent signal of glacier change over the period of observations than previously reported: six glaciers had a significant mass loss (14–22 m w.e.) and four glaciers were nearly in balance. All glaciers have lost mass after year 2000. More research is needed on the sources of uncertainty, to reduce uncertainties and adjust the observation programmes accordingly. The study confirms the value of carrying out independent high-quality geodetic surveys to check and correct field observations.

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Mass balances of Yala and Rikha Samba glaciers, Nepal, from 2000 to 2017

Earth System Science Data ◽

10.5194/essd-13-3791-2021 ◽

2021 ◽

Vol 13 (8) ◽

pp. 3791-3818

Author(s):

Dorothea Stumm ◽

Sharad Prasad Joshi ◽

Tika Ram Gurung ◽

Gunjan Silwal

Keyword(s):

Mass Loss ◽

Mass Balance ◽

Water Resource Management ◽

Important Variable ◽

Glacier Mass Balance ◽

Mass Balances ◽

Monitoring Strategies ◽

Length Changes ◽

The Mean ◽

Geodetic Mass Balance

Abstract. The glacier mass balance is an important variable to describe the climate system and is used for various applications like water resource management or runoff modelling. The direct or glaciological method and the geodetic method are the standard methods to quantify glacier mass changes, and both methods are an integral part of international glacier monitoring strategies. In 2011, we established two glacier mass-balance programmes on Yala and Rikha Samba glaciers in the Nepal Himalaya. Here we present the methods and data of the directly measured annual mass balances for the first six mass-balance years for both glaciers from 2011/2012 to 2016/2017. For Yala Glacier we additionally present the directly measured seasonal mass balance from 2011 to 2017, as well as the mass balance from 2000 to 2012 obtained with the geodetic method. In addition, we analysed glacier length changes for both glaciers. The directly measured average annual mass-balance rates of Yala and Rikha Samba glaciers are −0.80 ± 0.28 and −0.39 ± 0.32 m w.e. a−1, respectively, from 2011 to 2017. The geodetically measured annual mass-balance rate of Yala Glacier based on digital elevation models from 2000 and 2012 is −0.74 ± 0.53 m w.e. The cumulative mass loss for the period 2011 to 2017 for Yala and Rikha Samba glaciers is −4.80 ± 0.69 and −2.34 ± 0.79 m w.e., respectively. The mass loss on Yala Glacier from 2000 to 2012 is −8.92 ± 6.33 m w.e. The winter balance of Yala Glacier is positive, and the summer balance is negative in every investigated year. The summer balance determines the annual balance. Compared to regional mean geodetic mass-balance rates in the Nepalese Himalaya, the mean mass-balance rate of Rikha Samba Glacier is in a similar range, and the mean mass-balance rate of Yala Glacier is more negative because of the small and low-lying accumulation area. During the study period, a change of Yala Glacier's surface topography has been observed with glacier thinning and downwasting. The retreat rates of Rikha Samba Glacier are higher than for Yala Glacier. From 1989 to 2013, Rikha Samba Glacier retreated 431 m (−18.0 m a−1), and from 1974 to 2016 Yala Glacier retreated 346 m (−8.2 m a−1). The data of the annual and seasonal mass balances, point mass balance, geodetic mass balance, and length changes are accessible from the World Glacier Monitoring Service (WGMS, 2021), https://doi.org/10.5904/wgms-fog-2021-05.

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Reanalysis of the US Geological Survey Benchmark Glaciers: long-term insight into climate forcing of glacier mass balance

Journal of Glaciology ◽

10.1017/jog.2019.66 ◽

2019 ◽

Vol 65 (253) ◽

pp. 850-866 ◽

Cited By ~ 14

Author(s):

Shad O'Neel ◽

Christopher McNeil ◽

Louis C. Sass ◽

Caitlyn Florentine ◽

Emily H. Baker ◽

...

Keyword(s):

Mass Loss ◽

Mass Balance ◽

Climate Forcing ◽

Geological Survey ◽

Glacier Mass Balance ◽

Climate Signal ◽

Calibration Methods ◽

Uncertainty Estimates ◽

The Us

AbstractMountain glaciers integrate climate processes to provide an unmatched signal of regional climate forcing. However, extracting the climate signal via intercomparison of regional glacier mass-balance records can be problematic when methods for extrapolating and calibrating direct glaciological measurements are mixed or inconsistent. To address this problem, we reanalyzed and compared long-term mass-balance records from the US Geological Survey Benchmark Glaciers. These five glaciers span maritime and continental climate regimes of the western United States and Alaska. Each glacier exhibits cumulative mass loss since the mid-20th century, with average rates ranging from −0.58 to −0.30 m w.e. a−1. We produced a set of solutions using different extrapolation and calibration methods to inform uncertainty estimates, which range from 0.22 to 0.44 m w.e. a−1. Mass losses are primarily driven by increasing summer warming. Continentality exerts a stronger control on mass loss than latitude. Similar to elevation, topographic shading, snow redistribution and glacier surface features often exert important mass-balance controls. The reanalysis underscores the value of geodetic calibration to resolve mass-balance magnitude, as well as the irreplaceable value of direct measurements in contributing to the process-based understanding of glacier mass balance.

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21st-century increase in glacier mass loss in the Wrangell Mountains, Alaska, USA, from airborne laser altimetry and satellite stereo imagery

Journal of Glaciology ◽

10.3189/2014jog13j119 ◽

2014 ◽

Vol 60 (220) ◽

pp. 283-293 ◽

Cited By ~ 20

Author(s):

Indrani Das ◽

Regine Hock ◽

Etienne Berthier ◽

Craig S. Lingle

Keyword(s):

Mass Loss ◽

Mass Balance ◽

High Elevation ◽

Center Line ◽

Laser Altimetry ◽

Tidewater Glaciers ◽

Airborne Laser ◽

Digital Elevation ◽

Stereo Imagery ◽

Elevation Model

AbstractAlaskan glaciers are among the largest regional contributors to sea-level rise in the latter half of the 20th century. Earlier studies have documented extensive and accelerated ice wastage in most regions of Alaska. Here we study five decades of mass loss on high-elevation, land-terminating glaciers of the Wrangell Mountains (~ 4900 km2) in central Alaska based on airborne center-line laser altimetry data from 2000 and 2007, a digital elevation model (DEM) from ASTER and SPOT5, and US Geological Survey topographic maps from 1957. The regional mass-balance estimates derived from center-line laser altimetry profiles using two regional extrapolation techniques agree well with that from DEM differencing. Repeat altimetry measurements reveal accelerated mass loss over the Wrangell Mountains, with the regional mass-balance rate evolving from –0.07 ± 0.19 m w.e. a–1 during 1957–2000 to –0.24 ± 0.16 m w.e. a–1 during 2000–07. Nabesna, the largest glacier in this region (˜1056 km2), lost mass four times faster during 2000–07 than during 1957–2000. Although accelerated, the mass change over this region is slower than in other glacierized regions of Alaska, particularly those with tidewater glaciers. Together, our laser altimetry and satellite DEM analyses demonstrate increased wastage of these glaciers during the last 50 years.

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