scholarly journals Mass balance of Trambau Glacier, Rolwaling region, Nepal Himalaya: in-situ observations, long-term reconstruction and mass-balance sensitivity

2019 ◽  
Vol 65 (252) ◽  
pp. 605-616 ◽  
Author(s):  
SOJIRO SUNAKO ◽  
KOJI FUJITA ◽  
AKIKO SAKAI ◽  
RIJAN B. KAYASTHA
Keyword(s):  
Mass Balance ◽  
High Elevation ◽  
Climatic Conditions ◽  
Balance Model ◽  
Glacier Mass Balance ◽  
Balance Study ◽  
Nepal Himalaya ◽  
In Situ Data

ABSTRACTWe conducted a mass-balance study of debris-free Trambau Glacier in the Rolwaling region, Nepal Himalaya, which is accessible to 6000 m a.s.l., to better understand mass-balance processes and the effect of precipitation on these processes on high-elevation Himalayan glaciers. Continuous in situ meteorological and mass-balance observations that spanned the three melt seasons from May 2016 are reported. An energy- and mass-balance model is also applied to evaluate its performance and sensitivity to various climatic conditions. Glacier-wide mass balances ranging from −0.34 ± 0.38 m w.e. in 2016 to −0.82 ± 0.53 m w.e. in 2017/18 are obtained by combining the observations with model results for the areas above the highest stake. The estimated long-term glacier mass balance, which is reconstructed using the ERA-Interim data calibrated with in situ data, is −0.65 ± 0.39 m w.e. a−1for the 1980–2018 period. A significant correlation with annual precipitation (r= 0.77,p< 0.001) is observed, whereas there is no discernible correlation with summer mean air temperature. The results indicate the continuous mass loss of Trambau Glacier over the last four decades, which contrasts with the neighbouring Mera Glacier in balance.

scholarly journals Favorable climatic regime for maintaining the present-day geometry of the Gregoriev Glacier, Inner Tien Shan

2011 ◽  
Vol 5 (3) ◽  
pp. 539-549 ◽  
Author(s):  
K. Fujita ◽  
N. Takeuchi ◽  
S. A. Nikitin ◽  
A. B. Surazakov ◽  
S. Okamoto ◽  
...  
Keyword(s):  
Mass Balance ◽  
Meteorological Data ◽  
Tien Shan ◽  
Balance Model ◽  
Glacier Mass Balance ◽  
Current State ◽  
Climatic Regime ◽  
Good Agreement

Abstract. We conducted 2 yr (2005–2007) of in situ meteorological and glaciological observations on the Gregoriev Glacier, a flat-top glacier within the Inner Tien Shan, Kyrgyzstan. Relative carrier-phase GPS surveys reveal a vertical lowering at the summit of the glacier. Based on snow density data and an energy-mass balance model, we estimate that the annual precipitation and summer mean temperature required to maintain the glacier in the current state are 289 mm and −3.8 °C at the glacier summit (4600 m a.s.l.), respectively. The good agreement between dynamically derived precipitation and the long-term observed precipitation at a nearby station in the Tien Shan (296 mm at 3614 m a.s.l. for the period 1930–2002) suggests that the glacier has been in a near steady-state in terms of mass supply. The glacier mass-balance, reconstructed based on meteorological data from the Tien Shan station for the past 80 yr, explains the observed fluctuations in glacier extent, particularly the negative mass balance in the 1990s.

scholarly journals Ideal climatic variables for the present-day geometry of the Gregoriev Glacier, Inner Tien Shan, Kyrgyzstan, derived from GPS data and energy-mass balance measurements

2011 ◽  
Vol 5 (2) ◽  
pp. 855-883
Author(s):  
K. Fujita ◽  
N. Takeuchi ◽  
S. A. Nikitin ◽  
A. B. Surazakov ◽  
S. Okamoto ◽  
...  
Keyword(s):  
Mass Balance ◽  
Meteorological Data ◽  
Vertical Surface ◽  
Tien Shan ◽  
Balance Model ◽  
Glacier Mass Balance ◽  
Differential Gps ◽  
Good Agreement

Abstract. We conducted 2 yr (2005–2007) of in situ meteorological and glaciological observations on the Gregoriev Glacier, a flat-top glacier within the Inner Tien Shan, Kyrgyzstan. Differential GPS surveys reveal a vertical surface deletion at the summit of the glacier. Based on snow density data and an energy-mass balance model, we estimate that the annual precipitation and summer mean temperature required to maintain the glacier in the modern state are 289 mm and −3.85 °C at the glacier summit (4600 m above sea level, a.s.l.), respectively. The good agreement between the long-term estimated and observed precipitation at a nearby station in the Tien Shan (292 mm at 3614 m a.s.l. for the period 1930–2002) suggests that the glacier dynamics have been regulated by the long-term average accumulation. The glacier mass-balance, reconstructed based on meteorological data from the Tien Shan station for the past 80 yr, explains the observed fluctuations in glacier extent, particularly the negative mass balance in the 1990s.

scholarly journals The influence of changes in glacier extent and surface elevation on modeled mass balance

2010 ◽  
Vol 4 (2) ◽  
pp. 737-766 ◽  
Author(s):  
F. Paul
Keyword(s):  
Climate Change ◽  
Mass Balance ◽  
Climate Change Impacts ◽  
Climatic Conditions ◽  
Swiss Alps ◽  
Surface Elevation ◽  
Balance Model ◽  
Glacier Mass Balance ◽  
Atmospheric Conditions

Abstract. Glaciers are widely recognized as unique demonstration objects for climate change impacts, mostly due to the strong change of glacier length in response to small climatic changes. However, glacier mass balance as the direct response to the annual atmospheric conditions can be better interpreted in meteorological terms. When the climatic signal is deduced from long-term mass balance data, changes in glacier geometry (i.e. surface extent and elevation) must be considered as such adjustments form an essential part of the glacier reaction to new climatic conditions. In this study, a set of modeling experiments is performed to assess the influence of changes in glacier geometry on mass balance for constant climatic conditions. The calculations are based on a simplified distributed energy/mass balance model in combination with information on glacier extent and surface elevation for the years 1850 and 1973/1985 for a larger sample of glaciers in the Swiss Alps. The results reveal that about 50–70% of the glacier reaction to climate change (here a one degree increase in temperature) is "hidden" in the geometric adjustment, while only 30–50% can be measured as the long-term mean mass balance. Thereby, changes in glacier extent alone have an even stronger effect, but they are partly compensated for by a lowered surface elevation which gives on average a slightly more negative balance despite an increase of topographic shading. In view of several additional reinforcement feedbacks that are observed in periods of strong glacier decline, it seems that the climatic interpretation of mass balance data is also rather complex.

scholarly journals The influence of changes in glacier extent and surface elevation on modeled mass balance

2010 ◽  
Vol 4 (4) ◽  
pp. 569-581 ◽  
Author(s):  
F. Paul
Keyword(s):  
Climate Change ◽  
Mass Balance ◽  
Climate Change Impacts ◽  
Climatic Conditions ◽  
Swiss Alps ◽  
Surface Elevation ◽  
Balance Model ◽  
Glacier Mass Balance ◽  
Atmospheric Conditions

Abstract. Glaciers are widely recognized as unique demonstration objects for climate change impacts, mostly due to the strong change of glacier length in response to small climatic changes. However, glacier mass balance as the direct response to the annual atmospheric conditions can be better interpreted in meteorological terms. When the climatic signal is deduced from long-term mass balance data, changes in glacier geometry (i.e. surface extent and elevation) must be considered as such adjustments form an essential part of the glacier reaction to new climatic conditions. In this study, a set of modelling experiments is performed to assess the influence of changes in glacier geometry on mass balance for constant climatic conditions. The calculations are based on a simplified distributed energy/mass balance model in combination with information on glacier extent and surface elevation for the years 1850 and 1973/1985 for about 60 glaciers in the Swiss Alps. The results reveal that over this period about 50–70% of the glacier reaction to climate change (here a one degree increase in temperature) is "hidden" in the geometric adjustment, while only 30–50% can be measured as the long-term mean mass balance. For larger glaciers, the effect of the areal change is partly reduced by a lowered surface elevation, which results in a slightly more negative balance despite a potential increase of topographic shading. In view of several additional reinforcement feedbacks that are observed in periods of strong glacier decline, it seems that the climatic interpretation of long-term mass balance data is rather complex.

scholarly journals Sensitivity of mountain glacier mass balance to changes in bare-ice albedo

2017 ◽  
Vol 58 (75pt2) ◽  
pp. 119-129 ◽  
Author(s):  
Kathrin Naegeli ◽  
Matthias Huss
Keyword(s):  
Mass Balance ◽  
Balance Model ◽  
Glacier Mass Balance ◽  
Landsat 8 ◽  
Glacier Surface ◽  
Mountain Glacier ◽  
Albedo Feedback ◽  
In Situ Data ◽  
The Impact ◽  
Near Future

ABSTRACT Albedo is an important parameter in the energy balance of bare-ice surfaces and modulates glacier melt rates. The prolongation of the ablation period enforces the albedo feedback and highlights the need for profound knowledge on impacts of bare-ice albedo on glacier mass balance. In this study, we assess the mass balance sensitivity of 12 Swiss glaciers with abundant long-term in-situ data on changes in bare-ice albedo. We use pixel-based bare-ice albedo derived from Landsat 8. A distributed mass-balance model is applied to the period 1997–2016 and experiments are performed to assess the impact of albedo changes on glacier mass balance. Our results indicate that glacier-wide mass-balance sensitivities to changes in bare-ice albedo correlate strongly with mean annual mass balances (r 2 = 0.81). Large alpine glaciers react more sensitively to bare-ice albedo changes due to their ablation areas being situated at lower elevations. We find average sensitivities of glacier-wide mass balance of −0.14 m w.e. a−1 per 0.1 albedo decrease. Although this value is considerably smaller than sensitivity to air temperature change, we stress the importance of the enhanced albedo feedback that will be amplified due to atmospheric warming and a suspected darkening of glacier surface in the near future.

scholarly journals Forcing a Distributed Glacier Mass Balance Model with the Regional Climate Model REMO. Part I: Climate Model Evaluation

2010 ◽  
Vol 23 (6) ◽  
pp. 1589-1606 ◽  
Author(s):  
Sven Kotlarski ◽  
Frank Paul ◽  
Daniela Jacob
Keyword(s):  
Regional Climate Model ◽  
Mass Balance ◽  
Climate Model ◽  
Regional Climate ◽  
Global Radiation ◽  
High Elevation ◽  
Balance Model ◽  
Future Climate Change ◽  
Glacier Mass Balance ◽  
Mass Balance Model

Abstract A coupling interface between the regional climate model REMO and a distributed glacier mass balance model is presented in a series of two papers. The first part describes and evaluates the reanalysis-driven regional climate simulation that is used to force a mass balance model for two glaciers of the Swiss mass balance network. The detailed validation of near-surface air temperature, precipitation, and global radiation for the European Alps shows that the basic spatial and temporal patterns of all three parameters are reproduced by REMO. Compared to the Climatic Research Unit (CRU) dataset, the Alpine mean temperature is underestimated by 0.34°C. Annual precipitation shows a positive bias of 17% (30%) with respect to the uncorrected gridded ALP-IMP (CRU) dataset. A number of important and systematic model biases arise in high-elevation regions, namely, a negative temperature bias in winter, a bias of seasonal precipitation (positive or negative, depending on gridbox altitude and season), and an underestimation of springtime and overestimation of summertime global radiation. These can be expected to have a strong effect on the simulated glacier mass balance. It is recommended to account for these shortcomings by applying correction procedures before using the RCM output for subsequent mass balance modeling. Despite the obvious model deficiencies in high-elevation regions, the new interface broadens the scope of application of glacier mass balance models and will allow for a straightforward assessment of future climate change impacts.

scholarly journals Problems with the retrieval of glacier net surface balance from SAR imagery

2005 ◽  
Vol 42 ◽  
pp. 209-216 ◽  
Author(s):  
Ian A. Brown ◽  
Per Klingbjer ◽  
Andy Dean
Keyword(s):  
Mass Balance ◽  
Glacier Mass Balance ◽  
In Situ Data ◽  
Amplitude Data ◽  
Multi Temporal ◽  
Geophysical Processes ◽  
Sar Imagery ◽  
Arctic Glacier ◽  
Surface Balance

AbstractThere are relatively few comparisons between synthetic aperture radar (SAR) observations and glacier mass-balance measurements. More typically, SAR has been deployed to identify changes in the end-of-summer snowline and other facies boundaries. In this paper, we analyze the geophysical processes affecting SAR amplitude data over two Arctic glacier systems in northern Scandinavia to assess the potential of SAR observations for the retrieval of surface balance parameters. Using a backscatter model and in situ data, we identify the controls on SAR imagery in terms of mass-balance measurement and discuss the glaciological parameters which can reasonably be derived from multi-temporal SAR data. Our results show that amplitude SAR imagery, in the absence of in situ measurements, is not capable of providing meaningful mass-balance data. We show that backscatter from temperate glaciers is affected primarily by snow grain-size and density, and therefore processes such as firnification or depth-hoar formation can complicate the analysis of imagery. We conclude that SAR imagery over temperate glaciers can provide valuable proxy information but not direct mass-balance terms.

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

2015 ◽  
Vol 11 (11) ◽  
pp. 1575-1586 ◽  
Author(s):  
C. Bravo ◽  
M. Rojas ◽  
B. M. Anderson ◽  
A. N. Mackintosh ◽  
E. Sagredo ◽  
...  
Keyword(s):  
New Zealand ◽  
Mass Balance ◽  
Southern Hemisphere ◽  
Austral Summer ◽  
Climatic Conditions ◽  
Equilibrium Line ◽  
Balance Model ◽  
Glacier Mass Balance ◽  
Mass Balance Model ◽  
Climate Conditions

Abstract. Glacier behaviour during the mid-Holocene (MH, 6000 years BP) in the Southern Hemisphere provides observational data to constrain our understanding of the origin and propagation of palaeoclimate signals. In this study we examine the climatic forcing of glacier response in the MH by evaluating modelled glacier equilibrium line altitudes (ELAs) and climatic conditions during the MH compared with pre-industrial time (PI, year 1750). We focus on the middle latitudes of the Southern Hemisphere, specifically Patagonia and the South Island of New Zealand. Climate conditions for the MH were obtained from PMIP2 model simulations, which in turn were used to force a simple glacier mass balance model to simulate changes in ELA. In Patagonia, the models simulate colder conditions during the MH in austral summer (−0.2 °C), autumn (−0.5 °C), and winter (−0.4), and warmer temperatures (0.2 °C) during spring. In the Southern Alps the models show colder MH conditions in autumn (−0.7 °C) and winter (−0.4 °C), warmer conditions in spring (0.3 °C), and no significant change in summer temperature. Precipitation does not show significant changes but exhibits a seasonal shift, with less precipitation from April to September and more precipitation from October to April during the MH in both regions. The mass balance model simulates a climatic ELA that is 15–33 m lower during the MH compared with PI conditions. We suggest that the main causes of this difference are driven mainly by colder temperatures associated with the MH simulation. Differences in temperature have a dual effect on glacier mass balance: (i) less energy is available for ablation during summer and early autumn and (ii) lower temperatures cause more precipitation to fall as snow rather than rain in late autumn and winter, 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 by 6000 years BP in South America and New Zealand.

scholarly journals Re-analysis of seasonal mass balance at Abramov glacier 1968–2014

2015 ◽  
Vol 61 (230) ◽  
pp. 1103-1117 ◽  
Author(s):  
Martina Barandun ◽  
Matthias Huss ◽  
Leo Sold ◽  
Daniel Farinotti ◽  
Erlan Azisov ◽  
...  
Keyword(s):  
Mass Balance ◽  
Balance Model ◽  
Glacier Mass Balance ◽  
The Past ◽  
Seasonal Time Series ◽  
Direct Measurements ◽  
Spatially Distributed ◽  
Terrestrial Network ◽  
Ground Penetrating

AbstractAbramov glacier, located in the Pamir Alay, Kyrgyzstan, is a reference glacier within the Global Terrestrial Network for Glaciers. Long-term glaciological measurements exist from 1968 to 1998 and a mass-balance monitoring programme was re-established in 2011. In this study we re-analyse existing mass-balance data and use a spatially distributed mass-balance model to provide continuous seasonal time series of glacier mass balance covering the period 1968–2014. The model is calibrated to seasonal mass-balance surveys and then applied to the period with no measurements. Validation and recalibration is carried out using snowline observations derived from satellite imagery and, after 2011, also from automatic terrestrial camera images. We combine direct measurements, remote observations and modelling. The results are compared to geodetic glacier volume change over the past decade and to a ground-penetrating radar survey in the accumulation zone resolving several layers of accumulation. Previously published geodetic mass budget estimates for Abramov glacier suggest a close-to-zero mass balance for the past decade, which contradicts our results. We find a low plausibility for equilibrium conditions over the past 15 years. Instead, we suggest that the glacier’s sensitivity to increased summer air temperature is decisive for the substantial mass loss during the past decade.

scholarly journals Mass balances of Yala and Rikha Samba Glacier, Nepal from 2000 to 2017

2020 ◽  
Author(s):  
Dorothea Stumm ◽  
Sharad Prasad Joshi ◽  
Tika Ram Gurung ◽  
Gunjan Silwal
Keyword(s):  
Mass Balance ◽  
Glacier Mass Balance ◽  
Mass Balances ◽  
Nepal Himalaya ◽  
Essential Variable ◽  
Monitoring Strategies ◽  
Glacier Length ◽  
Length Changes ◽  
Monitoring Service

Abstract. The direct or glaciological method is an integral part of international glacier monitoring strategies, and the mass balance is an essential variable to describe the climate system and model runoff. In 2011, we established two glacier mass balance programmes on Yala and Rikha Samba Glacier in the Nepal Himalaya. Here we present the methods and data that we ingested into the database of the World Glacier Monitoring Service. We present glacier length changes and the annual mass balances for the first six mass balance years for both glaciers. For Yala Glacier we additionally present the mass balance of seasonal in situ measurements and the mass balance from 2000 to 2012 analysed with the geodetic method. The annual mass balance rates of Yala Glacier from 2000 to 2012 and from 2011 to 2017 are −0.74 ± 0.53 m and −0.74 ± 0.28 m w.e. a−1, and for Rikha Samba Glacier from 2011 to 2017 −0.39 ± 0.32 m w.e. a−1. The mass loss for the period 2011 to 2017 for Yala and Rikha Samba Glacier −4.44 ± 0.69 m w.e. and −2.34 ± 0.79 m w.e., respectively. The winter balance of Yala Glacier is positive in every investigated year, but the negative summer balance determines the annual balance. The mass balance of Yala Glacier is more negative than on other glaciers in the region, mostly because of the small and low lying accumulation area. The mass balance of Rikha Samba Glacier is more positive than the other glaciers in the region, likely because of the large and high lying accumulation area. Due to the topography, the retreat rates of Rikha Samba Glacier are much higher than for Yala Glacier. From 1989 to 2013, Rikha Samba retreated 431 m (−18.0 m a−1), and from 1974 to 2016 Yala Glacier retreated 346 m (−8.2 m a−1). During the study period, a change of Yala Glacier's surface topography has been observed with glacier thinning and down wasting, which indicates the likely disappearance of Yala Glacier within this century. The datasets are freely accessible from WGMS (2020a): Fluctuations of Glaciers Database. World Glacier Monitoring Service, Zurich, Switzerland. http://dx.doi.org/10.5904/wgms-fog-2020-08.

Sign in / Sign up

Export Citation Format

Share Document