The Experts below are selected from a list of 117423 Experts worldwide ranked by ideXlab platform
Matthias Huss - One of the best experts on this subject based on the ideXlab platform.
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common climatic signal from Glaciers in the european alps over the last 50 years
Geophysical Research Letters, 2017Co-Authors: Christian Vincent, Stephan P Galos, Delphine Six, Andreas Bauder, Emmanuel Thibert, Martin Funk, Christoph Mayer, L Braun, Andrea Fischer, Matthias HussAbstract:Conventional glacier-wide mass balances are commonly used to study the effect of climate forcing on glacier melt. Unfortunately, the glacier-wide mass balances are also influenced by the glacier's dynamic response. Investigations on the effects of climate forcing on Glaciers can be largely improved by analyzing point mass balances. Using a statistical model, we have found that 52% of the year-to-year deviations in the point mass balances of six Glaciers distributed across the entire European Alps can be attributed to a common variability. Point mass balance changes reveal remarkable regional consistencies reaching 80% for Glaciers less than 10 km apart. Compared to the steady state conditions of the 1962–1982 period, the surface mass balance changes are −0.85 m water equivalent (w.e.) a−1 for 1983–2002 and −1.63 m w.e. a−1 for 2003–2013. This indicates a clear and regionally consistent acceleration of mass loss over recent decades over the entire European Alps.
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integrating a glacier retreat model into a hydrological model case studies of three glacierised catchments in norway and himalayan region
Journal of Hydrology, 2015Co-Authors: Stein Beldring, Matthias Huss, Kjetil Melvold, Sharad K. JainAbstract:Summary Glaciers are crucial in many countries where meltwater from Glaciers is an important source of water for drinking water supply, irrigation, hydropower generation and the ecological system. Glaciers are also important indicators of climate change. They have been significantly altered due to the global warming and have subsequently affected the regional hydrological regime. However, few models are able to parameterise the dynamics of the glacier system and consequent runoff processes in glacier fed basins with desirable performance measures. To narrow this gap, we have developed an integrated approach by coupling a hydrological model (HBV) and a glacier retreat model ( Δ h -parameterisation) and tested this approach in three basins with different glacier coverage and subject to different climate and hydrologic regimes. Results show that the coupled model is able to give satisfactory estimations of runoff and glacier mass balance in the Nigardsbreen basin where the measured data are available to verify the results. In addition, the model can provide maps of snowpack distribution and estimate runoff components from Glaciers.
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Integrating a glacier retreat model into a hydrological model – Case studies of three glacierised catchments in Norway and Himalayan region
Journal of Hydrology, 2015Co-Authors: Stein Beldring, Matthias Huss, Kjetil Melvold, Sharad K. JainAbstract:Summary Glaciers are crucial in many countries where meltwater from Glaciers is an important source of water for drinking water supply, irrigation, hydropower generation and the ecological system. Glaciers are also important indicators of climate change. They have been significantly altered due to the global warming and have subsequently affected the regional hydrological regime. However, few models are able to parameterise the dynamics of the glacier system and consequent runoff processes in glacier fed basins with desirable performance measures. To narrow this gap, we have developed an integrated approach by coupling a hydrological model (HBV) and a glacier retreat model ( Δ h -parameterisation) and tested this approach in three basins with different glacier coverage and subject to different climate and hydrologic regimes. Results show that the coupled model is able to give satisfactory estimations of runoff and glacier mass balance in the Nigardsbreen basin where the measured data are available to verify the results. In addition, the model can provide maps of snowpack distribution and estimate runoff components from Glaciers.
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a database of worldwide glacier thickness observations
Global and Planetary Change, 2014Co-Authors: Isabelle Gartnerroer, Tobias Knecht, Horst Machguth, Kathrin Naegeli, Matthias Huss, Michael ZempAbstract:Abstract One of the grand challenges in glacier research is to assess the total ice volume and its global distribution. Over the past few decades the compilation of a world glacier inventory has been well-advanced both in institutional set-up and in spatial coverage. The inventory is restricted to glacier surface observations. However, although thickness has been observed on many Glaciers and ice caps around the globe, it has not yet been published in the shape of a readily available database. Here, we present a standardized database of glacier thickness observations compiled by an extensive literature review and from airborne data extracted from NASA's Operation IceBridge. This database contains ice thickness observations from roughly 1100 Glaciers and ice caps including 550 glacier-wide estimates and 750,000 point observations. A comparison of these observational ice thicknesses with results from area- and slope-dependent approaches reveals large deviations both from the observations and between different estimation approaches. For Glaciers and ice caps all estimation approaches show a tendency to overestimation. For Glaciers the median relative absolute deviation lies around 30% when analyzing the different estimation approaches. This initial database of glacier and ice caps thickness will hopefully be further enlarged and intensively used for a better understanding of the global glacier ice volume and its distribution.
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The length of the Glaciers in the world: a straightforward method for the automated calculation of glacier center lines
The Cryosphere Discussions, 2014Co-Authors: Horst Machguth, Matthias HussAbstract:Abstract. Glacier length is an important measure of glacier geometry but global glacier inventories are mostly lacking length data. Only recently semi-automated approaches to measure glacier length have been developed and applied regionally. Here we present a first global assessment of glacier length using a fully automated method based on glacier surface slope, distance to the glacier margins and a set of trade-off functions. The method is developed for East Greenland, evaluated for the same area as well as for Alaska, and eventually applied to all ∼200 000 Glaciers around the globe. The evaluation highlights accurately calculated glacier length where DEM quality is good (East Greenland) and limited precision on low quality DEMs (parts of Alaska). Measured length of very small Glaciers is subject to a certain level of ambiguity. The global calculation shows that only about 1.5% of all Glaciers are longer than 10 km with Bering Glacier (Alaska/Canada) being the longest glacier in the world at a length of 196 km. Based on model output we derive global and regional area-length scaling laws. Differences among regional scaling parameters appear to be related to characteristics of topography and glacier mass balance. The present study adds glacier length as a central parameter to global glacier inventories. Global and regional scaling laws might proof beneficial in conceptual glacier models.
M. S. Pelto - One of the best experts on this subject based on the ideXlab platform.
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Glacier annual balance measurement, forecasting and climate correlations, North Cascades, Washington 1984?2006
The Cryosphere, 2008Co-Authors: M. S. PeltoAbstract:North Cascade glacier annual balance measured on 10 Glaciers from 1984?2006 yielded mean annual balance (ba) of ?0.54 m/a, and ?12.38 m cumulatively. This is a significant loss for Glaciers that average 30?60 m in thickness, 20?40% of their entire volume. Two observed Glaciers, Lewis Glacier and Spider Glacier, no longer exist. The ba of North Cascade Glaciers is reliably calculated, correlation coefficient 0.91, using 1 April snowpack water equivalent and ablation season temperature. Utilizing ba from 10 Glaciers 1984?2006 and net balance (bn) from South Cascade 1960?2005, a set of forecast rules for glacier mass balance were derived utilizing October?April Pacific Decadal Oscillation and Multivariate El Nino Southern Oscillation index values. The forecast rules provide a correct assessment in 41 of the 46 years for South Cascade Glacier and 20 of 23 years for NCGCP Glaciers. Glacier annual balance forecasting is an important step for summer water resource management in glacier runoff dominated stream systems. The forecast for North Cascade Glaciers in 2007 is for a negative ba.
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Glacier annual balance measurement, prediction, forecasting and climate correlations, North Cascades, Washington 1984?2006
The Cryosphere Discussions, 2007Co-Authors: M. S. PeltoAbstract:North Cascade glacier annual balance measured on 10 Glaciers from 1984?2006 yielded mean annual balance (ba) of ?0.54 m/a, and ?12.38 m cumulatively. This is a significant loss for Glaciers that average 30?60 m in thickness, representing 20?40% of their entire volume. Two observed Glaciers, Lewis Glacier and Spider Glacier, no longer exist. The ba of North Cascade Glaciers is reliably calculated based on 1 April snowpack water equivalent and ablation season temperature. 1 May forecasting of ba using the Pacific Decadal Oscillation and the Multivariate El Nino Southern Oscillation circulation indices correctly determined the sign of mass balance in 42 of 47 years. Glacier annual balance forecasting is an important step for summer water resource management in glacier runoff dominated stream systems. The forecast for North Cascade Glaciers in 2007 is for a negative annual balance.
Sharad K. Jain - One of the best experts on this subject based on the ideXlab platform.
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integrating a glacier retreat model into a hydrological model case studies of three glacierised catchments in norway and himalayan region
Journal of Hydrology, 2015Co-Authors: Stein Beldring, Matthias Huss, Kjetil Melvold, Sharad K. JainAbstract:Summary Glaciers are crucial in many countries where meltwater from Glaciers is an important source of water for drinking water supply, irrigation, hydropower generation and the ecological system. Glaciers are also important indicators of climate change. They have been significantly altered due to the global warming and have subsequently affected the regional hydrological regime. However, few models are able to parameterise the dynamics of the glacier system and consequent runoff processes in glacier fed basins with desirable performance measures. To narrow this gap, we have developed an integrated approach by coupling a hydrological model (HBV) and a glacier retreat model ( Δ h -parameterisation) and tested this approach in three basins with different glacier coverage and subject to different climate and hydrologic regimes. Results show that the coupled model is able to give satisfactory estimations of runoff and glacier mass balance in the Nigardsbreen basin where the measured data are available to verify the results. In addition, the model can provide maps of snowpack distribution and estimate runoff components from Glaciers.
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Integrating a glacier retreat model into a hydrological model – Case studies of three glacierised catchments in Norway and Himalayan region
Journal of Hydrology, 2015Co-Authors: Stein Beldring, Matthias Huss, Kjetil Melvold, Sharad K. JainAbstract:Summary Glaciers are crucial in many countries where meltwater from Glaciers is an important source of water for drinking water supply, irrigation, hydropower generation and the ecological system. Glaciers are also important indicators of climate change. They have been significantly altered due to the global warming and have subsequently affected the regional hydrological regime. However, few models are able to parameterise the dynamics of the glacier system and consequent runoff processes in glacier fed basins with desirable performance measures. To narrow this gap, we have developed an integrated approach by coupling a hydrological model (HBV) and a glacier retreat model ( Δ h -parameterisation) and tested this approach in three basins with different glacier coverage and subject to different climate and hydrologic regimes. Results show that the coupled model is able to give satisfactory estimations of runoff and glacier mass balance in the Nigardsbreen basin where the measured data are available to verify the results. In addition, the model can provide maps of snowpack distribution and estimate runoff components from Glaciers.
Ann V. Rowan - One of the best experts on this subject based on the ideXlab platform.
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Changes in glacier surface cover on Baltoro glacier, Karakoram, north Pakistan, 2001–2012
Journal of Maps, 2016Co-Authors: Morgan J Gibson, Neil F. Glasser, Duncan J. Quincey, Ann V. Rowan, Tristram Irvine-fynnAbstract:The presence of supraglacial debris on Glaciers in the Himalaya-Karakoram affects the ablation rate of these Glaciers and their response to climatic change. To understand how supraglacial debris distribution and associated surface features vary spatially and temporally, geomorphological mapping was undertaken on Baltoro Glacier, Karakoram, for three time-separated images between 2001–2012. Debris is supplied to the glacier system through frequent but small landslides at the glacier margin that form lateral and medial moraines and less frequent but higher volume rockfall events which are more lobate and often discontinuous in form. Debris on the glacier surface is identified as a series of distinct lithological units which merge downglacier of the convergence area between the Godwin-Austen and Baltoro South tributary Glaciers. Debris distribution varies as a result of complex interaction between tributary Glaciers and the main glacier tongue, complicated further by surge events on some tributary Glaciers. Glacier flow dynamics mainly controls the evolution of a supraglacial debris layer. Identifying such spatial variability in debris rock type and temporal variability in debris distribution has implications for glacier ablation rate, affecting glacier surface energy balance. Accordingly, spatial and temporal variation in supraglacial debris should be considered when determining mass balance for these Glaciers through time.
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spatial variability in mass loss of Glaciers in the everest region central himalayas between 2000 and 2015
The Cryosphere, 2016Co-Authors: Owen King, Duncan J. Quincey, Jonathan L Carrivick, Ann V. RowanAbstract:Abstract. Region-wide averaging of Himalayan glacier mass change has masked any catchment or glacier-scale variability in glacier recession; thus the role of a number of glaciological processes in glacier wastage remains poorly understood. In this study, we quantify mass loss rates over the period 2000–2015 for 32 Glaciers across the Everest region and assess how future ice loss is likely to differ depending on glacier hypsometry. The mean mass balance of all 32 Glaciers in our sample was −0.52 ± 0.22 m water equivalent (w.e.) a−1. The mean mass balance of nine lacustrine-terminating Glaciers (−0.70 ± 0.26 m w.e. a−1) was 32 % more negative than land-terminating, debris-covered Glaciers (−0.53 ± 0.21 m w.e. a−1). The mass balance of lacustrine-terminating Glaciers is highly variable (−0.45 ± 0.13 to −0.91 ± 0.22 m w.e. a−1), perhaps reflecting glacial lakes at different stages of development. To assess the importance of hypsometry on glacier response to future temperature increases, we calculated current (Dudh Koshi – 0.41, Tama Koshi – 0.43, Pumqu – 0.37) and prospective future glacier accumulation area Ratios (AARs). IPCC AR5 RCP 4.5 warming (0.9–2.3 °C by 2100) could reduce AARs to 0.29 or 0.08 in the Tama Koshi catchment, 0.27 or 0.17 in the Dudh Koshi catchment and 0.29 or 0.18 in the Pumqu catchment. Our results suggest that glacial lake expansion across the Himalayas could expedite ice mass loss and the prediction of future contributions of glacial meltwater to river flow will be complicated by spatially variable glacier responses to climate change.
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modelling the feedbacks between mass balance ice flow and debris transport to predict the response to climate change of debris covered Glaciers in the himalaya
Earth and Planetary Science Letters, 2015Co-Authors: Ann V. Rowan, Duncan J. Quincey, David L Egholm, Neil F. GlasserAbstract:Many Himalayan Glaciers are characterised in their lower reaches by a rock debris layer. This debris insulates the glacier surface from atmospheric warming and complicates the response to climate change compared to Glaciers with clean-ice surfaces. Debris-covered Glaciers can persist well below the altitude that would be sustainable for clean-ice Glaciers, resulting in much longer timescales of mass loss and meltwater production. The properties and evolution of supraglacial debris present a considerable challenge to understanding future glacier change. Existing approaches to predicting variations in glacier volume and meltwater production rely on numerical models that represent the processes governing Glaciers with clean-ice surfaces, and yield conflicting results. We developed a numerical model that couples the flow of ice and debris and includes important feedbacks between debris accumulation and glacier mass balance. To investigate the impact of debris transport on the response of a glacier to recent and future climate change, we applied this model to a large debris-covered Himalayan glacier—Khumbu Glacier in Nepal. Our results demonstrate that supraglacial debris prolongs the response of the glacier to warming and causes lowering of the glacier surface in situ, concealing the magnitude of mass loss when compared with estimates based on glacierised area. Since the Little Ice Age, Khumbu Glacier has lost 34% of its volume while its area has reduced by only 6%. We predict a decrease in glacier volume of 8–10% by AD2100, accompanied by dynamic and physical detachment of the debris-covered tongue from the active glacier within the next 150 yr. This detachment will accelerate rates of glacier decay, and similar changes are likely for other debris-covered Glaciers in the Himalaya.
Stein Beldring - One of the best experts on this subject based on the ideXlab platform.
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integrating a glacier retreat model into a hydrological model case studies of three glacierised catchments in norway and himalayan region
Journal of Hydrology, 2015Co-Authors: Stein Beldring, Matthias Huss, Kjetil Melvold, Sharad K. JainAbstract:Summary Glaciers are crucial in many countries where meltwater from Glaciers is an important source of water for drinking water supply, irrigation, hydropower generation and the ecological system. Glaciers are also important indicators of climate change. They have been significantly altered due to the global warming and have subsequently affected the regional hydrological regime. However, few models are able to parameterise the dynamics of the glacier system and consequent runoff processes in glacier fed basins with desirable performance measures. To narrow this gap, we have developed an integrated approach by coupling a hydrological model (HBV) and a glacier retreat model ( Δ h -parameterisation) and tested this approach in three basins with different glacier coverage and subject to different climate and hydrologic regimes. Results show that the coupled model is able to give satisfactory estimations of runoff and glacier mass balance in the Nigardsbreen basin where the measured data are available to verify the results. In addition, the model can provide maps of snowpack distribution and estimate runoff components from Glaciers.
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Integrating a glacier retreat model into a hydrological model – Case studies of three glacierised catchments in Norway and Himalayan region
Journal of Hydrology, 2015Co-Authors: Stein Beldring, Matthias Huss, Kjetil Melvold, Sharad K. JainAbstract:Summary Glaciers are crucial in many countries where meltwater from Glaciers is an important source of water for drinking water supply, irrigation, hydropower generation and the ecological system. Glaciers are also important indicators of climate change. They have been significantly altered due to the global warming and have subsequently affected the regional hydrological regime. However, few models are able to parameterise the dynamics of the glacier system and consequent runoff processes in glacier fed basins with desirable performance measures. To narrow this gap, we have developed an integrated approach by coupling a hydrological model (HBV) and a glacier retreat model ( Δ h -parameterisation) and tested this approach in three basins with different glacier coverage and subject to different climate and hydrologic regimes. Results show that the coupled model is able to give satisfactory estimations of runoff and glacier mass balance in the Nigardsbreen basin where the measured data are available to verify the results. In addition, the model can provide maps of snowpack distribution and estimate runoff components from Glaciers.
