Preprints
Filtering by Subject: Glaciology
Tracking glacier surge evolution using interferometric SAR coherence — examples from Svalbard
Published: 2024-10-14
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
We present a practically simple methodology for tracking glacier surge onset and evolution using interferometric Synthetic Aperture Radar (InSAR) coherence. Detecting surges early and monitoring their build-up is interesting for a multitude of scientific and safety-related aspects. We show that InSAR coherence maps allow the detection of surge-related instability on Svalbard many years before [...]
Structural weaknesses in ice mélange revealed by high resolution ICEYE SAR imagery
Published: 2024-10-08
Subjects: Glaciology, Physical Sciences and Mathematics
The mixture of icebergs and sea ice in tidewater glacier fjords, known as ice mélange, is postulated to impact iceberg calving directly through physical buttressing and indirectly through freshwater fluxes altering fjord circulation. In this contribution, we assess the textural characteristics of ice mélange in summer and winter at the terminus of Helheim Glacier in Greenland using high [...]
Landscape evolution of the Black Forest: From the Variscan orogeny to the modern era
Published: 2024-09-28
Subjects: Geomorphology, Glaciology, Soil Science
With a maximum elevation of 1493 m above sea-level, the Black Forest (Schwarzwald in German) is the second highest mountain range in Germany. It is subdivided in three main natural regions, the northern, central, and southern Black Forest. The Variscan basement of the Black Forest consists of plutonic and metamorphic rocks. Sedimentary rocks formed during the Mesozoic under marine and terrestrial [...]
Greenland Ice Sheet wide supraglacial lake evolution and dynamics: insights from the 2018 and 2019 melt seasons
Published: 2024-07-29
Subjects: Glaciology
Supraglacial lakes on the Greenland Ice Sheet (GrIS) can impact both the ice sheet surface mass balance and ice dynamics. Thus, understanding the evolution and dynamics of supraglacial lakes is important to provide improved parameterizations for ice sheet models to enable better projections of future GrIS changes. In this study, we utilize the growing inventory of optical and microwave satellite [...]
Sensitivity of modelled mass balance and runoff to representations of debris and accumulation on the Kaskawulsh Glacier, Yukon, Canada
Published: 2024-07-19
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Runoff from glaciers accounts for half the total freshwater discharge to the Gulf of Alaska, with glacier contributions to streamflow changing as mass loss accelerates. We reconstruct the 1980–2022 mass balance, runoff and water budget of the 70% glacierized Kaskawulsh River Headwaters in Yukon, Canada, using an enhanced temperature-index model driven by downscaled and bias-corrected reanalysis [...]
Modeling sediment compaction beneath ice lenses during frost heave
Published: 2024-07-13
Subjects: Applied Mathematics, Earth Sciences, Glaciology, Hydrology, Physical Sciences and Mathematics, Soil Science
Frost heave occurs when the ground swells during freezing conditions due to the growth of ice lenses in the subsurface. The mechanics of ice-infiltrated sediment, or frozen fringe, influences the formation and evolution of ice lenses. As the frozen fringe thickens during freezing, progressive unloading can result in dilation of the pore space and the formation of new ice lenses. Compaction can [...]
Uranium-series isotopes as tracers of physical and chemical weathering in glacial sediments from Taylor Valley, Antarctica
Published: 2024-07-04
Subjects: Earth Sciences, Geochemistry, Glaciology, Soil Science
The McMurdo Dry Valleys of Antarctica formed by extensive glacial erosion, yet currently exhibit hyperarid polar conditions characterized by limited chemical and physical weathering. Efficient chemical weathering occurs when moisture is available, and polythermal subglacial conditions may accommodate ongoing mechanical weathering and valley incision. Taylor Valley hosts several Pleistocene [...]
Mechanisms for upstream migration of firn aquifer drainage: preliminary observations of Helheim Glacier, Greenland
Published: 2024-07-03
Subjects: Glaciology
Surface meltwater can influence subglacial hydrology and ice dynamics if it reaches the ice sheet’s base. Firn aquifers store meltwater and drain into wide crevasses marking the aquifer’s downstream boundary, indicating water from firn aquifers drives hydrofracture to establish the upglacier-most surface-to-bed hydraulic connections. Yet, sparse observations limit our understanding of the [...]
Increasing precipitation will offset the impact of warming air temperatures on glacier volume loss in the monsoon-influenced Himalaya until 2100 CE
Published: 2024-06-27
Subjects: Glaciology
Himalayan glaciers are projected to shrink by over 50% this century due to rising air temperatures. However, the impact of future precipitation change on glacier evolution remains uncertain. Here we explore these precipitation effects by simulating the future evolution of Khumbu Glacier in the monsoon-influenced Himalaya until 2300 CE. Khumbu Glacier is committed by historical warming to volume [...]
Fracture criteria and tensile strength for natural glacier ice calibrated from remote sensing observations of Antarctic ice shelves
Published: 2024-06-24
Subjects: Glaciology
The conditions under which ice fractures and calves icebergs from Antarctic ice shelves are poorly understood due largely to a lack of relevant observations. Though previous studies have estimated the stresses at which ice fractures in the laboratory and through sparse observations, there remains significant uncertainty in the applicability of these results to naturally deforming glacier ice on [...]
Automatic identification of streamlined subglacial bedforms using machine learning: an open-source Python approach
Published: 2024-06-16
Subjects: Geomorphology, Glaciology, Statistical Models
Subglacial processes exert a major control on ice streaming. Constraining subglacial conditions thus allows for more accurate predictions of ice mass loss. Due to the difficulty in observing large‐scale conditions of the modern subglacial environment, we turn to geologic records of ice streaming in deglaciated environments. Morphometric values of streamlined subglacial bedforms provide valuable [...]
Investigating the Dynamic History of a Promontory Ice Rise using Radar Data
Published: 2024-06-07
Subjects: Geophysics and Seismology, Glaciology
Ice rises hold valuable records revealing the ice dynamics and climatic history of Antarctic coastal areas from the Last Glacial Maximum to today. This history is often reconstructed from isochrone radar stratigraphy and simulations focusing on Raymond arch evolution beneath the divides. However, this relies on complex ice-flow models where many parameters are unconstrained by observations. Our [...]
Unique In-situ Measurements from Greenland Fjord Show Winter Freshening by Subglacial Melt
Published: 2024-05-08
Subjects: Earth Sciences, Glaciology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Earth Sciences, Physical Sciences and Mathematics
The interaction between glacier fronts and ocean waters is one of the key uncertainties for projecting future ice mass loss. Direct observations at glacier fronts are sparse but studies indicate that the magnitude and timing of freshwater fluxes are crucial in determining fjord circulation, ice frontal melt and ecosystem habitability. Particularly wintertime dynamics are severely understudied due [...]
The role of thermal notch erosion in forcing localised calving failure and short-term increases in velocity at a lake-terminating glacier in southeast Iceland
Published: 2024-04-10
Subjects: Glaciology
We utilised repeat high-resolution UAV-SfM surveys, alongside terrestrial photography acquired in-situ, to investigate, for the first time, how localised calving failure can drive short-term increases in velocity at a lake-terminating glacier. This data was acquired over five days in early July 2019, and across 11 days in July 2021, to provide insights into a suite of processes that have been [...]
Concepts and capabilities of the Instructed Glacier Model
Published: 2024-04-05
Subjects: Glaciology
We present the concept and capabilities of IGM (https://github.com/jouvetg/igm), a Python-based modeling tool designed for efficiently simulating glacier evolution across various scales. IGM integrates ice thermomechanics, climate-driven surface mass balance, mass conservation, and other processes. Within IGM, the update of all physical model components involves a series of mathematical [...]