Preprints
Filtering by Subject: Glaciology
A Model Workflow for GeoDeepDive: Locating Pliocene and Pleistocene Ice-Rafted Debris
Published: 2021-07-02
Subjects: Earth Sciences, Glaciology, Sedimentology
Machine learning technology promises a more efficient and scalable approach to locating and aggregating data and information from the burgeoning scientific literature. Realizing this promise requires provision of applications, data resources, and the documentation of analytic workflows. GeoDeepDive provides a digital library comprising over 13 million peer-reviewed documents and the computing [...]
C:N:P stoichiometry in six distinct habitats of a glacier terminus in the Yangtze River Source Area
Published: 2021-07-01
Subjects: Biogeochemistry, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Glaciology, Life Sciences, Other Environmental Sciences, Sustainability
Glaciers are among the least explored environments on Earth, especially from a perspective of nutrient stoichiometry. In this study, we documented and compared the nutrient availabilities (concentrations) and composition (stoichiometric ratios) of nutrients (C, N, and P) in six distinct habitats of a glacier terminus in the Yangtze River Source area, including surface ice (SI), basal ice (BI), [...]
Deglaciation-enhanced mantle CO2 fluxes at Yellowstone imply positive climate feedback
Published: 2021-06-25
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Glaciology, Tectonics and Structure, Volcanology
The generation of mantle melts in response to decompression by glacial unloading has been linked to enhanced volcanic activity and volatile release in Iceland and in global eruptive records. However, it is unclear whether this process is also important in magmatically-active systems that do not show evidence of enhanced eruption rates. For example, the deglaciation of the Yellowstone ice cap did [...]
A fully-coupled 3D model of a large Greenlandic outlet glacier with evolving subglacial hydrology, frontal plume melting and calving
Published: 2021-06-25
Subjects: Glaciology
We present the first fully coupled 3D full-Stokes model of a tidewater glacier, incorporating ice flow, subglacial hydrology, plume-induced frontal melting and calving. We apply the model to Store Glacier (Sermeq Kujalleq) in west Greenland to simulate a year of high melt (2012) and one of low melt (2017). In terms of modelled hydrology, we find perennial channels extending 5 km inland from the [...]
Water acceleration in a supraglacial channel predicts locations of step-pool sequence formation
Published: 2021-04-20
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Supraglacial channels constitute an important part of the glacial hydrological system, both by influencing surface energy exchange as well as routing meltwater to eventually feed en- and subglacial drainage systems. Subglacial systems have received considerable scientific interest, but specific studies of supraglacial channels are sparse. This limited scientific understanding represents a missing [...]
Recrystallization of ice enhances the creep and vulnerability to fracture of ice shelves
Published: 2021-03-08
Subjects: Earth Sciences, Geophysics and Seismology, Glaciology, Physical Sciences and Mathematics
The initiation of fractures and fast flow in floating regions of Antarctica have the potential to destabilize large regions of the grounded ice sheet, leading to significant sea-level rise. While observations have shown rapid, localized deformation and damage in the margins of fast-flowing glaciers, there remain gaps in our understanding of how rapid deformation affects the viscosity and [...]
Numerical modeling of Earth's dynamic surface: a community approach
Published: 2021-02-14
Subjects: Civil and Environmental Engineering, Computer Sciences, Earth Sciences, Engineering, Environmental Engineering, Environmental Sciences, Geology, Geomorphology, Glaciology, Hydrology, Numerical Analysis and Scientific Computing, Other Environmental Sciences, Physical Sciences and Mathematics, Sedimentology, Soil Science, Stratigraphy
Computational modelling occupies a unique niche in Earth environmental sciences. Models serve not just as scientific technology and infrastructure, but also as digital containers of the scientific community's understanding of the natural world. As this understanding improves, so too must the associated software. This dual nature---models as both infrastructure and hypotheses---means that [...]
Ordination analysis in sedimentology, geochemistry and paleoenvironment - background, current trends and recommendations
Published: 2021-02-01
Subjects: Biogeochemistry, Earth Sciences, Environmental Indicators and Impact Assessment, Environmental Monitoring, Geochemistry, Geology, Geomorphology, Geophysics and Seismology, Glaciology, Multivariate Analysis, Oil, Gas, and Energy, Other Earth Sciences, Paleobiology, Paleontology, Sedimentology
Ordination is the name given to a group of methods used to analyze multiple variables without preceding hypotheses. Over the last few decades the use of these methods in Earth science in general, and notably in analyses of sedimentary sources, has dramatically increased. However, with limited resources oriented towards Earth scientists on the topic, the application of ordination analysis is at [...]
Half a century of glacier mass balance at Cordilleras Blanca and Huaytapallana, Peruvian Andes
Published: 2020-12-23
Subjects: Glaciology
The glaciers of the tropical Andes have been observed to be losing mass for much of the last century. These changes are both driven by, and an indicator of global climate change. These glaciers are important as they represent a crucial water source for downstream communities, supplying agriculture, urban usage, industry, mining and hydropower. This study aims to quantify glacial mass loss for the [...]
An imbalancing act: the dynamic response of the Kaskawulsh Glacier to a changing mass budget
Published: 2020-08-03
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
The Kaskawulsh Glacier is an iconic outlet draining the icefields of the St. Elias Mountains in Yukon, Canada. We determine and attempt to interpret its catchment-wide mass budget since 2007. Using SPOT5/6/7 data we estimate a 2007-2018 geodetic balance of $-$0.46 $\pm$ 0.17 m w.e. a$^{-1}$. By comparing computed balance fluxes with observed ice fluxes at nine flux gates we examine the [...]
Observing traveling waves in glaciers with remote sensing: New flexible time series methods and application to Sermeq Kujalleq (Jakobshavn Isbræ), Greenland
Published: 2020-07-22
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
The recent influx of remote sensing data provides new opportunities for quantifying spatiotemporal variations in glacier surface velocity and elevation fields. Here, we introduce a flexible time series reconstruction and decomposition technique for forming continuous, time-dependent surface velocity and elevation fields from discontinuous data and partitioning these time series into short- and [...]
Tidal Modulation of Antarctic Ice Shelf Melting
Published: 2020-07-01
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Tides influence basal melting of individual Antarctic ice shelves, but their net impact on Antarctic-wide ice-ocean interaction has yet to be constrained. Here we quantify the impact of tides on ice shelf melting and the continental shelf seas by means of a 4 km resolution circum-Antarctic ocean model. Activating tides in the model increases the total basal mass loss by 57 Gt/yr (4 %), while [...]
Antarctic Ice Shelves Lose Most of Their Mass From Shallow Depths
Published: 2020-06-18
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Understanding the processes involved in basal melting of Antarctic ice shelves is important to quantify the rate at which Antarctica will lose mass. Current research of of ice shelf-ocean interaction is almost exclusively guided by satellite derived estimates of Antarctic-wide ice shelf melting, which highlight deep warm water intrusions and melting along ice shelf grounding lines. Here we [...]
A First Constraint on Basal Melt-water Production of the Greenland Ice Sheet
Published: 2020-06-18
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
The Greenland ice sheet is one of the largest sources of sea-level rise since the early 2000s. Basal melt has not been included explicitly in assessments of ice-sheet mass loss so far. Here, we present the first full-coverage estimate of the ice-sheet wide basal melt in Greenland and its recent change through time. We find that presently basal melting contributes at least 22.3 +5/-3 Gt per year [...]
Cryoegg: development and field trials of a wireless subglacial probe for deep, fast-moving ice
Published: 2020-06-12
Subjects: Earth Sciences, Electrical and Computer Engineering, Engineering, Glaciology, Physical Sciences and Mathematics, Systems and Communications
Subglacial hydrological systems require innovative technological solutions to access and observe. Wireless sensor platforms can be used to collect and return data, but their performance in deep and fast-moving ice requires quantification. We report experimental results from Cryoegg: a spherical probe that can be deployed into a borehole or moulin and transit through the subglacial hydrological [...]