Filtering by Subject: Glaciology

Water acceleration in a supraglacial channel predicts locations of step-pool sequence formation

Andreas Alexander, Jeffrey A. Tuhtan, Maarja Kruusmaa, Thomas Vikhamar Schuler, Andreas Kääb

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

Meghana Ranganathan, Brent Minchew, Colin R. Meyer, Matej Pec

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

Gregory E Tucker, Eric Hutton, Mark Piper, Benjamin Campforts, Tian Gan, Katherine R Barnhart, Albert Kettner, Irina Overeem, Scott D Peckham, Lynn McCready, Jaia Syvitski

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

Or M. Bialik, Emilia Jarochowska, Michal Grossowicz

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

David Clark, Nicholas Barrand

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

Erik Matthew Young, Gwenn Elizabeth Flowers, Etienne Berthier, Rebecca Latto

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

Bryan Valmonte Riel, Brent Minchew, Ian Joughin

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

Ole Richter, David Gwyther, Matt King, Benjamin K. Galton-Fenzi

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

Ole Richter, Benjamin K. Galton-Fenzi, David Gwyther, Kaitlin Naughten, Matt King

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

Nanna B Karlsson, Anne M. Solgaard, Kenneth D. Mankoff, Jason E Box, Michele Citterio, William T. Colgan, Signe H. Larsen, Kristian K. Kjeldsen, Niels J. Korsgaard, Douglas I. Benn

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

Michael Robert Prior-Jones, Elizabeth Bagshaw, Jonathan Lees, Lindsay Clare, Stephen Burrow, Mauro A Werder, Nanna B Karlsson, Dorthe Dahl-Jensen, Thomas R Chudley, Poul Christoffersen

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 [...]

Rock glaciers represent hidden water stores in the Himalaya

Darren B. Jones, Karen Anderson, Sarah Shannon, Richard Betts, Stephan Harrison

Published: 2020-05-06
Subjects: Earth Sciences, Geomorphology, Glaciology, Hydrology, Physical Sciences and Mathematics

In High Mountain Asia (HMA), ongoing glacier retreat affects human and ecological systems through reduced water availability. Rock glaciers are climatically more resilient than glaciers and likely contain potentially valuable water volume equivalents (WVEQ). In HMA knowledge of rock glaciers is extremely sparse and here we present the first systematic assessment of rock glaciers for the Himalaya, [...]

The tipping points and early-warning indicators for Pine Island Glacier, West Antarctica

Sebastian Rosier, Ronja Reese, Jonathan Donges, Jan De Rydt, G. Hilmar Gudmundsson, Ricarda Winkelmann

Published: 2020-04-15
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics

Mass loss from the Antarctic Ice Sheet is the main source of uncertainty in projections of future sea-level rise, with important implications for coastal regions worldwide. Central to this is the marine ice sheet instability: once a critical threshold, or tipping point, is crossed, ice-internal dynamics can drive a self-amplifying retreat committing a glacier to irreversible, rapid and [...]

Interferometric Processing of ScanSAR Data Using Stripmap Processor: New Insights from Coregistration

Cunren Liang, Eric Jameson Fielding

Published: 2020-04-14
Subjects: Aerospace Engineering, Civil and Environmental Engineering, Computer Engineering, Earth Sciences, Electrical and Computer Engineering, Engineering, Geology, Geophysics and Seismology, Glaciology, Hydrology, Mining Engineering, Other Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure, Volcanology

Processing scanning synthetic aperture radar (ScanSAR) data using a stripmap processor, which is called full-aperture processing, has been the choice of many researchers. ScanSAR data are known to require very high azimuth coregistration precision which is usually achieved by a geometrical coregistration followed by a spectral diversity coregistration on the ScanSAR burst. However, for [...]

Interferometry with ALOS-2 full-aperture ScanSAR data

Cunren Liang, Eric Jameson Fielding

Published: 2020-04-14
Subjects: Aerospace Engineering, Civil and Environmental Engineering, Earth Sciences, Electrical and Computer Engineering, Engineering, Geology, Geophysics and Seismology, Glaciology, Mining Engineering, Other Engineering, Physical Sciences and Mathematics, Physics, Tectonics and Structure, Volcanology

Advanced Land Observing Satellite-2 (ALOS-2) is designed to routinely acquire both scanning synthetic aperture radar (ScanSAR) and stripmap data. In this paper, we present a special multiband bandpass filter (MBF) to remove azimuth nonoverlap spectra for the interferometric processing of ALOS-2 full-aperture ScanSAR product. As required by the MBF, we estimate the important ScanSAR system [...]


You can search by:

  • Title
  • Keywords
  • Author Name
  • Author Affiliation