Open Access. Powered by Scholars. Published by Universities.®
- Discipline
Articles 1 - 6 of 6
Full-Text Articles in Glaciology
Kinematics Of The Exceptionally-Short Surge Cycles Of Sít’ Kusá (Turner Glacier), Alaska, From 1983 To 2013, Andrew Nolan, William Kochtitzky, Ellyn M. Enderlin, Robert Mcnabb, Karl J. Kreutz
Kinematics Of The Exceptionally-Short Surge Cycles Of Sít’ Kusá (Turner Glacier), Alaska, From 1983 To 2013, Andrew Nolan, William Kochtitzky, Ellyn M. Enderlin, Robert Mcnabb, Karl J. Kreutz
Geosciences Faculty Publications and Presentations
Glacier surges are periodic episodes of mass redistribution characterized by dramatic increases in ice flow velocity and, sometimes, terminus advance. We use optical satellite imagery to document five previously unexamined surge events of Sít’ Kusá (Turner Glacier) in the St. Elias Mountains of Alaska from 1983 to 2013. Surge events had an average recurrence interval of ~5 years, making it the shortest known regular recurrence interval in the world. Surge events appear to initiate in the winter, with speeds reaching up to ~25 m d−1. The surges propagate down-glacier over ~2 years, resulting in maximum thinning of ~100 …
Sharp Contrasts In Observed And Modeled Crevasse Patterns At Greenland’S Marine Terminating Glaciers, Ellyn M. Enderlin, Timothy C. Bartholomaus
Sharp Contrasts In Observed And Modeled Crevasse Patterns At Greenland’S Marine Terminating Glaciers, Ellyn M. Enderlin, Timothy C. Bartholomaus
Geosciences Faculty Publications and Presentations
Crevasses are affected by and affect both the stresses and the surface mass balance of glaciers. These effects are brought on through potentially important controls on meltwater routing, glacier viscosity, and iceberg calving, yet there are few direct observations of crevasse sizes and locations to inform our understanding of these interactions. Here we extract depth estimates for the visible portion of crevasses from high-resolution surface elevation observations for 52 644 crevasses from 19 Greenland glaciers. We then compare our observed depths with those calculated using two popular models that assume crevasse depths are functions of local stresses: the Nye and …
Evaluation Of Iceberg Calving Models Against Observations From Greenland Outlet Glaciers, Tristan Amaral, Timothy C. Bartholomaus, Ellyn M. Enderlin
Evaluation Of Iceberg Calving Models Against Observations From Greenland Outlet Glaciers, Tristan Amaral, Timothy C. Bartholomaus, Ellyn M. Enderlin
Geosciences Faculty Publications and Presentations
Frontal ablation processes at marine‐terminating glaciers are challenging to observe and difficult to represent in numerical ice flow models, yet play critical roles in modulating ice sheet mass balance. Current ice sheet models typically rely on simple iceberg calving models to prescribe either terminus positions or iceberg calving rates, but the relative accuracies and uncertainties of these calving models remain largely unconstrained at the ice sheet scale. Here, we evaluate six published iceberg calving models against spatially and temporally diverse observations from 50 marine‐terminating outlet glaciers in Greenland. We seek the single model that best reproduces observed conditions across all …
Analysis Of Antarctic Peninsula Glacier Frontal Ablation Rates With Respect To Iceberg Melt-Inferred Variability In Ocean Conditions, M. C. Dryak, E. M. Enderlin
Analysis Of Antarctic Peninsula Glacier Frontal Ablation Rates With Respect To Iceberg Melt-Inferred Variability In Ocean Conditions, M. C. Dryak, E. M. Enderlin
Geosciences Faculty Publications and Presentations
Marine-terminating glaciers on the Antarctic Peninsula (AP) have retreated, accelerated and thinned in response to climate change in recent decades. Ocean warming has been implicated as a trigger for these changes in glacier dynamics, yet little data exist near glacier termini to assess the role of ocean warming here. We use remotely-sensed iceberg melt rates seaward of two glaciers on the eastern and six glaciers on the western AP from 2013 to 2019 to explore connections between variations in ocean conditions and glacier frontal ablation. We find iceberg melt rates follow regional ocean temperature variations, with the highest melt rates …
Future Evolution Of Greenland's Marine-Terminating Outlet Glaciers, G. A. Catania, L. A. Stearns, T. A. Moon, E. M. Enderlin, R. H. Jackson
Future Evolution Of Greenland's Marine-Terminating Outlet Glaciers, G. A. Catania, L. A. Stearns, T. A. Moon, E. M. Enderlin, R. H. Jackson
Geosciences Faculty Publications and Presentations
Mass loss from the Greenland ice sheet (GrIS) has increased over the last two decades in response to changes in global climate, motivating the scientific community to question how the GrIS will contribute to sea-level rise on timescales that are relevant to coastal communities. Observations also indicate that the impact of a melting GrIS extends beyond sea-level rise, including changes to ocean properties and circulation, nutrient and sediment cycling, and ecosystem function. Unfortunately, despite the rapid growth of interest in GrIS mass loss and its impacts, we still lack the ability to confidently predict the rate of future mass loss …
Climate And Surging Of Donjek Glacier, Yukon, Canada, Ellyn M. Enderlin
Climate And Surging Of Donjek Glacier, Yukon, Canada, Ellyn M. Enderlin
Geosciences Faculty Publications and Presentations
Links between climate and glacier surges are poorly understood but are required to enable prediction of surges and mitigation of associated hazards. Here, we investigate the role of snow accumulation, rain, and temperature on surge periodicity, area changes, and timing of surge initiation since the 1930s at Donjek Glacier, Yukon, Canada. Snow accumulation measured in three ice cores collected at Eclipse Icefield indicates that a cumulative accumulation of 15.5 ± 1.46 or 16.6 ± 2.0 m w.e. occurred in the ten to twelve years between each of its last eight surges, depending on ice motion spatiotemporal offset corrections. Although we …