Bering Glacier and Bagley Ice Valley surge 2011: crevasse classification as an approach to map deformation stages and surge progression

Herzfeld, U. C.; McDonald, Brian; Weltman, A.

doi:10.3189/2013aog63a338

Cited by 13 publications

(25 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The 2011-2013 surge in the Bering Bagley Glacier System (BBGS), Alaska, has provided an opportunity for data collection and analysis of the surge phenomenon in a large and complex glacier system (Herzfeld, McDonald, Stachura, et al, 2013;Herzfeld, McDonald, & Weltman, 2013;Trantow & Herzfeld, 2016). The BBGS is one of the largest glacial systems outside of Greenland and Antarctica and the largest temperate surge-type glacier on Earth (Molnia, 2008).…”

Section: Introductionmentioning

confidence: 99%

Crevasses as Indicators of Surge Dynamics in the Bering Bagley Glacier System, Alaska: Numerical Experiments and Comparison to Image Data Analysis

Trantow

Herzfeld

2018

JGR Earth Surface

Self Cite

View full text Add to dashboard Cite

One of the largest sources of uncertainty in sea level rise prediction is glacial acceleration, of which the surge phenomenon is the least understood type. The surge of the Bering Bagley Glacier System (BBGS), Alaska, in 2011–2013 has provided a rare opportunity to study the surge phenomenon in a large and complex glacier system. A surge results in widespread crevassing throughout the glacier system complicating many traditional techniques used to study glacier dynamics. In this paper, we utilize crevassing as a means to investigate the recent BBGS surge through numerical modeling and geostatistical data analysis. Following the principles of structural glaciology, image‐based crevasse characterizations are obtained through geostatistical methods applied to Landsat‐7 data, supplemented by airborne field observations. On the modeling side, a 3‐D full‐Stokes finite element model of the BBGS is developed and applied to investigate ice dynamics and surface structures during the recent surge. A von Mises criterion is adopted to simulate crevassing at the glacier surface, oriented along the axes of maximum principal tensile stress. To facilitate evaluation of model‐ and data‐derived crevasse characteristics, three different comparison methods are introduced. General agreement in the model‐data comparisons indicates that the model has the ability to represent the BBGS system during peak acceleration. The crevasse‐based approach is also employed to optimize the basal sliding parameter and the von Mises stress threshold in the model. Results further indicate that bed topography is an important constraint in modeling the surge process.

show abstract

Section: Introductionmentioning

confidence: 99%

Crevasses as Indicators of Surge Dynamics in the Bering Bagley Glacier System, Alaska: Numerical Experiments and Comparison to Image Data Analysis

Trantow

Herzfeld

2018

JGR Earth Surface

Self Cite

View full text Add to dashboard Cite

show abstract

“…Crevasse geometries are classified in a scheme that emphasizes what they reveal about principal stress orientations. Next, structural provinces (Jackson and Kamb, 1997; Herzfeld and others, 2013) within the ice shelf are classified according to pervasive crevasse patterns within regions. Comparison with remotely sensed, present-day strain rates, principal stresses, and ice thickness allow us to discuss ways in which structural provinces may be used to learn about both past and present conditions on the ice shelf.…”

Section: Introductionmentioning

confidence: 99%

Structural provinces of the Ross Ice Shelf, Antarctica

et al. 2017

View full text Add to dashboard Cite

ABSTRACT. The surface of the Ross Ice Shelf (RIS) is textured by flow stripes, crevasses and other features related to ice flow and deformation. Here, moderate resolution optical satellite images are used to map and classify regions of the RIS characterized by different surface textures. Because the textures arise from ice deformation, the map is used to identify structural provinces with common deformation history. We classify four province types: regions associated with large outlet glaciers, shear zones, extension downstream of obstacles and suture zones between provinces with different upstream sources. Adjacent provinces with contrasting histories are in some locations deforming at different rates, suggesting that our province map is also an ice fabric map. Structural provinces have more complicated shapes in the part of the ice shelf fed by West Antarctic ice streams than in the part fed by outlet glaciers from the Transantarctic Mountains. The map may be used to infer past variations in stress conditions and flow events that cannot be inferred from flow traces alone.

show abstract

“…The situation would be similar to that of a surge-type glacier, where a bulge forms and the hydrologic system is obstructed (Kamb, 1987; Herzfeld and others, 2013a). Changes in the crevasse provinces would ensue, due to compressional forces during bulge formation and extensional forces during collapse (Herzfeld and others, 2013b). We do not see any changes in the crevasse provinces, as indicated by overall roughness.…”

Section: Summary Of Results and Interpretation: Attribution Of Changementioning

confidence: 99%

Elevation changes and dynamic provinces of Jakobshavn Isbræ, Greenland, derived using generalized spatial surface roughness from ICESat GLAS and ATM data

Herzfeld¹,

McDonald²,

Wallin³

et al. 2014

J. Glaciol.

Self Cite

View full text Add to dashboard Cite

ABSTRACT. Our objective is to map dynamic provinces and investigate dynamic changes in Jakobshavn Isbrae, Greenland. We use an approach that combines structural glaciology and remote-sensing data analysis, facilitated by mathematical characterization of generalized spatial surface roughness that provides parameters related to ice dynamics, deformation and interaction of the ice with bed topography. The approach is applied to derive time series of elevation and roughness changes and to attribute changes during rapid retreat.

show abstract

Bering Glacier and Bagley Ice Valley surge 2011: crevasse classification as an approach to map deformation stages and surge progression

Cited by 13 publications

References 55 publications

Crevasses as Indicators of Surge Dynamics in the Bering Bagley Glacier System, Alaska: Numerical Experiments and Comparison to Image Data Analysis

Crevasses as Indicators of Surge Dynamics in the Bering Bagley Glacier System, Alaska: Numerical Experiments and Comparison to Image Data Analysis

Structural provinces of the Ross Ice Shelf, Antarctica

Elevation changes and dynamic provinces of Jakobshavn Isbræ, Greenland, derived using generalized spatial surface roughness from ICESat GLAS and ATM data

Contact Info

Product

Resources

About