| layout | title | permalink |
|---|---|---|
default |
CV |
/cv/ |
| Sep 2011 - August 2018 |
Ph.D. in Physics
Cornell University |
| Sep 2011 - Aug 2014 |
M.S. in Physics
Cornell University |
| Oct 2010 - May 2011 |
M.A.St., in Applied Mathematics and Theoretical Physics
Cambridge University, St. Edmund's College |
| Sep 2006 - June 2010 |
B.A. in Physics and Mathematical Economics
Wesleyan University |
| W2021 | Ice and the Climate (UM CLaSP 474), Instructional Support |
| F2020 | Earth Systems Modeling (UM CLaSP 410), Instructional Support |
| F2019 | Earth Systems Modeling (UM CLaSP 410), Instructor |
| S2012 - S2018 | Private Tutor (PHYS 2207, 2208, 1112, 2213, 2216; MAE 3780; CEE 3310), |
| S2017 | Analytical Mechanics (CU PHYS 3318), GTA |
| F2011, S2012, Su2012 | Physics II: Electromagnetism (CU PHYS 2213), GTA |
| F2012 | Physics I: Mechanics and Heat (CU PHYS 1112), GTA |
| S2010 | Quantum Mechanics I (W PHYS 214), UTA |
| F2009 | Mathematical Economics (W ECON 380), UTA |
| S2009 | General Physics II (W PHYS 116), UTA |
| F2008 | General Physics I (W PHYS 113), UTA |
| July 2018 - present |
University of Michigan, Prof. Jeremy Bassis Ice Sheet Dynamics |
| May 2012 - May 2018 |
Cornell University, Prof. Lawrence M. Cathles, III Glacial Isostatic Modeling and Analysis |
| Sep 2011 - May 2012 |
Cornell University, Prof. Itai Cohen Insect Flight Stability and Control |
| Oct 2010 - May 2011 |
GK Batchelor Fluids Laboratory, Dr. Stuart B. Dalziel Buoyancy in Permeable Media |
| Aug 2008 - June 2010 |
Wesleyan University, Prof. Greg A. Voth Granular Gas Dynamics |
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Stabilizing effect of bedrock uplift on retreat of Thwaites Glacier, Antarctica, at centennial timescales C. Book, M. Hoffman, S. Kachuck, T. Hillebrand, S. Price, M. Perego, J. Bassis Earth and Planetary Science Letters 2022 [1] [abs]
Viscoelastic rebound of the solid Earth upon the removal of ice loads has the potential to inhibit marine ice sheet instability, thereby forestalling ice-sheet retreat and global mean sea-level rise. The timescale over which the solid Earth - ice sheet system responds to changes in ice thickness and bedrock topography places a strong control on the spatiotemporal influence of this negative feedback mechanism. In this study, we assess the impact of solid-earth rheological structure on model projections of the retreat of Thwaites Glacier, West Antarctica, and the concomitant sea-level rise by coupling the dynamic ice sheet model MALI to a regional glacial isostatic adjustment (GIA) model. We test the sensitivity of model projections of ice-sheet retreat and associated sea-level rise across a range of four different solid-earth rheologies, forced by standard ISMIP6 ocean and atmospheric datasets for the RCP8.5 climate scenario. These model parameters are applied to 500-year, coupled ice-sheet - GIA simulations. For the mantle viscosity best supported by observations, the negative GIA feedback leads to a reduction in mass loss that remains above 20% after about a hundred years. Mass-loss reduction peaks at 50% around 2300, which is when a control simulation without GIA experiences its maximum rate of retreat. For a weaker solid-earth rheology that is unlikely but compatible with observational uncertainty, mass loss reduction remains above 50% after 2150. At 2100, mass loss reduction is 10% for the best-fit rheology and 25% for the weakest rheology. At the same time, we estimate that water expulsion from the rebounding solid Earth beneath the ocean near Thwaites Glacier may increase sea-level rise by up to 20% at five centuries. Additionally, the reduction in ice-sheet retreat caused by GIA is substantially reduced under stronger climate forcings, suggesting that the stabilizing feedback of GIA will also be an indirect function of emissions scenario. We hypothesize that feedbacks between the solid Earth - ice sheet system are controlled by a competition between the spatial extent and timescale of bedrock uplift relative to the rate of grounded ice retreat away from the region of most rapid unloading. Although uncertainty in solid-earth rheology leads to large uncertainty in future sea-level rise contribution from Thwaites Glacier, under all plausible parameters the GIA effects are too large to be ignored for future projections of Thwaites Glacier of more than a century.
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Simulating ice-shelf extent using damage mechanics S. Kachuck, M. Whitcomb, J. Bassis, D. Martin, and S. Price Journal of Glaciology 2022 [1] [abs]
Inaccurate representations of iceberg calving from ice shelves are a large source of uncertainty in mass-loss projections from the Antarctic ice sheet. Here, we address this limitation by implementing and testing a continuum damage-mechanics model in a continental scale ice-sheet model. The damage-mechanics formulation, based on a linear stability analysis and subsequent long-wavelength approximation of crevasses that evolve in a viscous medium, links damage evolution to climate forcing and the large-scale stresses within an ice shelf. We incorporate this model into the BISICLES ice-sheet model and test it by applying it to idealized (1) ice tongues, for which we present analytical solutions and (2) buttressed ice-shelf geometries. Our simulations show that the model reproduces the large disparity in lengths of ice shelves with geometries and melt rates broadly similar to those of four Antarctic ice shelves: Erebus Glacier Tongue (length ~ 13 km), the unembayed portion of Drygalski Ice Tongue (~ 65 km), the Amery Ice Shelf (~ 350 km) and the Ross Ice Shelf (~ 500 km). These results demonstrate that our simple continuum model holds promise for constraining realistic ice-shelf extents in large-scale ice-sheet models in a computationally tractable manner.
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Rapid viscoelastic deformation slows marine ice sheet instability at Pine Island Glacier S. Kachuck, D. Martin, J. Bassis, and S. Price GRL 2020 [1] [abs]
The ice sheets of the Amundsen Sea Embayment (ASE) are vulnerable to the marine ice sheet instability (MISI), which could cause irreversible collapse and raise sea levels by over a meter. The uncertain timing and scale of this collapse depend on the complex interaction between ice, ocean, and bedrock dynamics. The mantle beneath the ASE is likely less viscous (~1018 Pa s) than the Earth's average mantle (~1021 Pa s). Here we show that an effective equilibrium between Pine Island Glacier's retreat and the response of a weak viscoelastic mantle can reduce ice mass lost by almost 30 per cent over 150 years. Other components of solid Earth response—purely elastic deformations and geoid perturbations—provide less stability than the viscoelastic response alone. Uncertainties in mantle rheology, topography, and basal melt affect how much stability we expect, if any. Our study indicates the importance of considering viscoelastic uplift during the rapid retreat associated with MISI.
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Benchmarked computation of time-domain viscoelastic Love numbers for adiabatic mantles S. Kachuck and L. Cathles GJI 2019 [2] [abs]
The viscoelastic load Love numbers encapsulate the Earth’s rheology in a remarkably efficient fashion. When multiplied by a sudden increment of spherical harmonic load change, they give the horizontal and vertical surface displacements and gravity change at all later times. Incremental glacial load changes thus need only be harmonically decomposed, multiplied by the Love numbers and summed to predict the Earth’s response to glacial load redistributions. The computation of viscoelastic Love numbers from the elastic, viscous and adiabatic profiles of the Earth is thus the foundation upon which many glacial isostatic adjustment models are based. Usually, viscoelastic Love numbers are computed using the Laplace transform method, employing the correspondence principle to convert the viscoelastic equations of motion into the elastic equations with complex material parameters. This method works well for a fully non-adiabatic Earth, but can accommodate realistic partially adiabatic and fully adiabatic conditions only by changing the Earth’s density profile. An alternative method of Love number computation developed by Cathles (1975) avoids this dilemma by separating the elastic and viscous equations of motion. The separation neglects a small solid-elastic/fluid-elastic transition for compressible deformation, but allows freely defining adiabatic, partially adiabatic or fully non-adiabatic profiles in the mantle without changing the Earth’s density profile. Here, we update and fully describe this method and show that it produces Love numbers closely similar to those computed for fully non-adiabatic earth models computed by the correspondence principle, finite element and other methods. The time-domain method produces Love numbers as good as those produced by other methods and can also realistically accommodate any degree of mantle adiabaticity. All method implementations are available open source.
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The Importance of the Inelastic and Elastic Structures of the Crust in Constraining Glacial Density, Mass Change, and Isostatic Adjustment From Geodetic Observations in Southeast Alaska W. Durkin, S. Kachuck, and M. Pritchard JGR: Solid Earth 2019 [3] [abs]
Elastic deformation of the solid Earth in response to ice mass loss offers a promising constraint on the density of glacial material lost. Further, the elastic response to modern deglaciation is important to constrain for studies of glacial isostatic adjustment to determine the mantle's structure and rheology. Models of this elastic uplift are commonly based on the 1-D, seismically derived global average Preliminary Reference Earth Model and typically neglect uncertainties that can arise from regional differences in elastic structure from that of the global average, lateral heterogeneities within the region, and inelastic behavior of the crust. We quantify these uncertainties using an ensemble of 1-D local elastic structure models and empirical relations for the effects of inelasticity in the upper 10 km of the crust. In Southeast Alaska, modeling elastic uplift rates with local elastic structures results in up to a 20–40 percent difference from those modeled with the Preliminary Reference Earth Model. Although these differences are limited to regions near to ice-covered areas, they are comparable to the differences in uplift rates expected from the loss of firn versus loss of ice. Far from ice-covered areas, where most of the region's GPS observations were made, these differences become insignificant and do not affect previous glacial isostatic adjustment studies in the region. The methods presented here are based on the globally available LITHO1.0 seismic model and open source software, and the approach of using an ensemble of 1-D elastic structures can be easily adapted to other regions around the world.
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A benchmark study of numerical implementations of the sea level equation in GIA modelling Z. Martinec, V. Klemann, W. der Wal, R. Riva, G. Spada, Y. Sun, D. Melini, S. Kachuck, V. Barletta, K. Simon, G. A, and T. James GJI 2018 [4] [abs]
The ocean load in glacial isostatic adjustment (GIA) modelling is represented by the so-called sea level equation (SLE). The SLE describes the mass redistribution of water between ice sheets and oceans on a deforming Earth. Despite various teams independently investigating GIA, there has been no systematic intercomparison among the numerical solvers of the SLE through which the methods may be validated. The goal of this paper is to present a series of synthetic examples designed for testing and comparing the numerical implementations of the SLE in GIA modelling. The 10 numerical codes tested combine various temporal and spatial parametrizations. The time-domain or Laplace-domain discretizations are used to solve the SLE through time, while spherical harmonics, finite differences or finite elements parametrize the GIA-related field variables spatially. The surface ice-water load and solid Earth’s topography are represented spatially either on an equiangular grid, a Gauss–Legendre or an equiarea grid with icosahedron-shaped spherical pixels. Comparisons are made in a series of five benchmark examples with an increasing degree of complexity. Due to the complexity of the SLE, there is no analytical solution to it. The accuracy of the numerical implementations is therefore assessed by the differences of the individual solutions with respect to a reference solution. While the benchmark study does not result in GIA predictions for a realistic loading scenario, we establish a set of agreed-upon results that can be extended in the future by including more complex case studies, such as solutions with realistic loading scenarios, the rotational feedback in the linear-momentum equation, and by considering a 3-D viscosity structure of the Earth’s mantle. The test computations performed so far show very good agreement between the individual results and their ability to capture the main features of sea-surface variation and the surface vertical displacement. The differences found can often be attributed to the different approximations inherent in the various algorithms. This shows the accuracy that can be expected from different implementations of the SLE, which helps to assess differences noted in the literature between predictions for realistic loading cases.
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Constraining the Geometry and Volume of the Barents Sea Ice Sheet S. Kachuck and L. Cathles JQS 2018 [5] [abs]
The ice load configuration of the Barents Sea Ice Sheet (BSIS) over the last glacial cycle is in dispute. The traditional reconstruction, motivated by the observation that paleo-shoreline emergence increases toward the center of the Barents Sea, places a single dome in the center of the Barents Sea at the last glacial maximum (LGM) that collapses to island centered loads during deglaciation. Observations that suggest that ice flowed from the islands into the Barents even at the LGM motivate another reconstruction that places the ice loads over the islands with minimal marine ice. We analyze an ensemble of ice loads that are consistent with the geophysical observations using relatively new statistical methods and show that current relative sea level, GPS and gravity measurement do not and cannot distinguish a central dome from an island-centered BSIS. What is needed are constraints in the central Barents Sea. Improving the gravity data sufficiently will be difficult. However, obtaining even a single GPS uplift rate measurement in the central Barents would resolve the central dome versus island centered BSIS geometry question. The Barents Sea ice load geometry uncertainty provides a good illustration of statistical methods that may be useful in other areas of glaciology.
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Simulations of granular gravitational collapse S. Kachuck and G. Voth PRE 2013 [6] [abs]
A freely cooling granular gas in a gravitational field undergoes a collapse to a multicontact state in a finite time. Previous theoretical [D. Volfson et al., Phys. Rev. E 73, 061305 (2006)] and experimental work [R. Son et al., Phys. Rev. E 78, 041302 (2008)] have obtained contradictory results about the rate of energy loss before the gravitational collapse. Here we use a molecular dynamics simulation in an attempt to recreate the experimental and theoretical results to resolve the discrepancy. We are able to nearly match the experimental results, and find that to reproduce the power law predicted in the theory we need a nearly elastic system with a constant coefficient of restitution greater than 0.993. For the more realistic velocity-dependent coefficient of restitution, there does not appear to be a power-law decay and the transition from granular gas to granular solid is smooth, making it difficult to define a time of collapse.
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Visualization of collisional substructure in granular shock waves J. Perez, S. Kachuck, and G. Voth PRE 2008 [7] [abs]
We study shock wave formation and propagation in an experimental vertically driven quasi-two-dimensional granular gas. We measure the moments of the single particle velocity distribution as a function of space and time. The space-time fields of the velocity moments show acoustic waves with a serrated substructure on the scale of a particle diameter. We show that this substructure is the result of collisional transport in which sequential collisions each transport momentum and energy by one particle diameter.
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| Languages: | Python, C/C++, FORTRAN, APL, LaTeX, Matlab |
| Instruments: | Piano, fiddle, guitar |
| 2018- | Peer Reviewer: JGR: Solid Earth, Solid Earth, The Cryosphere |
| 2021 | URGE (Unlearning Racism in GEosciences) Pod |
| 2020 | Internal Grant Reviewer for Los Alamos National Lab |
| 2018-2019 | AGU Fall Meeting OSPA Judge |
| 2019 | Steering Committee: International Thwaites Glacier Collaboration: Early Career Reteat |
| 2019 | Michigan Geophysical Union Symposium Judge |
| 2018 | Engineering Graduate Symposium Judge |
| 2016-2017 | Graduate Student Union Communications Committee |
| 2013 | Cornell Physics Graduate Teaching Assistant Review |
| 2012-2013 | Cornell Physics Graduate Teaching Assisant Training |
| 2016- | Letters to a Pre-Scientist |
| 2018, 2020 | Antarctic Week Guest Lecturer in Elementary Schools |
| 2020 | Waterford-Kettering High School Guest Lecture |
| 2016-2018 | Local Geology Walk |
| 2013 | Graduate Teaching Assistant Review |
| 2012, 2013 | Graduate Teaching Assistant Training |
| 2012 | Alumni Day Physics Demonstrations |
| 2011 | Retrospective Degree Day Fluids Demonstrations |
| 2021 | NERSC High Performance Computing Achievement Award |
| 2017 | Douglas A Fitchen Scholar: for international travel to present physics |
| 2016 | AGU Outstanding Student Paper Award |
| 2012 | NSF GRFP Honorable Mention |
| 2010 | Phi Beta Kappa |
| 2010 | Graham Prize: for excellence in natural science |
| 2010 | Karl van Dyke Prize: for outstanding achievement in physical science |
| 2010 | Plukas Teaching Apprentice Award: for excellent service to the Economics Department as a TA |
| 2010 | White Prize, for advanced undergraduate study in economics |
| 2006 - 2010 | Dean's List, Wesleyan University |
| 2007 | Squire Fund Fellow: for research into Classical Civilizations |
| 2007 | Chadbourne Prize: for the freshman student displaying outstanding character, conduct, and leadership |
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Geometric perspective on fitting glacial isostatic adjustment S. Kachuck in prep in prep [J1] |
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Simulating ice shelf extent using damage mechanics S. Kachuck, M. Whitcomb, J. Bassis, D. Martin, and S. Price in review in review [J2] |
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Rapid viscoelastic deformation slows marine ice sheet instability at Pine Island Glacier S. Kachuck, D. Martin, J. Bassis, and S. Price GRL 2020 [J3] [abs]
The ice sheets of the Amundsen Sea Embayment (ASE) are vulnerable to the marine ice sheet instability (MISI), which could cause irreversible collapse and raise sea levels by over a meter. The uncertain timing and scale of this collapse depend on the complex interaction between ice, ocean, and bedrock dynamics. The mantle beneath the ASE is likely less viscous (~1018 Pa s) than the Earth's average mantle (~1021 Pa s). Here we show that an effective equilibrium between Pine Island Glacier's retreat and the response of a weak viscoelastic mantle can reduce ice mass lost by almost 30 per cent over 150 years. Other components of solid Earth response—purely elastic deformations and geoid perturbations—provide less stability than the viscoelastic response alone. Uncertainties in mantle rheology, topography, and basal melt affect how much stability we expect, if any. Our study indicates the importance of considering viscoelastic uplift during the rapid retreat associated with MISI.
|
|
Benchmarked computation of time-domain viscoelastic Love numbers for adiabatic mantles S. Kachuck and L. Cathles GJI 2019 [J4] [abs]
The viscoelastic load Love numbers encapsulate the Earth’s rheology in a remarkably efficient fashion. When multiplied by a sudden increment of spherical harmonic load change, they give the horizontal and vertical surface displacements and gravity change at all later times. Incremental glacial load changes thus need only be harmonically decomposed, multiplied by the Love numbers and summed to predict the Earth’s response to glacial load redistributions. The computation of viscoelastic Love numbers from the elastic, viscous and adiabatic profiles of the Earth is thus the foundation upon which many glacial isostatic adjustment models are based. Usually, viscoelastic Love numbers are computed using the Laplace transform method, employing the correspondence principle to convert the viscoelastic equations of motion into the elastic equations with complex material parameters. This method works well for a fully non-adiabatic Earth, but can accommodate realistic partially adiabatic and fully adiabatic conditions only by changing the Earth’s density profile. An alternative method of Love number computation developed by Cathles (1975) avoids this dilemma by separating the elastic and viscous equations of motion. The separation neglects a small solid-elastic/fluid-elastic transition for compressible deformation, but allows freely defining adiabatic, partially adiabatic or fully non-adiabatic profiles in the mantle without changing the Earth’s density profile. Here, we update and fully describe this method and show that it produces Love numbers closely similar to those computed for fully non-adiabatic earth models computed by the correspondence principle, finite element and other methods. The time-domain method produces Love numbers as good as those produced by other methods and can also realistically accommodate any degree of mantle adiabaticity. All method implementations are available open source.
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The Importance of the Inelastic and Elastic Structures of the Crust in Constraining Glacial Density, Mass Change, and Isostatic Adjustment From Geodetic Observations in Southeast Alaska W. Durkin, S. Kachuck, and M. Pritchard JGR: Solid Earth 2019 [J5] [abs]
Elastic deformation of the solid Earth in response to ice mass loss offers a promising constraint on the density of glacial material lost. Further, the elastic response to modern deglaciation is important to constrain for studies of glacial isostatic adjustment to determine the mantle's structure and rheology. Models of this elastic uplift are commonly based on the 1-D, seismically derived global average Preliminary Reference Earth Model and typically neglect uncertainties that can arise from regional differences in elastic structure from that of the global average, lateral heterogeneities within the region, and inelastic behavior of the crust. We quantify these uncertainties using an ensemble of 1-D local elastic structure models and empirical relations for the effects of inelasticity in the upper 10 km of the crust. In Southeast Alaska, modeling elastic uplift rates with local elastic structures results in up to a 20–40 percent difference from those modeled with the Preliminary Reference Earth Model. Although these differences are limited to regions near to ice-covered areas, they are comparable to the differences in uplift rates expected from the loss of firn versus loss of ice. Far from ice-covered areas, where most of the region's GPS observations were made, these differences become insignificant and do not affect previous glacial isostatic adjustment studies in the region. The methods presented here are based on the globally available LITHO1.0 seismic model and open source software, and the approach of using an ensemble of 1-D elastic structures can be easily adapted to other regions around the world.
|
|
A benchmark study of numerical implementations of the sea level equation in GIA modelling Z. Martinec, V. Klemann, W. der Wal, R. Riva, G. Spada, Y. Sun, D. Melini, S. Kachuck, V. Barletta, K. Simon, G. A, and T. James GJI 2018 [J6] [abs]
The ocean load in glacial isostatic adjustment (GIA) modelling is represented by the so-called sea level equation (SLE). The SLE describes the mass redistribution of water between ice sheets and oceans on a deforming Earth. Despite various teams independently investigating GIA, there has been no systematic intercomparison among the numerical solvers of the SLE through which the methods may be validated. The goal of this paper is to present a series of synthetic examples designed for testing and comparing the numerical implementations of the SLE in GIA modelling. The 10 numerical codes tested combine various temporal and spatial parametrizations. The time-domain or Laplace-domain discretizations are used to solve the SLE through time, while spherical harmonics, finite differences or finite elements parametrize the GIA-related field variables spatially. The surface ice-water load and solid Earth’s topography are represented spatially either on an equiangular grid, a Gauss–Legendre or an equiarea grid with icosahedron-shaped spherical pixels. Comparisons are made in a series of five benchmark examples with an increasing degree of complexity. Due to the complexity of the SLE, there is no analytical solution to it. The accuracy of the numerical implementations is therefore assessed by the differences of the individual solutions with respect to a reference solution. While the benchmark study does not result in GIA predictions for a realistic loading scenario, we establish a set of agreed-upon results that can be extended in the future by including more complex case studies, such as solutions with realistic loading scenarios, the rotational feedback in the linear-momentum equation, and by considering a 3-D viscosity structure of the Earth’s mantle. The test computations performed so far show very good agreement between the individual results and their ability to capture the main features of sea-surface variation and the surface vertical displacement. The differences found can often be attributed to the different approximations inherent in the various algorithms. This shows the accuracy that can be expected from different implementations of the SLE, which helps to assess differences noted in the literature between predictions for realistic loading cases.
|
|
Constraining the Geometry and Volume of the Barents Sea Ice Sheet S. Kachuck and L. Cathles JQS 2018 [J7] [abs]
The ice load configuration of the Barents Sea Ice Sheet (BSIS) over the last glacial cycle is in dispute. The traditional reconstruction, motivated by the observation that paleo-shoreline emergence increases toward the center of the Barents Sea, places a single dome in the center of the Barents Sea at the last glacial maximum (LGM) that collapses to island centered loads during deglaciation. Observations that suggest that ice flowed from the islands into the Barents even at the LGM motivate another reconstruction that places the ice loads over the islands with minimal marine ice. We analyze an ensemble of ice loads that are consistent with the geophysical observations using relatively new statistical methods and show that current relative sea level, GPS and gravity measurement do not and cannot distinguish a central dome from an island-centered BSIS. What is needed are constraints in the central Barents Sea. Improving the gravity data sufficiently will be difficult. However, obtaining even a single GPS uplift rate measurement in the central Barents would resolve the central dome versus island centered BSIS geometry question. The Barents Sea ice load geometry uncertainty provides a good illustration of statistical methods that may be useful in other areas of glaciology.
|
|
Simulations of granular gravitational collapse S. Kachuck and G. Voth PRE 2013 [J8] [abs]
A freely cooling granular gas in a gravitational field undergoes a collapse to a multicontact state in a finite time. Previous theoretical [D. Volfson et al., Phys. Rev. E 73, 061305 (2006)] and experimental work [R. Son et al., Phys. Rev. E 78, 041302 (2008)] have obtained contradictory results about the rate of energy loss before the gravitational collapse. Here we use a molecular dynamics simulation in an attempt to recreate the experimental and theoretical results to resolve the discrepancy. We are able to nearly match the experimental results, and find that to reproduce the power law predicted in the theory we need a nearly elastic system with a constant coefficient of restitution greater than 0.993. For the more realistic velocity-dependent coefficient of restitution, there does not appear to be a power-law decay and the transition from granular gas to granular solid is smooth, making it difficult to define a time of collapse.
|
|
Visualization of collisional substructure in granular shock waves J. Perez, S. Kachuck, and G. Voth PRE 2008 [J9] [abs]
We study shock wave formation and propagation in an experimental vertically driven quasi-two-dimensional granular gas. We measure the moments of the single particle velocity distribution as a function of space and time. The space-time fields of the velocity moments show acoustic waves with a serrated substructure on the scale of a particle diameter. We show that this substructure is the result of collisional transport in which sequential collisions each transport momentum and energy by one particle diameter.
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Implementing novel physics in ice sheet models for improved sea-level projections \emph{(invited)} S. Kachuck NERSC Seminar Series 2021 [O1] |
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Damage Control: forming stable ice shelves in simulations with damage mechanics S. Kachuck, M. Whitcomb, J. Bassis, D. Martin, and P. S. WAIS 2021 [O2] |
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The ice and earth physics of sea level change S. Kachuck Wesleyan University Physics Colloquium 2021 [O3] |
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A Statistical Physics Description of Glacier Calving Behavior in Ice-Shelf Evolution P. Brady and S. Kachuck CUWiP 2021 [O4] |
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Rapid viscoelastic deformation slows marine ice sheet instability in the Amundsen Sea Embayment S. Kachuck, D. Martin, J. Bassis, and S. Price AGU 2020 [O5] |
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Sensitivity of Coupled Solid Earth - Ice Sheet MOdeling of Thwaiters Flacier to Coupling Timescale and Earth Rheology C. Book, M. Hoffman, and S. Kachuck WAIS 2020 [O6] |
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Solid Earth Feedbacks \emph{(invited)} S. Kachuck ITGC: The Next Generation 2019 [O7] |
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Politics of modeling S. Kachuck University of Michigan STS Workshop 2019 [O8] |
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Rapid viscous response slows Pine Island grounding-line retreat S. Kachuck, D. Martin, J. Bassis, and S. Price GIA Workshop, Ottawa 2019 [O9] |
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A benchmark study of numerical implementations of the sea-level equation in GIA modelling Z. Martinec, V. Klemann, .. .., and S. Kachuck EGU 2018 [O10] |
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Impact of different crustal elastic models on interpreting regional GIA deformation in southeast Alaska W. Durkin, S. Kachuck, and M. Pritchard EGU 2018 [O11] |
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Nondimensionalized relaxation method for efficient computation of elastic Love numbers S. Kachuck and L. Cathles Workshop on Glacial Isostatic Adjustment and Elastic Deformation 2017 [O12] |
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Emergence constraints on Late Weichselian Barents Sea ice sheet history S. Kachuck, L. Cathles, A. Amantov, A. Hormes, and W. Fjeldskaar EGU 2014 [O13] |
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Velocity dependent energy loss in granular gravitational collapse S. Kachuck New York Condesnsed Matter Workshop 2011 [O14] |
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Rapid viscoelastic response to ice loss in the ASE slows grounding line retreat S. Kachuck, D. Martin, J. Bassis, and S. Price ITGC: Science Meeting 2020 [P1] |
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Data and Simulacra, toward a framework for inclusive coproduction \emph{(invited)} S. Kachuck AGU 2020 [P2] |
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Rapid viscoelastic deformation slows marine ice sheet instability at Pine Island Glacier S. Kachuck, D. Martin (presenter), J. Bassis, and S. Price AGU 2019 [P3] |
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giapy: Glacial Isostatic Adjustment in PYthon: Nondimensionalized relaxation method for computation of time-domain viscoelastic Love numbers S. Kachuck and L. Cathles American Geosciences Union 2018 [P4] |
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Low visocosity mantle feedback in Amundsen Sea Embayment dynamics S. Kachuck and J. Bassis West Antarctic Ice Sheet Initiative 2018 [P5] |
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Using geometry to improve model fitting and experiment design for glacial isostasy \emph{(invited) } S. Kachuck and L. Cathles American Geosciences Union 2017 [P6] |
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Sloppy inversion and optimal experiment design for last glacial maximum Barents Sea Ice Sheet configuration S. Kachuck and L. Cathles American Geosciences Union 2016 [P7] |
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GIA response suggests thick lithosphere under the Appalachians S. Kachuck and L. Cathles Institute for the Study of the Continents 2014 [P8] |
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North American Peripheral Bulge Constraints on Mantle Rheology S. Kachuck, L. Cathles, A. Amantov, and W. Fjeldskaar European Geosciences Union 2014 [P9] |
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The SEAMOD methodology of GIA interpretation L. Cathles, A. Amantov, S. Kachuck, and W. Fjeldskaar European Geosciences Union 2014 [P10] |
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Lithosphere, Ice History, Local Emergence S. Kachuck and L. Cathles European Geosciences Union 2013 [P11] |
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Granular Gravitational Collapse in Realistically Simulated Granular Gases S. Kachuck 5th Annual Thesis Celebration 2010 [P12] |