A5043339116- Cryospheric studies and observations
- Winter Sports Injuries and Performance
- Landslides and related hazards
- Geology and Paleoclimatology Research
- Arctic and Antarctic ice dynamics
- Geophysics and Gravity Measurements
- Methane Hydrates and Related Phenomena
- Granular flow and fluidized beds
- High-pressure geophysics and materials
- Polar Research and Ecology
- Climate change and permafrost
- earthquake and tectonic studies
- Archaeology and ancient environmental studies
- Tree-ring climate responses
- Marine and environmental studies
- GNSS positioning and interference
- Hydrology and Watershed Management Studies
- Geological and Geophysical Studies
- Geological and Geochemical Analysis
- Geophysical and Geoelectrical Methods
- Mineral Processing and Grinding
- Planetary Science and Exploration
- Particle Dynamics in Fluid Flows
- Quantum, superfluid, helium dynamics
- Science, Research, and Medicine
University of Michigan
2019-2024
Michigan United
2023
Cornell University
2018-2019
Wesleyan University
2008-2013
The largest uncertainty in future sea-level rise is loss of ice from the Greenland and Antarctic Ice Sheets. shelves, freely floating platforms that fringe sheets, play a crucial role restraining discharge grounded into ocean through buttressing. However, since 1990s, several shelves have thinned, retreated, collapsed. If this pattern continues, it could expose thick cliffs become structurally unstable collapse process called marine cliff instability (MICI). feedbacks between calving,...
The ocean load in glacial isostatic adjustment (GIA) modelling is represented by the so-called sea level equation (SLE). SLE describes 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 numerical solvers through which methods may be validated. goal this paper to present series synthetic examples designed for testing comparing implementations GIA modelling....
Abstract The ice sheets of the Amundsen Sea Embayment (ASE) are vulnerable to marine sheet instability (MISI), which could cause irreversible collapse and raise sea levels by over a meter. uncertain timing scale this depend on complex interaction between ice, ocean, bedrock dynamics. mantle beneath ASE is likely less viscous (∼10 18 Pa s) than Earth's average 21 s). Here we show that an effective equilibrium Pine Island Glacier's retreat response weak viscoelastic can reduce mass lost almost...
Viscoelastic rebound of the solid Earth upon removal ice loads has potential to inhibit marine sheet instability, thereby forestalling ice-sheet retreat and global mean sea-level rise. The timescale over which - system responds changes in thickness bedrock topography places a strong control on spatiotemporal influence this negative feedback mechanism. In study, we assess impact solid-earth rheological structure model projections Thwaites Glacier, West Antarctica, concomitant rise by coupling...
Abstract Inaccurate representations of iceberg calving from ice shelves are a large source uncertainty in mass-loss projections the Antarctic sheet. Here, we address this limitation by implementing and testing continuum damage-mechanics model continental scale ice-sheet model. The formulation, based on linear stability analysis subsequent long-wavelength approximation crevasses that evolve viscous medium, links damage evolution to climate forcing large-scale stresses within an shelf. We...
Abstract Rift propagation, rather than basal melt, drives the destabilization and disintegration of Thwaites Eastern Ice Shelf. Since 2016, rifts have episodically advanced throughout central ice-shelf area, with rapid propagation events occurring during austral spring. The ice shelf's speed has increased by ~70% this period, transitioning from a rate 1.65 m d −1 in 2019 to 2.85 early 2023 area. increase longitudinal strain rates near grounding zone led full-thickness melange-filled gaps...
We study shock wave formation and propagation in an experimental vertically driven quasi-two-dimensional granular gas. measure the moments of single particle velocity distribution as a function space time. The space-time fields show acoustic waves with serrated substructure on scale diameter. that this is result collisional transport which sequential collisions each momentum energy by one
Abstract The hypothesis that ice-sheet evolution is only controlled by the long-term non-Newtonian viscous behavior of ice has been challenged observations indicating effects like brittle failure, stick-slip sliding, tides and wave action may affect on sub-daily timescales. Over these timescales, quasi-static-creep approximation no longer appropriate elastic become important. Simulating in models over relevant however, remains challenging. Here, we show including a visco-elastic rheology...
Abstract Elastic deformation of the solid Earth in response to ice mass loss offers a promising constraint on density glacial material lost. Further, elastic modern deglaciation is important constrain for studies isostatic adjustment determine mantle's structure and rheology. Models this uplift are commonly based 1‐D, seismically derived global average Preliminary Reference Model typically neglect uncertainties that can arise from regional differences average, lateral heterogeneities within...
SUMMARY The viscoelastic load Love numbers encapsulate the Earth’s rheology in a remarkably efficient fashion. When multiplied by sudden increment of spherical harmonic change, they give horizontal and vertical surface displacements gravity change at all later times. Incremental glacial changes thus need only be harmonically decomposed, summed to predict response redistributions. computation from elastic, viscous adiabatic profiles Earth is foundation upon which many isostatic adjustment...
ABSTRACT The ice load configuration of the Barents Sea Ice Sheet (BSIS) over last glacial cycle is in dispute. traditional reconstruction, motivated by observation that paleo‐shoreline emergence increases towards center Sea, places a single dome at Last Glacial Maximum (LGM) collapses to island‐centered loads during deglaciation. Observations suggest flowed from islands into even LGM motivate another reconstruction with minimal marine ice. We analyze an ensemble are consistent geophysical...
A freely cooling granular gas in a gravitational field undergoes collapse to multicontact state finite time. Previous theoretical [D. Volfson et al., Phys. Rev. E 73, 061305 (2006)] and experimental work [R. Son 78, 041302 (2008)] have obtained contradictory results about the rate of energy loss before collapse. Here we use molecular dynamics simulation an attempt recreate resolve discrepancy. We are able nearly match results, find that reproduce power law predicted theory need elastic...
The Thwaites Eastern Ice Shelf stands as the last remaining floating extent of consequential Glacier in West Antarctica. In past, it has provided buttressing grounded glacier ice, but decade ice shelf undergone significant weakening that reduced its ability to buttress glacier. Important signs include: 1) flow measured by ground-based GPS shows continuous acceleration, nearly doubling speed from 1.65 m/d 2019 2.85 early 2023; 2) a recent breakout sea accelerated retreat at western calving...
Ice is a non-Newtonian fluid whose rheology typically described using Glen's flow law, power-law relationship between stress and strain rate with exponent, n, generally taken to be 3. Recent observation-based work suggests that more accurate choice for the Glen’s law exponent in high-strain regions like ice shelves may n=4, implying viscosity sensitive changes than assumed. The implications of higher sheet models their projections response climate forcing are unclear likely...