USAP-DC

Ice shelves slow the movement of the grounded ice sheets that feed them. This reduces the rate at which ice sheets lose mass to the oceans and contribute to sea-level rise. But ice shelves can be susceptible to collapse, particularly when surface meltwater accumulates in vulnerable areas. Meltwater lakes can create and enlarge fractures within the ice shelves, thereby triggering or hastening ice-shelf collapse. Also, water refreezing within ice shelves warms the ice and could affect the flow of the ice by changing its viscosity, which depends on temperature. The drainage of water across the surface of Antarctica and where it accumulates has received little attention. This drainage was assumed to be insignificant, but recent work shows that meltwater can drain for tens of kilometers across ice-shelf surfaces and access areas that would otherwise not accumulate meltwater. Surface meltwater drainage could play a major role in the future stability of ice sheets. This drainage is the focus of this project. The team will develop and test physics-based mathematical models of water flow and ice-shelf flow, closely informed by remote sensing observations, to ask (1) how drainage systems will grow in response to the increased melt rates that are predicted for this century, (2) how this drainage is influenced by ice dynamics and (3) whether enlarged drainage systems could deliver meltwater to areas of ice shelves that are vulnerable to water-driven collapse. The team hypothesizes that refreezing of meltwater in snow and firn will prove important for hydrology by impacting the permeability of the snow/firn and for ice-shelf dynamics by releasing latent heat within the ice and lowering ice viscosity. The project will examine these issues by (1) conducting a remote sensing survey of the structure and temporal evolution of meltwater systems around Antarctica, (2) developing and analyzing mathematical models of water flow across ice shelves, and (3) examining idealized and realistic models of ice-shelf flow. This project will support a first-time NSF PI, a post-doctoral researcher and a graduate student. An outreach activity will make use of the emerging technology of Augmented Reality to visualize the dynamics of ice sheets in three dimensions to excite the public about glaciology at outreach events around New York City. This approach will be made publicly available for wider use as Augmented Reality continues to grow in popularity. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

Person	Role
Kingslake, Jonathan	Investigator and contact
Lai, Ching-Yao	Researcher

Antarctic Glaciology

Award # 1743310

USAP-1743310_1

Data_managment_Kingslake.docx

Repository	Title (link)	Format(s)	Status
USAP-DC	Vulnerability of Antarctica’s ice shelves to meltwater-driven fracture	Not Provided	exists

1. Boghosian, A. L., Pratt, M. J., Becker, M. K., Cordero, S. I., Dhakal, T., Kingslake, J., … Bell, R. E. (2019). Inside the ice shelf: using augmented reality to visualise 3D lidar and radar data of Antarctica. The Photogrammetric Record, 34(168), 346–364. (doi:10.1111/phor.12298)
2. Spergel, J., Kingslake, J., Creyts, T., Van Wessem, M., & Fricker, H. (2021). Surface meltwater drainage and ponding on Amery Ice Shelf, East Antarctica, 1973–2019. Journal of Glaciology, 1-14. (doi:10.1017/jog.2021.46)
3. Fricker, H.A., Arndt, P., Brunt, K.M., Datta, R.T., Fair, Z., Jasinski, M.F., Kingslake, J., Magruder, L.A., Moussavi, M., Pope, A. and Spergel, J.J., 2021. ICESat‐2 Meltwater Depth Estimates: Application to Surface Melt on Amery Ice Shelf, East Antarctica. Geophysical Research Letters, 48(8), p.e2020GL090550. (doi:10.1029/2020GL090550)
4. Wearing, M., Kingslake, J., & Worster, M. (2020). Can unconfined ice shelves provide buttressing via hoop stresses? Journal of Glaciology, 66(257), 349-361. (doi:10.1017/jog.2019.101)
5. C. Y. Lai, J. Kingslake, M. Wearing, P.-H. Cameron Chen, P. Gentine, H. Li, J. Spergel, J. M. van Wessem, “Vulnerability of Antarctica’s ice shelves to meltwater-driven fracture," Nature, 584, 574–578 (2020). (doi:10.1038/s41586-020-2627-8)
6. Warner, R. C., Fricker, H. A., Adusumilli, S., Arndt, P., Kingslake, J., & Spergel, J. J. (2021). Rapid Formation of an Ice Doline on Amery Ice Shelf, East Antarctica. Geophysical Research Letters, 48(14). (doi:10.1029/2020gl091095)
7. Jenson, A. J., Amundson, J. M., Kingslake, J., & Hood, E. (2021). Long-period variability in ice-dammed glacier outburst floods due to evolving catchment geometry. (doi:10.5194/tc-2021-141)
8. Warner, R. C., Fricker, H. A., Adusumilli, S., Arndt, P. S., Kingslake, J., & Spergel, J. J. (2020). Rapid formation of an ice doline on Amery Ice Shelf, East Antarctica. (doi:10.1002/essoar.10504539.1)
9. Wearing, M. G., Stevens, L. A., Dutrieux, P., & Kingslake, J. (2021). Ice‐Shelf Basal Melt Channels Stabilized by Secondary Flow. Geophysical Research Letters, 48(21). (doi:10.1029/2021gl094872)