Fluid Dynamics Course Projects

2019

Fluid Dynamics 2019 attempted a collaborative project focused on evaluating the stability of Thwaites Glacier, West Antarctica, over the next 200 years. This effort involved creating cross-informed numerical models using Smoothed Particle Hydrodynamics (SPH; 1) and the Ice Sheet System Model (ISSM; 2). The results were presented in a webinar presentation format hosted and archived by the US Association of Polar Early Career Scientists (USAPECS).

Jukes Liu used observations by Pierre Dutrieux (3) to calculate geostrophic flow near the margins of the Thwaites floating ice shelf, and input these calculations to thermodynamic equations to cross-evaluate with reported values of basal melt.

Ian Nesbitt created a coupled atmosphere ocean model in SPH, in an attempt to capture the local mixing processes that occur due to katabatic wind stress flowing off of the Thwaites ice sheet/ice shelf when there is no sea ice buffer protecting the ocean surface. Output from the SPH model was fed into a thermodynamic equation to determine melt rate potential, which was cross-checked with literature and observed melt rates, then used to parameterize basal melt on the floating ice shelf in the ISSM model.

Mariama Dryak and Clara Deck created an ISSM solution designed to evaluate the stability of the Thwaites glacier system based on anticipated and experimental changes in surface mass balance (SMB) and basal melt. Surface mass balance values were derived from anticipated snow water equivalent expected in two IPCC Representative Concentration Pathways (RCPs): RCP2.6 and RCP8.5 (4). Basal melt values were derived from: 1) geothermal heat at the base, 2) measurements of large-scale melt holes described by Milillo (2019; 5), and 3) the outputs from the SPH simulation.

Jackie Feng evaluated grounded ice rheology (6), geothermal flux (7), and basal friction (7, 8) in the ISSM model to ensure that these parameters were on par with values that other researchers had reported previously, and whether moderate changes to these values would cause changes to the stability of the system.

References

1. Crespo, A.J., Domínguez, J.M., Rogers, B.D., Gómez-Gesteira, M., Longshaw, S., Canelas, R., Vacondio, R., Barreiro, A. and García-Feal, O., 2015. DualSPHysics: Open-source parallel CFD solver based on Smoothed Particle Hydrodynamics (SPH). Computer Physics Communications, 187, pp.204-216.

2. Larour, E., Seroussi, H., Morlighem, M. and Rignot, E., 2012. Continental scale, high order, high spatial resolution, ice sheet modeling using the Ice Sheet System Model (ISSM). Journal of Geophysical Research: Earth Surface, 117(F1).

3. Dutrieux, P. Personal communication. NERC iSTAR program (UK), A. Jenkins and K. Heywood Principal Investigators.

4. IPCC, 2013: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 1535.

5. Milillo, P., Rignot, E., Rizzoli, P., Scheuchl, B., Mouginot, J., Bueso-Bello, J. and Prats-Iraola, P., 2019. Heterogeneous retreat and ice melt of Thwaites Glacier, West Antarctica. Science advances, 5(1), p.eaau3433.

6. Suckale, J., Platt, J.D., Perol, T. and Rice, J.R., 2014. Deformation‐induced melting in the margins of the West Antarctic ice streams. Journal of Geophysical Research: Earth Surface, 119(5), pp.1004-1025.

7. Joughin, I., Tulaczyk, S., Bamber, J.L., Blankenship, D., Holt, J.W., Scambos, T. and Vaughan, D.G., 2009. Basal conditions for Pine Island and Thwaites Glaciers, West Antarctica, determined using satellite and airborne data. Journal of Glaciology, 55(190), pp.245-257.

8. Morlighem, M., Seroussi, H., Larour, E. and Rignot, E., 2013. Inversion of basal friction in Antarctica using exact and incomplete adjoints of a higher‐order model. Journal of Geophysical Research: Earth Surface, 118(3), pp.1746-1753.