009-seaicemuri.txt (1996B)
1 Below is my recorded talk for an upcoming workshop on modeling the 2 granular nature of sea ice[1] The workshop is online, and will take 3 place in the week of June 7th, 2021. Full abstract: 4 5 Title: Floe-scale ridging in discrete element models for sea ice 6 7 Anders Damsgaard(1,2), Olga V. Sergienko(1), Alistair Adcroft(1) 8 9 1: Program in Atmospheric and Oceanic Sciences, Princeton University, 10 New Jersey, USA 11 12 2: Department of Geoscience, Aarhus University, Aarhus, Denmark 13 14 Ridging and rafting through compression and shear increase the 15 thickness and therefore also the melt resilience of sea-ice packs. 16 Present formulations for these mechanisms assume that ice strength is 17 solely governed by ice thickness, and generally treat the ice pack as 18 a continuum where each cell in the spatial discretization includes 19 many individual ice floes. Particle-based sea ice models with 20 granular interactions generally represent the ice on a floe-by-floe 21 basis, meaning that new formulations are required for including 22 ridging. We show through small-scale, high-resolution Discrete 23 Element Method simulations that floe-floe compression encompasses 24 different deformational modes, where elasticity transitions to 25 frictional sliding and resultant strain weakening at the onset of 26 ridging. We present a generalized formulation based on elasticity 27 and Coulomb friction which is suitable for simulating the contact 28 mechanics of ridging in particle-based sea ice models. On a larger 29 scale, this results in ice-pack dynamics prone to stick-slip, strain 30 localization, and limited compressional resistance. 31 32 Slides and video: 33 34 - slides: gopher://adamsgaard.dk/9/npub/seaicemuri2021-damsgaard.pdf 35 - video: https://adamsgaard.dk/video/seaicemuri_damsgaard.mp4 36 37 Several other presentations to the workshop are also already available[2]. 38 39 40 References: 41 [1] https://seaicemuri.org 42 [2] https://seaicemuri.org/presentations.html