Existence, persistence of ice-shelf channels in marine ice sheets

Laboratoire(s) de rattachement : IGE

Encadrant : Lionel Favier

Co-encadrant : Nicolas Jourdain

Niveau de formation & pré-requis : M2R - Parcours Atmosphère-Climat-Surfaces Continentales - UE Cryosphere and/or ocean dynamics

Mots-clés : Ice-shelf channels, ice dynamics, ocean dynamics, ice-ocean coupled model

Ice-shelf channels are ubiquitous in Antarctica and found within almost every ice shelf. They appear as along-flow incisions, often starting from the limit between the grounded and the floating ice, i.e., the grounding line. They are then advected with the ice flow over the ice shelf up to the calving front, and are generally limited to a few kilometers wide. The ice thickness in channels can be half the ice-shelf mean thickness. Channels can affect the stability of both the ice shelf itself and the upstream grounded ice sheet, the latter being a potential contributor to sea level rise, as opposed to the already ice of ice shelves. However, the conditions of their initiation and evolution is not quite resolved. One reason for that lack of knowledge is the fact that they lie at the interface between the ice and the ocean, thus superimposing the complexity of respective physics.
We propose to the candidate to tackle this open question using an ice-ocean coupled model recently developed here at IGE. Part of the work will be to initiate channels from the ice sheet or the ocean under different configurations and caracterize their evolution in regards to changing forcing conditions (e.g., cavity circulation for the oceanographic side or run-off for the glaciological side). Beyond this processus based study, the candidate will assess the effect of those different configurations onto the ice-shelf stability.

Requirements for the candidate : The stage will be at the interface between ice and ocean dynamics. We ask the candidate to either have a good understanding of those topics or a strong motivation to learn. The candidate will have to manipulate different programming language (Python, Fortran...) so we ask him be familiar to at least some of them. Curiosity and eagerness to learn new things are definitely a plus.

Working Environment : The GLACE team is a very strong team composed of ice-sheet and ocean modellers that can convey their expertise on the subject.

Pour candidater : Adresser un CV et une lettre de motivation par email à l’adresse ci-dessous :
lionel.favier univ-grenoble-alpes.fr