Impact of tide‐topography interactions on basal melting of Larsen C Ice Shelf, Antarctica

摘要: [1] Basal melting of ice shelves around Antarctica contributes to formation Antarctic Bottom Water and can affect global sea level by altering the offshore flow grounded streams glaciers. Tides influence shelf basal melt rate (wb) contributing ocean mixing mean circulation as well thermohaline exchanges with shelf. We use a three-dimensional model, thermodynamically coupled nonevolving shelf, investigate relationship between topography, tides, andwb for Larsen C Ice Shelf (LCIS) in northwestern Weddell Sea, Antarctica. Using our best estimates thickness seabed we find that largest modeled LCIS rates occur northeast, where model predicts strong diurnal tidal currents (∼0.4 m s−1). This distribution is significantly different from models no forcing, which predict along deep grounding lines. compare several runs explore sensitivity geometry, initial potential temperature (θ0), thermodynamic parameterizations heat freshwater ice-ocean exchange, forcing. The resulting range LCIS-averagedwb ∼0.11–0.44 a−1. spatial wb very sensitive geometry parameterization while overall magnitude influenced θ0. These sensitivities wbpredictions reinforce need high-resolution maps draft sub-ice-shelf topography together measurements at front improve representation climate system models.