Bathymetry-constrained warm-mode melt estimates derived from analysing oceanic gateways in Antarctica
Year: 2025
Type: article
Abstract: . Melting underneath the floating ice shelves surrounding the Antarctic continent is a key process for the stability of the Antarctic Ice Sheet and therefore its current and future mass loss. Troughs and sills on the continental shelf play a crucial role in modulating sub-shelf melt rates, as they can allow or block the access of relatively warm, modified Circumpolar Deep Water to ice-shelf cavities. Here we identify potential oceanic gateways that could allow the access of warm water masses to Antarctic grounding lines based on critical access depths inferred from high-resolution bathymetry data. We analyse the properties of water masses that are currently present in front of the ice shelf and that might intrude into the respective ice-shelf cavities in the future. We use the ice-shelf cavity model PICO to estimate an upper limit of melt rate changes in case all warm water masses up to a certain depth level gain access to the cavities. We find that melt rates could increase in all regions at least by a factor of 2. Depending on the presence or absence of an oceanic gateway and the current ice-shelf melt conditions we find up to 200-fold larger melt rates. The identification of oceanic gateways is thus valuable for assessing the potential of ice-shelf cavities to switch from a 'cold' to a 'warm' state, which could result in widespread ice loss from Antarctica.
Source: The cryosphere
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,574
Awards: Rethinking Antarctic Sea Level Projections (RASP), G199372248, G229637716, PROjecTing sEa-level rise : from iCe sheets to local implicaTions, G4232367243, G434337789, Tipping Points in Antarctic Climate Components, G5285415500, G5826175352, PalMod II Verbundprojekt: WP CC.1 Modellkopplung und Laufzeitoptimierung - TP4: Entwicklung des PICO-Modells zu einem ?pop-up?-Modell für transiente Glazialsimulationen, G6622453712, PalMod III - Verbundprojekt WP 1.4 Instabilitäten der Eisschilde - TP: 2 Interaktion vom Grönländischen und Antarktischen Eisschild mit dem globalen Klimasystem und der festen Erde
OpenAlex ID: W4411708646