Variable temperature thresholds of melt pond formation on Antarctic ice shelves

Variable temperature thresholds of melt pond formation on Antarctic ice shelves

van Wessem, J. Melchior (Universiteit Utrecht)
van den Broeke, Michiel R. (Universiteit Utrecht)
Wouters, B. (TU Delft Physical and Space Geodesy; Universiteit Utrecht)
Lhermitte, S.L.M. (TU Delft Mathematical Geodesy and Positioning; Katholieke Universiteit Leuven)

2023

It has been argued that the −5 °C annual mean 2 m air temperature isotherm defines a limit of ice shelf viability on the Antarctic Peninsula as melt ponding increases at higher temperatures. It is, however, presently unknown whether this threshold can also be applied to other Antarctic ice shelves. Here we use two present-day and three future high-resolution Antarctic climate simulations to predict warming thresholds for Antarctic ice shelf melt pond formation on the basis of the melt-over-accumulation ratio. The associated warming thresholds match well with observed melt pond volumes and are found to be spatially highly variable and controlled by snow accumulation. For relatively wet ice shelves, the −5 °C temperature threshold was confirmed; but cold and dry ice shelves such as Amery, Ross and Filchner-Ronne are more vulnerable than previously thought, with threshold temperatures well below −15 °C. Coupled Model Intercomparison Project Phase 6 models predict that towards the end of this century these thresholds can be reached on many ice shelves, even on cold ice shelves and under moderate warming scenarios.

http://resolver.tudelft.nl/uuid:8b6dfc5e-de4a-45c0-8bc8-8b595193629e

https://doi.org/10.1038/s41558-022-01577-1

1758-678X

Nature Climate Change, 13 (2), 1-11

Institutional Repository

journal article

© 2023 J. Melchior van Wessem, Michiel R. van den Broeke, B. Wouters, S.L.M. Lhermitte