Brief Communication: Sensitivity of Antarctic ice-shelf melting to ocean warming across basal melt models

The uncertain sensitivity of Antarctic ice-shelf basal melt to ocean warming strongly contributes to uncertainties in sea-level projections. Here, we explore the response of five dedicated basal melt models to an idealised sub-thermocline 1 °C warming and find a large intermodel spread with total melt increases between 67 % and 240 %. For deep regions of presentlyfast-melting ice shelves, this spread can reach two orders of magnitude. We conclude that a consistent calibration on present-conditions does not guarantee consistent melt sensitivities and that diversity in basal melt forcing is presently unavoidable to prevent underestimating uncertainties in future projections.