Brief communication: On calculating the sea-level contribution in marine ice-sheet models

• Published in: The Cryosphere
• Main Authors: H. Goelzer, V. Coulon, F. Pattyn, B. de Boer, R. van de Wal
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2020
• Subjects: envir; geo; Ice Sheet; The Cryosphere
• Online Access: https://doi.org/10.5194/tc-14-833-2020; https://www.the-cryosphere.net/14/833/2020/tc-14-833-2020.pdf; https://doaj.org/article/ffd80fc2b32b44d9819a617e3e7b639f

Estimating the contribution of marine ice sheets to sea-level rise is complicated by ice grounded below sea level that is replaced by ocean water when melted. The common approach is to only consider the ice volume above floatation, defined as the volume of ice to be removed from an ice column to become afloat. With isostatic adjustment of the bedrock and external sea-level forcing that is not a result of mass changes of the ice sheet under consideration, this approach breaks down, because ice volume above floatation can be modified without actual changes in the sea-level contribution. We discuss a consistent and generalised approach for estimating the sea-level contribution from marine ice sheets.