Remapping of Greenland ice sheet surface mass balance anomalies for large ensemble sea-level change projections

• Main Authors: Goelzer, Heiko, Noël, Brice B.P.Y., Edwards, T., Fettweis, Xavier, Gregory, Jonathan, Lipscomb, William W.H., van de Wal, Roderik S W, Van den Broeke, Michiel
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2020
• Subjects: Glaciologie; Greenland; Ice Sheet; The Cryosphere
• Online Access: http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/309155; https://dipot.ulb.ac.be/dspace/bitstream/2013/309155/1/doi_292799.pdf

Future sea-level change projections with process-based stand-alone ice sheet models are typically driven with surface mass balance (SMB) forcing derived from climate models. In this work we address the problems arising from a mismatch of the modelled ice sheet geometry with the geometry used by the climate model. We present a method for applying SMB forcing from climate models to a wide range of Greenland ice sheet models with varying and temporally evolving geometries. In order to achieve that, we translate a given SMB anomaly field as a function of absolute location to a function of surface elevation for 25 regional drainage basins, which can then be applied to different modelled ice sheet geometries. The key feature of the approach is the non-locality of this remapping process. The method reproduces the original forcing data closely when remapped to the original geometry. When remapped to different modelled geometries it produces a physically meaningful forcing with smooth and continuous SMB anomalies across basin divides. The method considerably reduces non-physical biases that would arise by applying the SMB anomaly derived for the climate model geometry directly to a large range of modelled ice sheet model geometries. SCOPUS: ar.j info:eu-repo/semantics/published