Sea level fingerprints caused by land ice mass loss

• Main Authors: Brunnabend, Sandra-Esther, Rietbroek, Roelof, Jensen, Laura, Schröter, Jens, Kusche, Jürgen
• Format: Conference Object
• Language: unknown
• Published: 2012
• Subjects: Arctic Ocean; glaciers; Greenland; Ice Sheet; North Atlantic; Sea ice; Alaska
• Online Access: https://epic.awi.de/id/eprint/33751/; https://hdl.handle.net/10013/epic.42177

Relative sea level change of the recent past has several sources. Beside the thermo‐steric contribution, which is caused by ocean warming, the mass loss of land ice is a major source. Generally, the additional mass in the ocean corresponds to an increase in global mean sea level. In addition, the redistribution of mass influences relative sea level through gravitational attraction and ocean floor deformation. As result, the relative sea level decreases near the source of the ice mass loss and slightly increases at greater distances. The freshening of the ocean induces further local changes in relative sea level. Regionally, the different signals in relative sea level change caused by mass loss of the major ice sheets and glaciers in Alaska are identified using an inverse 'fingerprint' method. The different signals are assumed to have a fixed spatial pattern. The mass‐driven temporal contributions are subsequently estimated by analysing GRACE measurements. The steric contribution is evaluated using satellite altimetry. However, the freshening of the ocean water also leads to patterns of sea level change that are not spatially fixed, but change in time. To identify this steric contribution the finite element sea‐ice ocean model (FESOM) has been used. In a case study, an experiment has been performed that simulates sea level change using different melting scenarios for the Greenland Ice Sheet (theoretical melt rates and derived by other studies). Here, a clear signal is found in the North Atlantic and the Arctic Ocean.