EGU21-16334
https://doi.org/10.5194/egusphere-egu21-16334
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Reassessing global ice volume: uncertainty and structure in sea level records

Fiona D. Hibbert1,2, Felicity Williams2, and Eelco Rohling2,3
Fiona D. Hibbert et al.
  • 1Department of Environment and Geography, University of York, York YO10 5NG UK
  • 2Research School of Earth Sciences, The Australian National University, Canberra, ACT, 2601, Australia
  • 3Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton SO14 3ZH, UK

Geologically recorded sea-level variations represent the sum total of all contributing processes, be it known or unknown, and may thus help in finding the full range of future sea-level rise. Significant sea-level-rise contributions from both northern and southern ice sheets are not unprecedented in the geological record and offer a well-constrained range of natural scenarios from intervals during which ice volumes were similar to or smaller than present (i.e., interglacial periods), to intervals during which total ice volume was greater (i.e., glacial periods).

The last deglaciation is the most recent period of widespread destabilisation and collapse of major continental ice sheets. Records spanning the last deglaciation (as well as the ice volume maxima) are few, fragmentary and seemingly inconsistent (e.g., the timing and magnitude of melt-water pulses), in part due to locational (tectonic and glacio-isostatic) as well as modern analogue considerations (e.g., palaeo-water depth or facies formation depth). We present a new synthesis of sea-level indicators, with particular emphasis on the geological and biological context, as well as the uncertainties of each record. Using this new compilation and the novel application of statistical methods (trans-dimensional change-point analysis, which avoids “overfitting” of noise in the data), we will assess global ice-volume changes, sea-level fluctuations and changes in climate during the last deglaciation. Finally, we discuss the implications of these uncertainties on our ability to constrain past cryosphere changes.

How to cite: Hibbert, F. D., Williams, F., and Rohling, E.: Reassessing global ice volume: uncertainty and structure in sea level records, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-16334, https://doi.org/10.5194/egusphere-egu21-16334, 2021.

Corresponding presentation materials formerly uploaded have been withdrawn.