Abstract
Although the global-mean sea level (GMSL) rose over the twentieth century with a positive contribution from thermosteric and barystatic (ice sheets and glaciers) sources, the driving processes of GMSL changes during the pre-industrial Common Era (PCE; 1-1850 CE) are largely unknown. Here, the contributions of glacier and ice sheet mass variations and ocean thermal expansion to GMSL in the Common Era (1-2000 CE) are estimated based on simulations with different physical models. Although the twentieth century global-mean thermosteric sea level (GMTSL) is mainly associated with temperature variations in the upper 700 m (86 % in reconstruction and 74 ± 8 % in model), GMTSL in the PCE is equally controlled by temperature changes below 700 m. The GMTSL does not vary more than ± 2 cm during the PCE. GMSL contributions from the Antarctic and Greenland ice sheets tend to cancel each other out during the PCE owing to the differing response of the two ice sheets to atmospheric conditions. The uncertainties of sea-level contribution from land-ice mass variations are large, especially over the first millennium. Despite underestimating the twentieth century model GMSL, there is a general agreement between the model and proxy-based GMSL reconstructions in the CE. Although the uncertainties remain large over the first millennium, model simulations point to glaciers as the dominant source of GMSL changes during the PCE.
| Original language | English |
|---|---|
| Pages (from-to) | 1417-1435 |
| Number of pages | 19 |
| Journal | Earth System Dynamics |
| Volume | 13 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - 17 Oct 2022 |
Bibliographical note
Funding Information:This work was supported by the Fonds National de la Recherche Scientifique (F.R.S.-FNRS-Belgium) within the framework of the project "Evaluating simulated centennial climate variability over the past millennium using global glacier modelling" (grant agreement PDR T.0028.18). Hugues Goosse is Research Director within the F.R.S.-FNRS. We acknowledge the World Climate Research Programme's Working Group on Coupled Modelling, which is responsible for CMIP, and we thank the climate modelling groups for producing and making available their model output. For CMIP, the US Department of Energy's Program for Climate Model Diagnosis and Intercomparison provided coordinating support and led the development of software infrastructure in partnership with the Global Organization for Earth System Science Portals. We thank Jennifer Walker for providing reconstructed sea-level data on request. Computational resources have been provided by the supercomputing facilities of the Université catholique de Louvain (CISM/UCL) and the Consortium des Equipements de Calcul Intensif en FédérationWallonie Bruxelles (CECI) funded by the Fond de la Recherche Scientique de Belgique (F.R.S.-FNRS) under convention 2.5020.11. Ice sheet simulations were performed on resources provided by UNINETT Sigma2 - the National Infrastructure for High Performance Computing and Data Storage in Norway through projects NN8006K, NN9560K, NS5011K, NS8006K and NS9560K. Heiko Goelzer acknowledges support from the Research Council of Norway through projects 270061, 295046 and 324639. Fabien Maussion acknowledges support from the Austrian Science Fund (FWF) grant P30256. We thank Christopher Piecuch and the two anonymous reviewers for providing critical comments and suggestions during the revision of this paper. This research has been supported by the Fonds National de la Recherche Scientifique (F.R.S.-FNRS Belgium; grant agreement PDR T.0028.18).
Funding Information:
This work was supported by the Fonds National de la Recherche Scientifique (F.R.S.-FNRS-Belgium) within the framework of the project “Evaluating simulated centennial climate variability over the past millennium using global glacier modelling” (grant agreement PDR T.0028.18). Hugues Goosse is Research Director within the F.R.S.-FNRS. We acknowledge the World Climate Research Programme's Working Group on Coupled Modelling, which is responsible for CMIP, and we thank the climate modelling groups for producing and making available their model output. For CMIP, the US Department of Energy's Program for Climate Model Diagnosis and Intercomparison provided coordinating support and led the development of software infrastructure in partnership with the Global Organization for Earth System Science Portals. We thank Jennifer Walker for providing reconstructed sea-level data on request. Computational resources have been provided by the supercomputing facilities of the Université catholique de Louvain (CISM/UCL) and the Consortium des Equipements de Calcul Intensif en Fédération Wallonie Bruxelles (CECI) funded by the Fond de la Recherche Scientique de Belgique (F.R.S.-FNRS) under convention 2.5020.11. Ice sheet simulations were performed on resources provided by UNINETT Sigma2 - the National Infrastructure for High Performance Computing and Data Storage in Norway through projects NN8006K, NN9560K, NS5011K, NS8006K and NS9560K. Heiko Goelzer acknowledges support from the Research Council of Norway through projects 270061, 295046 and 324639. Fabien Maussion acknowledges support from the Austrian Science Fund (FWF) grant P30256. We thank Christopher Piecuch and the two anonymous reviewers for providing critical comments and suggestions during the revision of this paper.
Publisher Copyright:
© 2022 Nidheesh Gangadharan et al.