Journal cover Journal topic
Climate of the Past An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 3.174 IF 3.174
  • IF 5-year value: 3.841 IF 5-year 3.841
  • CiteScore value: 3.48 CiteScore 3.48
  • SNIP value: 1.078 SNIP 1.078
  • SJR value: 1.981 SJR 1.981
  • IPP value: 3.38 IPP 3.38
  • h5-index value: 42 h5-index 42
  • Scimago H index value: 58 Scimago H index 58
Volume 14, issue 10 | Copyright
Clim. Past, 14, 1463-1485, 2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.

Research article 19 Oct 2018

Research article | 19 Oct 2018

Eemian Greenland SMB strongly sensitive to model choice

Andreas Plach1, Kerim H. Nisancioglu1,2, Sébastien Le clec'h3,4, Andreas Born1,5,6, Petra M. Langebroek7, Chuncheng Guo7, Michael Imhof8,5, and Thomas F. Stocker5,6 Andreas Plach et al.
  • 1Department of Earth Science, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway
  • 2Centre for Earth Evolution and Dynamics, University of Oslo, Oslo, Norway
  • 3Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
  • 4Earth System Science and Department Geografie, Vrije Universiteit Brussel, Brussels, Belgium
  • 5Climate and Environmental Physics, Physics Institute, University of Bern, Bern, Switzerland
  • 6Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
  • 7Uni Research Climate and Bjerknes Centre for Climate Research, Bergen, Norway
  • 8Laboratory of Hydraulics, Hydrology and Glaciology, ETH Zürich, Zürich, Switzerland

Abstract. Understanding the behavior of the Greenland ice sheet in a warmer climate, and particularly its surface mass balance (SMB), is important for assessing Greenland's potential contribution to future sea level rise. The Eemian interglacial period, the most recent warmer-than-present period in Earth's history approximately 125000 years ago, provides an analogue for a warm summer climate over Greenland. The Eemian is characterized by a positive Northern Hemisphere summer insolation anomaly, which complicates Eemian SMB calculations based on positive degree day estimates. In this study, we use Eemian global and regional climate simulations in combination with three types of SMB models – a simple positive degree day, an intermediate complexity, and a full surface energy balance model – to evaluate the importance of regional climate and model complexity for estimates of Greenland's SMB. We find that all SMB models perform well under the relatively cool pre-industrial and late Eemian. For the relatively warm early Eemian, the differences between SMB models are large, which is associated with whether insolation is included in the respective models. For all simulated time slices, there is a systematic difference between globally and regionally forced SMB models, due to the different representation of the regional climate over Greenland. We conclude that both the resolution of the simulated climate as well as the method used to estimate the SMB are important for an accurate simulation of Greenland's SMB. Whether model resolution or the SMB method is most important depends on the climate state and in particular the prevailing insolation pattern. We suggest that future Eemian climate model intercomparison studies should include SMB estimates and a scheme to capture SMB uncertainties.

Publications Copernicus
Short summary
The Greenland ice sheet is a huge frozen water reservoir which is crucial for predictions of sea level in a warming future climate. Therefore, computer models are needed to reliably simulate the melt of ice sheets. In this study, we use climate model simulations of the last period where it was warmer than today in Greenland. We test different melt models under these climatic conditions and show that the melt models show very different results under these warmer conditions.
The Greenland ice sheet is a huge frozen water reservoir which is crucial for predictions of sea...