Arctic sea ice simulation in the PlioMIP ensemble

• Published in: Climate of the Past
• Main Authors: Howell, F. W., Haywood, A. M., Otto-Bliesner, B. L., Bragg, F., Chan, W. L., Chandler, M. A., Contoux, C., Kamae, Y., Abe-Ouchi, A., Rosenbloom, N. A., Stepanek, C., Zhang, Z. S.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2016
• Subjects: model intercomparison project; mid-pliocene climate; meridional; overturning circulation coupled model experimental-design; warm period ocean cover; variability thickness; Arctic; Sea ice
• Online Access: https://hdl.handle.net/1983/4c038c28-8669-49ea-bff6-ac0700dc2c1f; https://research-information.bris.ac.uk/en/publications/4c038c28-8669-49ea-bff6-ac0700dc2c1f; https://doi.org/10.5194/cp-12-749-2016; https://research-information.bris.ac.uk/ws/files/110332314/cp_12_749_2016.pdf; https://research-information.bris.ac.uk/ws/files/110332316/cp_12_749_2016_supplement.pdf

Eight general circulation models have simulated the mid-Pliocene warm period (mid-Pliocene, 3.264 to 3.025 Ma) as part of the Pliocene Modelling Intercomparison Project (PlioMIP). Here, we analyse and compare their simulation of Arctic sea ice for both the pre-industrial period and the mid-Pliocene. Mid-Pliocene sea ice thickness and extent is reduced, and the model spread of extent is more than twice the pre-industrial spread in some summer months. Half of the PlioMIP models simulate ice-free conditions in the mid-Pliocene. This spread amongst the ensemble is in line with the uncertainties amongst proxy reconstructions for mid-Pliocene sea ice extent. Correlations between mid-Pliocene Arctic temperatures and sea ice extents are almost twice as strong as the equivalent correlations for the pre-industrial simulations. The need for more comprehensive sea ice proxy data is highlighted, in order to better compare model performances.