Session: Cross-cutting Group 2 (Paleovar, Past to future, Data assimilation)
Author: Masakazu Yoshimori / email@example.com / Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Japan
Co-author: Marina Suzuki, Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan;
Ayako Abe-Ouchi, Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Japan;
There remain substantial uncertainties in the future projections of Arctic climate change. Schmidt et al. (2013) advocated potential of constraining the uncertainties by making use of both paleoclimate simulations and archives. Indeed, they found a statistical correlation in sea ice changes between the mid-Holocene (MH) and the future with respect to the modern period. It was unclear, however, why such a relation emerges and what the mechanism behind the relation is. We conducted a surface energy balance analysis on 10 CMIP5/PMIP3 atmosphere-ocean general circulation models for climate changes under MH forcing and future RCP4.5 scenario forcing. We found that many common dominant processes that amplify the Arctic warming from late autumn to winter exist between the two periods, despite of the completely different external forcing (insolation vs. GHGs). We also quantified the contribution of individual processes to the inter-model variance of the surface temperature changes. The controlling term varies with seasons, and the details will be presented. Based on the understanding of Arctic warming mechanism from this study, we conclude that paleo-archive recording the Arctic warming at the MH must contain the useful information relevant to the future Arctic climate change.