A Last Glacial Maximum World-Ocean simulation at eddy-permitting resolution – Part 2: Confronting the paleo-proxy data
Author:
Ballarotta M., Döös K.ORCID, Lundberg P., Brodeau L., Brandefelt J.
Abstract
Abstract. Previous investigations concerning the design of an eddy-permitting LGM oceanic simulation are here extended with focus on whether this type of simulation is capable of improving the numerical results with regard to the available paleo-proxy reconstructions. Consequently, an eddy-permitting and two coarse-grid simulations of the same LGM period are confronted with a dataset from the Multiproxy Approach for the Reconstruction of the Glacial Ocean Sea Surface Temperatures (MARGO SSTs) and a number of sea-ice reconstructions. From a statistical analysis it was found that the eddy-permitting simulation does not significantly improve the SST representation with regard to the paleo-reconstructions. The western boundary currents are better resolved in the high-resolution experiment than in the coarse simulations, but, although these more detailed SST structures yield a locally improved consistency between modelled predictions and proxies, they do not contribute significantly to the global statistical score. As in the majority of the PMIP2 simulations, the modelled sea-ice conditions are still inconsistent with the paleo-reconstructions, probably due to the choice of the model equilibrium.
Publisher
Copernicus GmbH
Reference16 articles.
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