Finding Ocean States That Are Consistent with Observations from a Perturbed Physics Parameter Ensemble

• DOI: 10.1175/jcli-d-17-0514.1
• Publication Date: 2018-03-20T19:40:38Z
• Authors: Sarah Sparrow; Richard J. Millar; Kuniko Yamazaki; Neil Massey; Adam C. Povey; Andy Bowery; Roy G. Grainger; David Wallom; Myles Allen
• Keywords: HadCM3; Ensemble average; Climate state; Oceanic basin

A very large ensemble is used to identify subgrid-scale parameter settings for the HadCM3 model that are capable of best simulating ocean state over recent past (1980–2010). simple particle filtering technique based upon agreement basin mean sea surface temperature (SST) and upper 700-m heat content with EN3 observations applied an existing perturbed physics initial conditions perturbations. single set values was identified from wide range sets gave period studied. The set, different standard parameters, has a transient climate response 1.68 K. selected shows improved decadal-mean SST patterns Atlantic meridional overturning circulation (AMOC) at 26°N as measured by Rapid Climate Change (RAPID) array. Particle techniques demonstrated here could have useful role in improving starting point traditional model-tuning exercises coupled models.