Session: Benchmarking & cross-cutting Group 1 (Isotope modelling, COMPARE)
Author: Andrew Schurer / A.Schurer@ed.ac.uk / The University of Edinburgh
Co-author: Gabi Hegerl, The University of Edinburgh;
Mike Mineter, The University of Edinburgh;
Simon Tett, The University of Edinburgh;
Large-scale circulation patterns have been shown to have a major influence on regional and global climate on all time-scales. Here we investigate the effect of three of the most important climate modes, the El Niño-Southern Oscillation (ENSO), Southern Annular Mode (SAM) and Northern Atlantic Oscillation (NAO), on decadal-scale variability. We begin our simulations in 1780, driving the HadCM3 model using a particle filter technique so that it matches the observed states of our modes of interest. By comparing the simulated climate produced with that from a free-running ensemble (run using identical boundary conditions) the impact of ensuring that the large scale circulation states are the same as that observed can be determined.