Reconstructing winter climate anomalies in the Euro-Atlantic sector using circulation patterns

Abstract. The efficacy of Euro-Atlantic circulation regimes for estimating wintertime climate anomalies (precipitation and surface temperature) over Europe is assessed. A comparison seasonal reconstructions from two different regime frameworks (cluster analysis the low-level zonal flow, traditional blocking indices) presented contrasted with using North Atlantic Oscillation (NAO) index. are quantitatively evaluated correlations coefficient efficiency, accounting misfit in phase amplitude. skill various classifications reconstructing depends on variable region interest. jet found to capture more spatial structure precipitation than NAO, framework showing generally better relative indices. temperature have lower those precipitation, best results obtained by NAO high-latitude southern Europe. All methods underestimate magnitude due large variability within each classification pattern.