Teleconnections and the Arctic Oscillation observed in the barotropic component of the atmosphere

In this study, teleconnectivity and one point correlations are analyzed for the barotropic component of the atmosphere represented by a simple barotropic model (called barotropic S-model), and the results are compared with observation by the NCEP/NCAR reanalysis. It is confirmed that the teleconnectivity and the PNA pattern are perfectly simulated by the barotropic S-model. The question is focused whether the Arctic Oscillation (AO) would appear by the one point correlation. According to the result, it is found that the one point correlation is not restricted within the Atlantic sector like the NAO, but spread to entire mid-latitudes surrounding the Arctic. The positive correlations in the Pacific sector are all statistically significant at the 5% confidence level. The result suggests that the AO is not a statistical artifact due to the multiple teleconnections of the NAO and PNA, but a physical mode with dynamical basis. The reduced correlation in the observation may be the influence of the transient noise.