Intra‐ and inter‐hemispheric teleconnections using seasonal southern hemisphere sea level pressure

Abstract

AbstractIn this study spatial and temporal relationships involving Southern Hemisphere (SH) sea level pressure (SLP) were examined using a 25‐year data set assembled for this purpose, with special emphasis on discovering inter‐hemispheric teleconnections in the seasonal SLP field. Principal component and correlation analysis was employed. The most important findings include: Season‐to‐season autocorrelation of SLP is at least as large in the SH as in the Northern Hemisphere (NH), though the amount of area of significant autocorrelation is not great in either hemisphere (i.e. a total global area of 17‐24 per cent). Principal component (PC) analysis performed on SH SLP in conjunction with Monte Carlo tests of significance showed that three or four PCs, explaining 40 to 58 per cent of the variance, represent the climatic signal in the data set. Field significance tests applied to each teleconnection map, produced for each grid point in the SH, implied that there is a strong likelihood of real inter‐hemispheric relationships in NH winter. There was much less certainty in the other seasons. Examination of significant teleconnection maps suggested SH links to the Southern Oscillation, the North Atlantic Oscillation, Siberian High strength, and the ‘West Pacific pattern’ described by Wallace and Gutzler (1981).