Journal article

The mean structure and temporal variability of the semiannual oscillation in the southern extratropics

I Simmonds, DA Jones

International Journal of Climatology | JOHN WILEY & SONS LTD | Published : 1998


The semiannual oscillation of the pressure and mid-tropospheric baroclinicity in the southern extratropics has been studied using 21 years (1973-1993) of numerical Southern Hemisphere analyses and long series of pressure data from a number of mid- and high latitude stations. Using recent data and techniques not previously documented, this study has verified that the semiannual oscillation is an important but highly variable feature of the annual cycle of pressure and meridional temperature gradient. In the pressure, the half-yearly wave attains its greatest amplitudes in the mid-latitude ocean basins and on the Antarctic periphery, with a minimum near 55°S. The semiannual oscillation of the ..

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University of Melbourne Researchers