Remember Me
Or use your Academic/Social account:


Or use your Academic/Social account:


You have just completed your registration at OpenAire.

Before you can login to the site, you will need to activate your account. An e-mail will be sent to you with the proper instructions.


Please note that this site is currently undergoing Beta testing.
Any new content you create is not guaranteed to be present to the final version of the site upon release.

Thank you for your patience,
OpenAire Dev Team.

Close This Message


Verify Password:
Verify E-mail:
*All Fields Are Required.
Please Verify You Are Human:
fbtwitterlinkedinvimeoflicker grey 14rssslideshare1
Meehl, Gerald A.; Hurrell, James W.; Loon, Harry Van (2011)
Publisher: Co-Action Publishing
Journal: Tellus A
Languages: English
Types: Article
The local pressure changes associated with the twice-annual contraction/intensification andexpansion/weakening of the circumpolar trough of low pressure around Antarctica, termed thesemiannual oscillation (SAO), was the dominant signal in the annual cycle at mid and highsouthern latitudes before 1979. The mechanism, as shown by Van Loon (1967), arises fromdifferent response to the surface heat budget over the polar continent and the midlatitude ocean.It has subsequently been shown that in most years since 1979 the SAO has weakened considerably.Evidence is presented here from surface temperature data, 500 mb temperatures from astation pair and zonal mean 500 mb temperatures from the NCAR/NCEP reanalyses to showthat a warming trend since 1979 has not been evenly distributed through the year at eachlatitude. Thus an anomalous change in the temperature gradient between 50°S and 65°S, withpeaks in roughly May and November, has modulated the mechanism that produces the SAO,with its peaks in March and September. Consequently, the magnitude of the SAO has decreasedin the more recent period.DOI: 10.1034/j.1600-0870.1998.t01-3-00005.x
  • The results below are discovered through our pilot algorithms. Let us know how we are doing!

    • Bottomly, M., Folland, C. K., Hsiung, J., Newell, R. E. and Parker, D. E. 1990. Global ocean surface temperature atlas, The UK Met. OYce., Bracknell, 20 pp. and 313 plates.
    • Brankovic, C., Palmer, T. N. and Ferranti, L. 1994. Predictability of seasonal atmospheric variations. J. Climate 7, 217-237.
    • Graham, N. E. 1994. Decadal-scale climate variability in the 1970s and 1980s: Observations and model results. Cli. Dyn. 10, 135-162.
    • Hurrell, J. W. and Van Loon, H. 1994. A modulation of the atmospheric annual cycle in the Southern Hemisphere. T ellus 46A, 325-338.
    • IPCC (Intergovernmental Panel on Climate Change), 1996. Climate change 1995: the science of climate change. Contribution of Working Group I to the Second Assessment Report of the Intergovernmental Panel on Climate change, J. T. Houghton, L. G. Meira Filho, G. A. Callander, N. Harris, A. Kattenberg, and K. Maskell, eds. Cambridge University Press, Cambridge, 572 pp.
    • Jones, P. D. 1994. Hemispheric surface air temperature variations: A reanalysis and an update to 1993. J. Climate 7, 1794-1802.
    • Kalnay, E., Kanamitsu, M., Kistler, R., Collins, W., Deaven, D., Gandin, L., Iredell, M., Saha, S., White, G., Woollen, J., Zhu, Y., Chelliah, M., Ebisuzaki, W., Higgins, W., Janowiak, J., Mo, K. C., Ropelewski, C., Leetma, A., Reynolds, R. and Jenne, R. 1996. The NCEP/NCAR Reanalysis Project. Bull. Amer. Meteorol. Soc. 77, 437-471.
    • Kitoh, A., Yamazaki K., and Tokioka, T. 1990. The double jet and semi-annual oscillations in the Southern Hemisphere simulated by the Meteorological Research Institute general circulation model. J. Meteorol. Soc. Japan 68, 251-264.
    • Large, W. G. and Van Loon, H. 1989. Large-scale, low frequency variability of the 1979 FGGE surface buoy drifts and winds over the Southern Hemisphere. J. Phys. Oceanogr. 19, 216-232.
    • Latif, M. and Barnett, T. P. 1996. Decadal climate variability over the North Pacific and North America: dynamics and predictability. J. Climate 9, 2407-2423.
    • Lau, N.-C. and Nath, M. J. 1994. A modeling study of the relative roles of tropical and extratropical SST anomalies in the variability of the global atmosphereocean system. J. Climate 7, 1184-1207.
    • Manabe, S. and StouVer, R. J. 1996. Low-frequency variability of surface air temperature in a 1000-y integration of a coupled atmosphere-ocean-land surface model. J. Climate 9, 376-393.
    • Mann, M. E. and Park, J. 1996. Greenhouse warming and changes in the seasonal cycle of temperature: model versus observations. Geophys. Res. L ett. 23, 1111-1114.
    • Meehl, G. A. 1991. A reexamination of the mechanism of the semiannual oscillation in the Southern Hemisphere. Journal of Climate 4, 911-926.
    • Meehl, G. A. and Albrecht, B. A. 1988. Tropospheric temperatures and Southern Hemisphere circulation. Mon. Wea. Rev. 116, 953-960.
    • Palmer, T. N. and Sun, Z. 1985. A modelling and observational study of the relationship between sea surface temperature in the north-west Atlantic and the atmospheric general circulation. Quart. J. Roy. Meteor. Soc. 111, 947-975.
    • Parker, D. E., Jackson, M. and Horton, E. B. 1995. T he GISST 2.2 sea surface temperature and sea ice climatology. Climate Research Technical note 63, Hadley Centre, Bracknell, UK, 36 pp.
    • Simmonds, I. and Jones, D. A. 1998. The mean structure and temporal variability of the semiannual oscillation in the southern extratropics. Int. J. Climatol. 18, 473-504.
    • Simmonds, I. and Walland, D. J. 1998. Decadal and centennial variability of the southern semiannual oscillation simulated in the GFDL coupled GCM. Cli. Dyn. 14, 45-53.
    • Sinclair, M. R. 1994. An objective cyclone climatology of the Southern Hemisphere. Mon. Wea. Rev. 122, 2239-2256.
    • Thomson, D. J. 1995. The seasons, global temperature, and precession. Science 268, 59-68.
    • Trenberth, K. E., Large, W. G. and Olson, J. G. 1990. The mean annual cycle in global ocean wind stress. J. Phys. Oceanogr. 20, 1742-1760.
    • Tzeng, R.-Y., Bromwich, D. H. and Parish, T. R. 1993. Present-day Antarctic climatology of the NCAR Community Climate Model Version 1. J. Climate 6, 205-226.
    • Van Loon, H. 1967. The half-yearly oscillations in middle and high southern latitudes and the coreless winter. J. Atmos. Sci. 24, 472-486.
    • Van Loon, H. 1972. Wind in the Southern Hemisphere. Meteorology of the Southern Hemisphere. Meteor. Monogr. no. 35, Amer. Meteor. Soc., 87-100.
    • Van Loon, H. and Rogers, J. C. 1984. Interannual variations in the half-yearly cycle of pressure gradients and zonal wind at sea level on the Southern Hemisphere. T ellus 36A, 76-86.
    • Van Loon, H., Kidson, F. W. and Mullan, A. B. 1993. Decadal variation of the annual cycle in the Australian dataset. J. Climate 6, 1227-1231.
    • Weickmann, K. M. and Chervin, R. M. 1988. The observed and simulated atmospheric seasonal cycle (I). Global wind field modes. J. Climate 1, 165-289.
    • Xu, J.-S., Von Storch, H. and Van Loon, H. 1990. The performance of four spectral GCMs in the Southern Hemisphere: the January and July climatology and the semiannual wave. J. Climate 3, 53-70.
  • No related research data.
  • No similar publications.

Share - Bookmark

Cite this article

Collected from