What Controls Recent Changes in the Circulation of the Southern Hemisphere: Polar Stratospheric or Equatorial Surface Temperatures?


Recent research suggests that both tropical ocean warming and stratospheric temperature anomalies due to ozone depletion have led to a poleward displacement of the midand high-latitude circulation of the Southern Hemisphere over the past century. In this study, we attempt to distinguish the influences of ocean warming and stratospheric cooling trends on seasonal changes of both the zonally symmetric and asymmetric components of the southern hemisphere circulation. Our analysis makes use of three data sets-the ERA40 reanalysis and results from two different runs of the GFDL global atmosphere and land model (AM2.1) for the period 1870 to 2004. A regression analysis was applied to two variables in each of the three data sets-the zonal component of the surface wind U(10 m) and the height at 300 hPato determine their correlation with zonally averaged polar stratospheric temperatures (T_polarat 150 hPa, averaged over a band from 70S - 80S) and low-level equatorial temperatures (T_equatorat 850 hPa averaged over a band at 5S - 5N). Our analysis shows that the zonally symmetric surface winds have a considerably enhanced intensity in high latitudes of the southern hemisphere over the summer period, and that the stratospheric temperature trend, and thus ozone depletion, is the dominant contributor to that change. However, the climatic change of the asymmetric component of zonal wind component at z = 10 m (U10) as well as of 300hPa heights has been found to be large for both summer and winter periods. Our regression results show that correlation with T_equator (our proxy for global warming) explains most of the climatic changes for the asymmetric component of U10 and 300 hPa heights for summer and winter periods, suggesting the influence of warming of the global oceans on anticyclones south of the Indian Ocean and south-eastern Pacific Ocean.

Share and Cite:

I. Orlanski, "What Controls Recent Changes in the Circulation of the Southern Hemisphere: Polar Stratospheric or Equatorial Surface Temperatures?," Atmospheric and Climate Sciences, Vol. 3 No. 4, 2013, pp. 497-509. doi: 10.4236/acs.2013.34052.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] D. W. J. Thompsonand S. Solomon, “Interpretation of Recent Southern Hemisphere Climate Change,” Science, Vol. 296, No. 5569, 2002, pp. 895-899.
[2] C. Archer and K. Caldeira, “Historical Trends in the Jet Streams,” Geophysical Research Letters, Vol. 35, No. 8, 2008, Article ID: L08803, http://dx.doi.org/10.1029/2008GL033614
[3] G. J. Marshall, “Trends in the Southern Annular Mode from Observations and Reanalysis,” Journal of Climate, Vol. 16, No. 24, 2003, pp. 4134-4143.
[4] Q. Fu, J. C. Wallace and J. Reitchler, “Enhanced MidLatitude Tropospheric Warming in Satellite Measurements,” Science, Vol. 312, No. 5777, 2006, p. 1179. http://dx.doi.org/10.1126/science. 1125566
[5] Y. Hu and Q. Fu, “Observed Poleward Expansion of the Hadley Circulation Since 1979,” Atmospheric Chemistry and Physics, Vol. 7, 2007, pp. 5229-5236. http://dx.doi.org/10.5194/acp-7-5229-2007
[6] J. Lu, G. A. Vecchi and T. Reichler, “Expansion of the Hadley Cell under Global Warming,” Geophysical Research Letters, Vol. 34, 2007, Article ID: L06805. http://dx.doi.org/10.1029/2006GL028443
[7] C. Vera, G. Silvestri, B. Liebmann and P. Gonzalez, “Climate Change Scenarios for Seasonal Precipitacion in South America from IPCC-AR4 Models,” Geophysical Research Letters, Vol. 33, 2006, Article ID: L13707.
[8] S. Solman and I. Orlanski, “Subpolar High Anomaly Preconditioning Precipitation over South America,” Journal of the Atmospheric Sciences, Vol. 67, No. 5, 2010, pp. 1526-1542. http://dx.doi.org/10.1175/ 2009JAS3309.1
[9] B. L. Preston and R. N. Jones, “Climate Change Impacts on Australia and the Benefits of Early Action to Reduce Global Greenhouse Gas Emissions,” Report CSIRO, 2006.
[10] H. D. Pritchard, et al., “Antarctic Ice-Sheet Loss Driven by Basal Melting of Ice Shelves,” Nature, Vol. 484, 2012, pp. 502-505. http://dx.doi.org/10.1038/nature10968
[11] D. G. Vaughn, G. J. Marshall, W. M. Connolley, C. Parkinson, R. Mulvaney, D. A. Hodgson, J. C. King, J. C. Pudsey and J. Turner, “Recent Rapid Regional Climate Warming in the Antarctic Peninsula,” Climate Change, Vol. 60, 2003, pp. 243-274.
[12] J. Turner and J. Overland, “Contrasting Climate Change in the Two Polar Regions,” Polar Research, Vol. 28, No. 2, 2009, pp. 146-164. http://dx.doi.org/10.1111/j.1751-8369.2009.00128.x
[13] J. Turner, T. A. Lachlan-Cope, S. Colwell, G. J. Marshall and W. M. Connolley, “Significant Warming of the Antarctic Winter Troposphere,” Science, Vol. 311, No. 5769, 2006, pp. 1914-1917. http://dx.doi.org/10.1126/science.1121652
[14] E. J. Steig, D. P. Schneider, S. D. Rutherford, M. E. Mann, J. C. Comiso and D. T. Shindell, “Warming of the Antarctic Ice-Sheet Surface Since the 1957 International Geophysical Year,” Nature, Vol. 1457, No. 7228, 2009, pp. 459-463. http://dx.doi.org/10.1038/nature07669
[15] R. W. Hobbs and M. N. Raphael, “Characterizing the Zonally Asymmetric Component of the SH Circulation,” Climate Dynamics, Vol. 35, 2010, pp. 859-873.
[16] N. Mathewman and G. Magnusdottir, “Clarifying Ambiguity in Intraseasonal Sothern Hemisphere Climate Modes during Austral Winter,” Journal of Geophysical Research, Vol. 113, No. D7, 2012, Article ID: D03105.
[17] K. C. Mo and J. N. Paegle, “The Pacific-South American Modes and Their Downstream Effects,” International Journal of Climatology, Vol. 21, No. 10, 2001, pp. 1211-1229.
[18] L.-M. Polvani, D. W. Waugh, G. J. P. Correa and S.-W. Son, “Stratospheric Ozone Depletion: The Main Driver of Twentieth-Century Atmospheric Ciruclation Changes in the Southern Hemisphere,” Journal of Climate, Vol. 24, 2011, pp. 795-812.
[19] S. M. Uppala, et al., “The ERA-40 Re-Analysis,” Quarterly Journal of the Royal Meteorological Society, Vol. 131, 2005, pp. 2961-3012.
[20] J. Anderson, et al., “The New GFDL Global Atmosphere and Landmodel AM2/LM2: Evaluation with Prescribed SST Simulations,” Journal of Climate, Vol. 17, 2004, pp. 4641-4673.
[21] D. W. J. Thompson, J. M. Wallace and G. C. Hegerl, “Annular Modes in the Extra-Tropical Circulation, Part II: Trends,” Journal of Climate, Vol. 13, 2000, p. 1018.
[22] L. Polvani and P. J. Kushner, “Tropospheric Response to Stratospheric Perturbations in a Relatively Simple General Circulation Model,” Geophysical Research Letters, Vol. 29, No. 7, 2002, 18 p. http://dx.doi.org/10.1029/2001GL014284
[23] G. Chen and I. M. Held, “Phase Speed Spectra and the Recent Poleward Shift of Southern Hemisphere Surface Westerlies,” Geophysical Research Letters, Vol. 34, No. 21, 2007, Article ID: L21805. http://dx.doi.org/10.1029/2007GL031200
[24] P. Kushner, I. M. Held and T. L. Delworth, “Southern Hemisphere Atmospheric Circulation Response to Global Warming,” Journal of Climate, Vol. 14, No. 10, 2001, pp. 2238-2249. http://dx.doi.org/10.1175/1520-0442(2001) 014<0001:SHACRT>2.0.CO;2
[25] K. E. Trenberth and K. C. Mo, “Blocking in the Southern Hemisphere,” Monthly Weather Review, Vol. 113, No. 1, 1985, pp. 3-21.
[26] I. Orlanski and S. Solman, “The Mutual Interaction between External Rossby Waves and Thermal Forcing: The Sub-Polar Region,” Journal of the Atmospheric Sciences, Vol. 67, 2010, pp. 2018-2038.

Copyright © 2020 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.