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Widening of the tropical belt in a changing climate

Abstract

Some of the earliest unequivocal signs of climate change have been the warming of the air and ocean, thawing of land and melting of ice in the Arctic. But recent studies are showing that the tropics are also changing. Several lines of evidence show that over the past few decades the tropical belt has expanded. This expansion has potentially important implications for subtropical societies and may lead to profound changes in the global climate system. Most importantly, poleward movement of large-scale atmospheric circulation systems, such as jet streams and storm tracks, could result in shifts in precipitation patterns affecting natural ecosystems, agriculture, and water resources. The implications of the expansion for stratospheric circulation and the distribution of ozone in the atmosphere are as yet poorly understood. The observed recent rate of expansion is greater than climate model projections of expansion over the twenty-first century, which suggests that there is still much to be learned about this aspect of global climate change.

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Figure 1: What climatological features distinguish the tropics?
Figure 2: Changes in several estimates of the width of the tropical belt since 1979.

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References

  1. Gnanadesikan, A. & Stouffer, R. J. Diagnosing atmosphere-ocean general circulation model errors relevant to the terrestrial biosphere using the Köppen climate classification. Geophys. Res. Lett. 33, L22701 (2006).

    Article  Google Scholar 

  2. Lee, S. & Kim, H.-K. The dynamical relationship between subtropical and eddy-driven jets. J. Atmos Sci. 60, 1490–1503 (2003).

    Article  Google Scholar 

  3. Vallis, G. K. Atmospheric and Oceanic Fluid Dynamics: Fundamentals and Large-Scale Circulation (Cambridge University Press, Cambridge, UK, 2006).

    Book  Google Scholar 

  4. Meehl, G. A. et al. in Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (eds Solomon, S. et al.) (Cambridge University Press, Cambridge, UK, 2007).

    Google Scholar 

  5. Trenberth, K. E. et al. in Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (eds Solomon, S. et al.) (Cambridge University Press, Cambridge, UK, 2007).

    Google Scholar 

  6. Hudson R. D., Andrade, M. F. Follette, M. B. & Frolov A. D. The total ozone field separated into meteorological regimes – Part II: Northern Hemisphere mid-latitude total ozone trends. Atmos. Chem. Phys. 6, 5183–5191 (2006).

    Article  Google Scholar 

  7. Fu, Q., Johanson, C. M., Wallace, J. M. & T. Reichler, Enhanced mid-latitude tropospheric warming in satellite measurements. Science 312, 1179 (2006).

    Article  Google Scholar 

  8. Seidel, D. J., & Randel R. J., Recent widening of the tropical belt: Evidence from tropopause observations. J. Geophys. Res. 112, D20113 (2007).

    Article  Google Scholar 

  9. Hu, Y. & Fu, Q. Observed poleward expansion of the Hadley circulation since 1979. Atmos. Chem. Phys. 7, 5229–5236 (2007).

    Article  Google Scholar 

  10. Santer, B. D. et al. Contributions of anthropogenic and natural forcing to recent tropopause height changes. Science 301, 479–483 (2003).

    Article  Google Scholar 

  11. Seidel, D. J. & Randel, W. J. Variability and trends in the global tropopause estimated from radiosonde data. J. Geophys. Res. 111, D21101 (2006).

    Article  Google Scholar 

  12. Zhou, X. L., Geller, M. A. & Zhang, M. H. The cooling trend of the tropical cold point tropopause temperatures and its implications. J. Geophys. Res. 106, 1511–1522 (2001).

    Article  Google Scholar 

  13. Worden, J. et al. Importance of rain evaporation and continental convection in the tropical water cycle. Nature 445, 528–532 (2007).

    Article  Google Scholar 

  14. Lu, J., Vecchi, G. A. & Reichler, T. Expansion of the Hadley cell under global warming. Geophys. Res. Lett. 34, L06805 (2007).

    Google Scholar 

  15. Lau, N.-C., Leetmaa, A. & Nath, M. J. Attribution of atmospheric variations in the 1997–2003 period to SST anomalies in the Pacific and Indian Ocean basins. J. Climate 19, 3607–3628 (2006).

    Article  Google Scholar 

  16. Frierson, D., Lu, J. & Chen, G. The width of the Hadley cell in simple and comprehensive general circulation models. Geophys. Res. Lett. 34, L18804 (2007).

    Article  Google Scholar 

  17. Williams, G. P. Circulation sensitivity to tropopause height. J. Atmos. Sci. 63, 1954–1961 (2006).

    Article  Google Scholar 

  18. Lorenz, D. J. & DeWeaver, E. T. Tropopause height and zonal wind response to global warming in the IPCC scenario integrations. J. Geophys. Res. 112, D10119 (2007).

    Article  Google Scholar 

  19. Held, I. M. & Hou, A. Y. Nonlinear axially symmetric circulations in a nearly inviscid atmosphere. J. Atmos. Sci. 37, 515–533 (1980).

    Article  Google Scholar 

  20. Taguchi, M. & Hartmann, D. L. Increased occurrence of stratospheric sudden warmings during El Nino as simulated by WACCM. J. Climate 19, 324–332 (2006).

    Article  Google Scholar 

  21. Walker, C. C. & Schneider, T. Eddy influences on Hadley circulations: Simulations with an idealized GCM. J. Atmos. Sci. 63, 3333–3350 (2006).

    Article  Google Scholar 

  22. Seager, R. et al. Model projections of an imminent transition to a more arid climate in southwestern North America. Science 316, 1181–1184 (2007).

    Article  Google Scholar 

  23. Forster, P. M. de F. & Shine K. P. Assessing the climate impact of trends in stratospheric water vapor. Geophys. Res. Lett. 29, 1086 (2002).

    Article  Google Scholar 

  24. Kirk-Davidoff, D. B., Hintsa, E. J., Anderson, J. G. & Keith, D. W. The effect of climate change on ozone depletion through changes in stratospheric water vapour. Nature 402, 399–401 (1999).

    Article  Google Scholar 

  25. Lovelock, J. E. The Revenge of Gaia: Why the Earth Is Fighting Back — and How We Can Still Save Humanity (Allen Lane, London, 2006).

    Google Scholar 

  26. Kushner, P. J., Held, I. M. & Delworth, T. L. Southern Hemisphere atmospheric circulation response to global warming. J. Climate 14, 2238–2249 (2001).

    Article  Google Scholar 

  27. Polvani, L. M. & Kushner, P. J. Tropospheric response to stratospheric perturbations in a relatively simple general circulation model. Geophys. Res. Lett. 29 (2002).

  28. Haigh, J. D., Blackburn, M. & Day, R. The response of tropospheric circulation to perturbations in lower-stratospheric temperature. J. Climate 18, 3672–3685 (2005).

    Article  Google Scholar 

  29. Yin, J. H. A consistent poleward shift of the storm tracks in simulations of 21st century climate. Geophys. Res. Lett. 32, L18701 (2005).

    Article  Google Scholar 

  30. Bengtsson, L., Hodges, K. I. & Roeckner, E. Storm tracks and climate change. J. Climate 19, 3518–3543 (2006).

    Article  Google Scholar 

  31. Gillett, N. P. Northern hemisphere circulation. Nature 437, 496 (2005).

    Article  Google Scholar 

Download references

Acknowledgements

We thank Celeste Johanson (University of Washington) for providing analysis of tropical widening trends in climate model simulations for the twenty-first century. The National Center for Atmospheric Research is sponsored by the US National Science Foundation. T.J.R. was supported by NSF grant ATM0532280 and by NOAA grant NA06OAR4310148. Q.F. is supported by NOAA Grant NA17RJ1232.

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Correspondence to Dian J. Seidel.

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Seidel, D., Fu, Q., Randel, W. et al. Widening of the tropical belt in a changing climate. Nature Geosci 1, 21–24 (2008). https://doi.org/10.1038/ngeo.2007.38

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