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How may tropical cyclones change in a warmer climate?

By Lennart Bengtsson, K. I. Hodges, M. Esch, N. Keenlyside, L. Kornblueh, J.-J. Luo and T. Yamagata


Tropical Cyclones (TC) under different climate conditions in the Northern Hemisphere have been investigated with the Max Planck Institute (MPI) coupled (ECHAM5/MPIOM) and atmosphere (ECHAM5) climate models. The intensity and size of the TC depend crucially on resolution with higher wind speed and smaller scales at the higher resolutions. The typical size of the TC is reduced by a factor of 2.3 from T63 to T319 using the distance of the maximum wind speed from the centre of the storm as a measure. The full three dimensional structure of the storms becomes increasingly more realistic as the resolution is increased. For the T63 resolution, three ensemble runs are explored for the period 1860 until 2100 using the IPCC SRES scenario A1B and evaluated for three 30 year periods at the end of the 19th, 20th and 21st century, respectively. While there is no significant change between the 19th and the 20th century, there is a considerable reduction in the number of the TC by some 20% in the 21st century, but no change in the number of the more intense storms. Reduction in the number of storms occurs in all regions. A single additional experiment at T213 resolution was run for the two latter 30-year periods. The T213 is an atmospheric only experiment using the transient Sea Surface Temperatures (SST) of the T63 resolution experiment. Also in this case, there is a reduction by some 10% in the number of simulated TC in the 21st century compared to the 20th century but a marked increase in the number of intense storms. The number of storms with maximum wind speeds greater than 50ms-1 increases by a third. Most of the intensification takes place in 2 the Eastern Pacific and in the Atlantic where also the number of storms more or less stays the same. We identify two competing processes effecting TC in a warmer climate. First, the increase in the static stability and the reduced vertical circulation is suggested to contribute to the reduction in the number of storms. Second, the increase in temperature and water vapor provide more energy for the storms so that when favorable conditions occur, the higher SST and higher specific humidity will contribute to more intense storms. As the maximum intensity depends crucially on resolution, this will require higher resolution to have its full effect. The distribution of storms between different regions does not, at first approximation, depend on the temperature itself but on the distribution of the SST anomalies and their influence on the atmospheric circulation. Two additional transient experiments at T319 resolution where run for 20 years at the end of the 20th and 21st century, respectively using the same conditions as in the T213 experiments. The results are consistent with the T213 study. The total number of tropical cyclones were similar to the T213 experiment but were generally more intense. The change from the 20th to the 21st century was also similar with fewer TC in total but with more intense cyclones

Topics: 551
Publisher: Wiley-Blackwell
Year: 2007
OAI identifier: oai:centaur.reading.ac.uk:189

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  3. (2004). Adaptive grids for weather and climate models, doi
  4. (2001). African Easterly Wave Variability and its Relationship to Atlantic Tropical Cyclone Activity,
  5. (1996). AMIP II guidelines. Atmospheric Model Intercomparison Project Newsletter, No. 8, AMIP Project Office,
  6. (2006). An assessment of climate feedbacks in coupled oceanatmosphere models.
  7. (1992). An Introduction to Dynamical Meteorology,
  8. (1990). Can existing climate models be used to study anthropogenic changes in tropical cyclone climate?
  9. (2006). Can we detect trends in extreme tropical cyclones?
  10. (2005). Changes in atmospheric sulfur burdens and concentrations and resulting radiative forcings under IPCC SRES emission scenarios for 1990-2100.
  11. (2005). Changes in Tropical Cyclone Number, Duration, and Intensity in a Warming Environment. doi
  12. (2001). Climate Change 2001: The Scientific Basis, Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel of Climate Change. doi
  13. (2006). Climate projections for the 21st century. Max Planck Institute for Meteorology, Internal Report, 28 pp [available from Max Planck Institute for Meteorology,
  14. (2006). Comments on “Changes in Tropical Cyclone Number, Duration, and Intensity in a Warming Environment”,
  15. (1998). Dissipative heating and hurricane intensity.
  16. (2005). El Niño in a changing climate: a multi-model study,
  17. (2004). ENSO influence on Atlantic hurricanes via tropospheric warming,
  18. (1980). Finite Rotations.
  19. (2006). Hurricane forecasts with a global mesoscale-resolving model: Preliminary results with Hurricane Katrina
  20. (2007). Hurricane type vortices in a highresolution global model: Comparison with observations and Re-Analyses, Tellus, 59A,
  21. (1995). Hurricane-type vortices in a general circulation model.
  22. (1979). Hurricanes: Their formation, structure and likely role in the tropical circulation” in Meteorology Over Tropical Oceans.
  23. (2005). Increasing destructiveness of tropical cyclones over the past 30 years.
  24. (2002). Influence of the global warming on tropical cyclone climatology: An experiment with the JMA global model.
  25. (2000). IPCC Special Report on Emissions Scenarios.
  26. (2006). Low frequency variability in globally integrated tropical cyclone power dissipation,
  27. M.Vanicek, T.Ansell and S.F.B.Tett, 2006: Improved analyses of changes and uncertainties in sea surface temperature measured in situ since the mid-nineteenth century: the HadSST2 data set.
  28. (2006). Objectively-determined resolution-dependent threshold criteria for the detection of tropical cyclones in climate models and reanalyses,
  29. (1948). On the formation and structure of tropical cyclones,
  30. (2006). Response of hurricane-type vortices to global warming as simulated by ARPEGE-Climat at high resolution,
  31. (2006). Robust Responses of the Hydrological Cycle to Global Warming.
  32. (1995). Seasonal and interannual variability of tropical cyclogenesis: Diagnostics from large-scale fields.
  33. (2006). Storm Tracks and Climate Change,
  34. (1987). The dependence of hurricane intensity on climate.
  35. (2005). The Hurricane Intensity Issue.
  36. (1988). The maximum intensity of hurricanes.
  37. (1997). The maximum potential intensity of tropical cyclones.
  38. (1977). The structure and energetics of the tropical cyclone I. Storm structure,
  39. (2006). Tropical Cyclone Climatology in a Global-Warming Climate as Simulated in a 20 kmMesh Global Atmospheric Model: Frequency and Wind Intensity Analysis.
  40. (1992). Tropical cyclone frequencies inferred from Gray’s yearly genesis parameter: Validation of GCM tropical climate.
  41. (2006). Tropical intraseasonal variability in 14 IPCC AR4 climate models. Part I: Convective signals.
  42. (1996). Will greenhouse gas-induced warming over the next 50 years lead to higher frequency and greater intensity of hurricanes?

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