Impact of Different ENSO Regimes on Southwest Pacific Tropical Cyclones

Savin S. Chand Centre for Australian Weather and Climate Research, Bureau of Meteorology, Melbourne, Victoria, Australia

Search for other papers by Savin S. Chand in
Current site
Google Scholar
PubMed
Close
,
John L. McBride Centre for Australian Weather and Climate Research, Bureau of Meteorology, Melbourne, Victoria, Australia

Search for other papers by John L. McBride in
Current site
Google Scholar
PubMed
Close
,
Kevin J. Tory Centre for Australian Weather and Climate Research, Bureau of Meteorology, Melbourne, Victoria, Australia

Search for other papers by Kevin J. Tory in
Current site
Google Scholar
PubMed
Close
,
Matthew C. Wheeler Centre for Australian Weather and Climate Research, Bureau of Meteorology, Melbourne, Victoria, Australia

Search for other papers by Matthew C. Wheeler in
Current site
Google Scholar
PubMed
Close
, and
Kevin J. E. Walsh School of Earth Sciences, University of Melbourne, Parkville, Victoria, Australia

Search for other papers by Kevin J. E. Walsh in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

The influence of different types of ENSO on tropical cyclone (TC) interannual variability in the central southwest Pacific region (5°–25°S, 170°E–170°W) is investigated. Using empirical orthogonal function analysis and an agglomerative hierarchical clustering of early tropical cyclone season Pacific sea surface temperature, years are classified into four separate regimes (i.e., canonical El Niño, canonical La Niña, positive-neutral, and negative-neutral) for the period between 1970 and 2009. These regimes are found to have a large impact on TC genesis over the central southwest Pacific region. Both the canonical El Niño and the positive-neutral years have increased numbers of cyclones, with an average of 4.3 yr−1 for positive-neutral and 4 yr−1 for canonical El Niño. In contrast, during a La Niña and negative-neutral events, substantially fewer TCs (averages of ~2.2 and 2.4 yr−1, respectively) are observed in the central southwest Pacific. The enhancement of TC numbers in both canonical El Niño and positive-neutral years is associated with the extension of favorable low-level cyclonic relative vorticity, and low vertical wind shear eastward across the date line. Relative humidity and SST are also very conducive for genesis in this region during canonical El Niño and positive-neutral events. The patterns are quite different, however, with the favorable conditions concentrated in the date line region for the positive-neutral, as compared with conditions farther eastward for the canonical El Niño regime. A significant result of the study is the demonstration that ENSO-neutral events can be objectively clustered into two separate regimes, each with very different impacts on TC genesis.

Corresponding author address: Savin S. Chand, Centre for Australian Weather and Climate Research, GPO Box 1289, Melbourne VIC 3001, Australia. E-mail: schand@bom.gov.au

Abstract

The influence of different types of ENSO on tropical cyclone (TC) interannual variability in the central southwest Pacific region (5°–25°S, 170°E–170°W) is investigated. Using empirical orthogonal function analysis and an agglomerative hierarchical clustering of early tropical cyclone season Pacific sea surface temperature, years are classified into four separate regimes (i.e., canonical El Niño, canonical La Niña, positive-neutral, and negative-neutral) for the period between 1970 and 2009. These regimes are found to have a large impact on TC genesis over the central southwest Pacific region. Both the canonical El Niño and the positive-neutral years have increased numbers of cyclones, with an average of 4.3 yr−1 for positive-neutral and 4 yr−1 for canonical El Niño. In contrast, during a La Niña and negative-neutral events, substantially fewer TCs (averages of ~2.2 and 2.4 yr−1, respectively) are observed in the central southwest Pacific. The enhancement of TC numbers in both canonical El Niño and positive-neutral years is associated with the extension of favorable low-level cyclonic relative vorticity, and low vertical wind shear eastward across the date line. Relative humidity and SST are also very conducive for genesis in this region during canonical El Niño and positive-neutral events. The patterns are quite different, however, with the favorable conditions concentrated in the date line region for the positive-neutral, as compared with conditions farther eastward for the canonical El Niño regime. A significant result of the study is the demonstration that ENSO-neutral events can be objectively clustered into two separate regimes, each with very different impacts on TC genesis.

Corresponding author address: Savin S. Chand, Centre for Australian Weather and Climate Research, GPO Box 1289, Melbourne VIC 3001, Australia. E-mail: schand@bom.gov.au
Save
  • Ashok, K., S. K. Behera, S. A. Rao, H. Weng, and T. Yamagata, 2007: El Niño Modoki and its possible teleconnection. J. Geophys. Res., 112, C11007, doi:10.1029/2006JC003798.

    • Search Google Scholar
    • Export Citation
  • Basher, R. E., and X. Zheng, 1995: Tropical cyclones in the southwest Pacific: Spatial patterns and relationships to Southern Oscillation and sea surface temperature. J. Climate, 8, 12491260.

    • Search Google Scholar
    • Export Citation
  • Camargo, S. J., A. H. Sobel, A. G. Barnston, and J. K. Philip, 2010: The influence of natural climate variability on tropical cyclones, and seasonal forecasts of tropical cyclone activity. Global Perspectives on Tropical Cyclones: From Science to Mitigation, J. C. L. Chan and J. D. Kepert, Eds., World Scientific, 325–360.

  • Chand, S. S., and K. J. E. Walsh, 2009: Tropical cyclone activity in the Fiji region: Spatial patterns and relationship to large-scale circulation. J. Climate, 22, 38773893.

    • Search Google Scholar
    • Export Citation
  • Chand, S. S., and K. J. E. Walsh, 2011: Influence of ENSO on tropical cyclone intensity in the Fiji region. J. Climate, 24, 40964108.

    • Search Google Scholar
    • Export Citation
  • Chand, S. S., K. J. E. Walsh, and J. C. L. Chan, 2010: A Bayesian regression approach to seasonal prediction of tropical cyclones affecting the Fiji region. J. Climate, 23, 34253445.

    • Search Google Scholar
    • Export Citation
  • Chen, G., 2011: How does shifting Pacific Ocean warming modulate on tropical cyclone frequency over the South China Sea? J. Climate, 24, 46954700.

    • Search Google Scholar
    • Export Citation
  • Chen, G., and C. Y. Tam, 2010: Different impacts of two kinds of Pacific Ocean warming on tropical cyclone frequency over the western North Pacific. Geophys. Res. Lett., 37, L01803, doi:10.1029/2009GL041708.

    • Search Google Scholar
    • Export Citation
  • Chu, P. S., and J. Wang, 1997: Tropical cyclone occurrences in the vicinity of Hawaii: Are the differences between El Niño and non–El Niño years significant? J. Climate, 10, 26832689.

    • Search Google Scholar
    • Export Citation
  • Emery, W. J., and R. E. Thomson, 2001: Data Analysis Methods in Physical Oceanography. 2nd ed. Elsevier, 634 pp.

  • Evans, J. L., and R. J. Allan, 1992: El Niño/Southern Oscillation modification to the structure of the monsoon and tropical cyclone activity in the Australasian region. Int. J. Climatol., 12, 611623.

    • Search Google Scholar
    • Export Citation
  • Hong, C.-C., Y.-H. Li, T. Li, and M.-Y. Lee, 2011: Impacts of central Pacific and eastern Pacific El Niños on tropical cyclone tracks over the western North Pacific. Geophys. Res. Lett., 38, L16712, doi:10.1029/2011GL048821.

    • Search Google Scholar
    • Export Citation
  • Kalnay, E., and Coauthors, 1996: The NCEP/NCAR 40-Year Reanalysis Project. Bull. Amer. Meteor. Soc., 77, 437471.

  • Kao, H.-Y., and J.-Y. Yu, 2009: Contrasting eastern-Pacific and central-Pacific types of ENSO. J. Climate, 22, 615632.

  • Kim, H.-M., P. J. Webster, and J. A. Curry, 2009: Impact of shifting patterns of Pacific Ocean warming on North Atlantic tropical cyclones. Science, 325, 7780.

    • Search Google Scholar
    • Export Citation
  • Kim, H.-M., P. J. Webster, and J. A. Curry, 2011: Modulation of North Pacific tropical cyclone activity by three phases of ENSO. J. Climate, 24, 18391849.

    • Search Google Scholar
    • Export Citation
  • Kug, J.-S., F.-F. Jin, and S.-I. An, 2009: Two types of El Niño events: Cold tongue El Niño and warm pool El Niño. J. Climate, 22, 14991515.

    • Search Google Scholar
    • Export Citation
  • Kuleshov, Y., L. Qi, R. Fawcett, and D. Jones, 2008: On tropical cyclone activity in the Southern Hemisphere: Trends and the ENSO connection. Geophys. Res. Lett., 35, L14S08, doi:10.1029/2007GL032983.

    • Search Google Scholar
    • Export Citation
  • Kuleshov, Y., L. Qi, R. Fawcett, and D. Jones, 2009: Improving preparedness to natural hazards: Tropical cyclone prediction for the Southern Hemisphere. Ocean Science, J. Gan, Ed., Vol. 12, Advances in Geosciences, World Scientific, 127–143.

  • Kuleshov, Y., R. Fawcett, L. Qi, B. Trewin, D. Jones, J. McBride, and H. Ramsay, 2010: Trends in tropical cyclones in the south Indian Ocean and the South Pacific Ocean. Geophys. Res. Lett., 115, D01101, doi:10.1029/2009JD012372.

    • Search Google Scholar
    • Export Citation
  • Larkin, N. K., and D. E. Harrison, 2005: Global seasonal temperature and precipitation anomalies during El Niño autumn and winter. Geophys. Res. Lett., 32, L16705, doi:10.1029/2005GL022860.

    • Search Google Scholar
    • Export Citation
  • McBride, J. L., 1995: Tropical cyclone formation. Global perspectives on tropical cyclones, R. L. Elsberry, Ed., WMO Tech. Doc. WMO/TD-693, Tropical Cyclone Programme Rep. TCP-38, 63–105.

  • McBride, J. L., M. R. Haylock, and N. Nicholls, 2003: Relationships between the Maritime Continent heat source and the El Niño–Southern Oscillation phenomenon. J. Climate, 16, 29052914.

    • Search Google Scholar
    • Export Citation
  • Nicholls, N., 1979: A possible method for predicting seasonal tropical cyclone activity in the Australian region. Mon. Wea. Rev., 107, 12211224.

    • Search Google Scholar
    • Export Citation
  • Nicholls, N., 1984: The Southern Oscillation, sea-surface temperature, and interannual fluctuations in Australian tropical cyclone activity. J. Climatol., 4, 661670.

    • Search Google Scholar
    • Export Citation
  • Ramsay, H. A., L. M. Leslie, P. J. Lamb, M. B. Richman, and M. Leplastrier, 2008: Interannual variability of tropical cyclones in the Australian region: Role of large-scale environment. J. Climate, 21, 10831103.

    • Search Google Scholar
    • Export Citation
  • Rasmusson, E. M., and T. H. Carpenter, 1982: Variations in tropical sea surface temperature and surface wind fields associated with the Southern Oscillation/El Niño. Mon. Wea. Rev., 110, 354384.

    • Search Google Scholar
    • Export Citation
  • Rayner, N. A., D. E. Parker, E. B. Horton, C. K. Folland, L. V. Alexander, D. P. Rowell, E. C. Kent, and A. Kaplan, 2003: Global analyses of sea surface temperature, sea ice, and night marine air temperature since the late nineteenth century. J. Geophys. Res., 108, 4407, doi:10.1029/2002JD002670.

    • Search Google Scholar
    • Export Citation
  • Revell, C. G., and S. W. Goulter, 1986a: Lagged relationships between Southern Oscillation and numbers of tropical cyclones in the South Pacific region. Mon. Wea. Rev., 114, 26692670.

    • Search Google Scholar
    • Export Citation
  • Revell, C. G., and S. W. Goulter, 1986b: South Pacific tropical cyclones and the Southern Oscillation. Mon. Wea. Rev., 114, 11381145.

    • Search Google Scholar
    • Export Citation
  • Singh, A., T. Delcroix, and S. Cravatte, 2011: Contrasting the flavors of El Niño-Southern Oscillation using sea surface salinity observations. J. Geophys. Res., 116, C06016, doi:10.1029/2010JC006862.

    • Search Google Scholar
    • Export Citation
  • Takahashi, K., A. Montecinos, K. Goubanova, and B. Dewitte, 2011: ENSO regimes: Reinterpreting the canonical and Modoki El Niño. Geophys. Res. Lett., 38, L10704, doi:10.1029/2011GL047364.

    • Search Google Scholar
    • Export Citation
  • Trenberth, K. E., 1997: The definition of El Niño. Bull. Amer. Meteor. Soc., 78, 27712777.

  • Trenberth, K. E., and D. P. Stepaniak, 2001: Indices of El Niño evolution. J. Climate, 14, 16971701.

  • Vincent, E. M., M. Lengaigne, C. E. Menkes, N. C. Jourdain, P. Marchesiello, and G. Madec, 2011: Interannual variability of the South Pacific convergence zone and implications for tropical cyclone genesis. Climate Dyn., 36, 18811896, doi:10.1007/s00382-009-0716-3.

    • Search Google Scholar
    • Export Citation
  • von Storch, H., and F. W. Zwiers, 1999: Statistical Analysis in Climate Research. Cambridge University Press, 484 pp.

  • Ward, J. H., 1963: Hierarchical grouping to optimize an objective function. J. Amer. Stat. Assoc., 58, 236244.

  • Wyrtki, K., 1975: El Niño—The dynamic response of the equatorial Pacific Ocean to atmospheric forcing. J. Phys. Oceanogr., 5, 572584.

    • Search Google Scholar
    • Export Citation
  • Yu, J.-Y., and S. T. Kim, 2010: Three evolution patterns of central-Pacific El Niño. Geophys. Res. Lett., 37, L08706, doi:10.1029/2010GL042810.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 464 147 9
PDF Downloads 414 138 9