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Enso's Non-stationary and Non-gaussian Character: the Role of Climate Shifts : Volume 16, Issue 4 (06/07/2009)

By Boucharel, J.

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Book Id: WPLBN0003986931
Format Type: PDF Article :
File Size: Pages 21
Reproduction Date: 2015

Title: Enso's Non-stationary and Non-gaussian Character: the Role of Climate Shifts : Volume 16, Issue 4 (06/07/2009)  
Author: Boucharel, J.
Volume: Vol. 16, Issue 4
Language: English
Subject: Science, Nonlinear, Processes
Collections: Periodicals: Journal and Magazine Collection (Contemporary), Copernicus GmbH
Publication Date:
Publisher: Copernicus Gmbh, Göttingen, Germany
Member Page: Copernicus Publications


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Penhoat, Y. D., Garel, B., Dewitte, B., & Boucharel, J. (2009). Enso's Non-stationary and Non-gaussian Character: the Role of Climate Shifts : Volume 16, Issue 4 (06/07/2009). Retrieved from

Description: Université de Toulouse, UPS, LEGOS, 14 Av, Edouard Belin, 31400 Toulouse, France. El Niño Southern Oscillation (ENSO) is the dominant mode of climate variability in the Pacific, having socio-economic impacts on surrounding regions. ENSO exhibits significant modulation on decadal to inter-decadal time scales which is related to changes in its characteristics (onset, amplitude, frequency, propagation, and predictability). Some of these characteristics tend to be overlooked in ENSO studies, such as its asymmetry (the number and amplitude of warm and cold events are not equal) and the deviation of its statistics from those of the Gaussian distribution. These properties could be related to the ability of the current generation of coupled models to predict ENSO and its modulation.

Here, ENSO's non-Gaussian nature and asymmetry are diagnosed from in situ data and a variety of models (from intermediate complexity models to full-physics coupled general circulation models (CGCMs)) using robust statistical tools initially designed for financial mathematics studies. In particular α-stable laws are used as theoretical background material to measure (and quantify) the non-Gaussian character of ENSO time series and to estimate the skill of ``naïve'' statistical models in producing deviation from Gaussian laws and asymmetry. The former are based on non-stationary processes dominated by abrupt changes in mean state and empirical variance. It is shown that the α-stable character of ENSO may result from the presence of climate shifts in the time series. Also, cool (warm) periods are associated with ENSO statistics having a stronger (weaker) tendency towards Gaussianity and lower (greater) asymmetry. This supports the hypothesis of ENSO being rectified by changes in mean state through nonlinear processes. The relationship between changes in mean state and nonlinearity (skewness) is further investigated both in the Zebiak and Cane (1987)'s model and the models of the Intergovernmental Panel for Climate Change (IPCC). Whereas there is a clear relationship in all models between ENSO asymmetry (as measured by skewness or nonlinear advection) and changes in mean state, they exhibit a variety of behaviour with regard to α-stability. This suggests that the dynamics associated with climate shifts and the occurrence of extreme events involve higher-order statistical moments that cannot be accounted for solely by nonlinear advection.

ENSO's non-stationary and non-Gaussian character: the role of climate shifts

Chen, D., Cane, M. A., Kaplan, A., Zebiak, S. E., and Huang, D: Predictability of El Niño over the past 148 years, Nature, 428, 733–736, 2004.; An, S.-I.: Interdecadal changes in the El Nino-La Nina asymmetry, Geophys. Res. Lett., 31, L23210, doi:101029/2004GL021299, 2004.; An, S.-I. and Jin, F. F.: Nonlinearity and asymmetry of ENSO, J. Climate, 17, 2399–2412, 2004.; An, S.-I., Hsieh, W. W., and Jin F.-F.: A nonlinear analysis of ENSO cycle and its interdecadal changes, J. Climate, 18, 3229–3239, 2005.; An, S.-I. : A review on interdecadal changes in the nonlinearity of the El Niño-Southern Oscillation, Theor. Appl. Climatol., 97, 29–40, 2009.; Belmadani, A., Dewitte, B., and An, S.-I.: ENSO feedbacks and variability time scales in a multi-model ensemble, J. Climate, revised, 2009.; Burgers, G. and Stephenson, D. B.: The Normality of El Niño, Geophys. Res. Lett., 26, 8, 1027–1039, 1999.; Capotondi, A., Wittenberg, A., and Masina, S.: Spatial and temporal structure of tropical Pacific interannual variability in 20th century coupled simulations, Ocean Model., 15, 274–298, 2006.; Carton, J. A. and Giese, B. S.: SODA: A Reanalysis of Ocean Climate, Mon. Weather Rev., 136, 2999–3017, 2008.; Chambers, J. M., Mallows C. L., and Stuck B. W.: A method for simulating stable random variables, J. Am. Stat. Assoc., 71, 340–344, 1976.; d'Estampes, L.: Traitement statistique des processus alpha stables. Mesure de dépendances et identification des AR stables Thèse de l'Institut National Polytechnique de Toulouse, 125 pp., 2003.; Dewitte B.: Sensitivity of an intermediate coupled ocean-atmosphere model of the tropical Pacific to its oceanic vertical structure, J. Climate, 13, 2363–2388, 2000.; Jin, F.-F., An, S.I., Timmermann, A., and Zhao, J.: Strong El Niño events and nonlinear dynamical heating, Geophys. Res. Lett., 30, doi:10.1029/2002GL016356, 2003.; Dewitte, B., Yeh, S.-W., Moon, B.-K., Cibot, C., and Terray, L.: Rectification of ENSO variability by interdecadal changes in the equatorial background mean state in a CGCM simulation, J. Climate, 20, 2002–2021, 2007a.; Dewitte, B., Cibot, C., Périgaud, C., An, S.-I., and Terray, L.: Interaction between near-annual and ENSO modes in a CGCM simulation: Role of the equatorial background mean state, J. Climate, 20, 1035–1052, 2007b.; Fedorov, A. V. and Philander, S. G.: Is El Niño changing?, Science, 288, 5473, 1997–2002, 2000.; Feller, W.: An introduction to probability theory and its applications, 2. Wiley, New York, ,626 pp., 1966.; Gnedenko, V. B. and Kolmogorov, A. N. : Limit distributions for sums of random variables, Addison-Wesley, 293, 1954.; Granger, C. W. and Orr, D.: Infinite Variance and research strategy in time series analysis, J. Am. Stat. Assoc., 67, 275–285, 1972.; Gu, D. and Philander S. G.: Interdecadal climate fluctuations that depend on exchanges between the tropics and extra-tropics, Science, 275, 5301, 805–807, 1997; Guilderson, T. P. and Schrag D. P.: Abrupt shift in subsurface temperatures in the tropical pacific associated with changes in El Niño, Science, 281, 5374, 240–243, 1998.; Guilyardi, E.: El Niño-mean state-seasonal cycle interactions in a multi model ensemble, Clim. Dynam., 26(3), 329–348, 2006.; Hald, A.: A History of Probability and Statistics and their applications before 1750, New York: Wiley. Chapter 7, John Graunt and the Observations upon the Bills of Mortality, 1662, 1990.; Hannachi, A., Stephenson, D. B., and Sperber, K. R.: Probability-based methods for quantifying nonlinearity in the ENSO, Clim. Dynam., 22, 69–70, 2004.; Hannachi, A.: Quantifying changes and their uncertainties in probability distribution of climate variables using robust statistics, Clim. Dynam., 27, 301–317, 2006.; Kaplan, A., Cane, M., Kushnir, Y., Clement, A., Blumenthal, M., and Rajagopalan, B.: Analyses of global sea surface temperature 1856–1991, J. Geophys. Res., 103, 18, 567–589, 1998.; Karspeck, A. R., Seager, R., and Cane M. A.: Predictability of tropical Pacific decad


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