Validation of Numerical Climate Models for the El Niño-Southern Oscillation System

Abstract

Statistical properties of the observed bi-variate ENSO time series (sea surface temperature within the Niño area 3.4 and the Southern Oscillation Index) from 1876 through 2005 are compared with respective properties of 46 CMIP5 models used in the historical experiment, one run per model. The models were found to exaggerate linear trend rates of SST; mean value and variance estimates have a large scatter, most probability densities are Gaussian, the shape of spectra is reproduced correctly in most cases though the spectra of simulated Southern Oscillation have a negative bias. Most estimates of coherence correctly reproduce the behavior of coherence between the observed SST and SOI that exceeds 0.9 at moderate frequencies. The average coherent spectrum of simulated SST is close to the “observed” coherent spectrum and has a negative bias in the SOI case. The results for the time domain require improvement; the frequency domain results are satisfactory.

Keywords

climate model validation coherence and coherent spectra El Niño-Southern Oscillation

References

Rao

Achuta K.

and Sperber

K. R.

(2006) “ENSO simulation in coupled ocean-atmosphere models: Are the current models better?” Climate Dynamics, Vol. 27(1), pp. 1–15.

Alexander

M.A.

Bladé

Newman

Lanzante

J.R.

Lau

N.-C.

and Scott

J.D.

, 2002. “The Atmospheric Bridge: The Influence of ENSO Teleconnections on Air–Sea Interaction over the Global Oceans.” J. Climate, Vol. 15(16), pp. 2205–2231.

Bendat

and Piersol

2010. “Random Data. Analysis and Measurements Procedures”, John Wiley & Sons, Hoboken, New Jersey.

Box

G.E.P.

Jenkins

G.W.

and Reinsel

G.C.

, 1994. “Time Series Analysis. Forecasting and Control”, Third Edition. Prentice-Hall, New Jersey.

Bartholomew

and Jin

M.S.

, 2013. “ENSO Effects on Land Skin Temperature Variations: A Global Study from Satellite Remote Sensing and NCEP/NCAR Reanalysis”, Climate, Vol. 1(2), pp. 53–73.

Cibot

Maisonnave

Terray

Dewitte

, 2005. “Mechanisms of tropical Pacific interannual-to- decadal variability in the ARPEGE/ORCA global coupled model.” Climate Dynamics, Vol. 24(7–8), pp. 823–842

Chu

P.-S.

and Katz

R.W.

, 1985. “Spectral estimation from time series models with relevance to the Southern Oscillation”. J. Climate, Vol. 2(1), pp. 86–90.

D'Agostino

R.D.

and Pearson

E.S.

, 1973. “Tests for departure from normality. Empirical results for the distribution of b₂ and ÷b₁.” Biometrika, Vol. 60(3), pp. 613–622.

Guilyardi

Bellenger

Collins

Ferrett

Cai

and Wittenberg

2012. “A first look at ENSO in CMIP5.” CLIVAR Exchanges No. 58, Vol. 17(1), pp. 29–32.

10.

Jin

F.-F.

1997. “An equatorial ocean recharge paradigm. Part I: Conceptual model”, J. Atmos. Sci., Vol. 54(7), pp. 811–829.

11.

Kleeman

2011. “Spectral analysis of multidimensional stochastic geophysical models with an application to decadal ENSO variability”, J. Atmos. Sci., Vol. 68(1), pp. 13–25.

12.

Lin

J-L.

2007. “Interdecadal variability of ENSO in 21 IPCC AR4 coupled GCMs”, Geophys. Res. Letters, Vol. 34(12), L12702, doi:10.1029/2006GL028937.

13.

Mokhov

Khvorostyanov

Eliseev

2004. “Decadal and longer term changes in El Niño – Southern Oscillation characteristics”, Intern. J. Climatology, 24(4), pp. 401–414.

14.

Philander

S. G.

1989. “El Niño, La Niña, and the Southern Oscillation”, Academic Press, CA.

15.

Privalsky

Protsenko

and Fogel

1987. “The sampling variability of autoregressive spectral estimates for bi-variate hydrometeorological processes”, Proc. 1^st World Congress of the Bernoulli Society on Mathematical Stat. Theory and Applications, Tashkent, USSR, Vol. 2, pp. 651–654 VNU Science Press, Utrecht.

16.

Privalsky

1999. “Parametric model; order selection”, Probability and Mathematical Statistics Encyclopedia. Prokhorov

Yu. V.

(ed.), The Great Russian Encyclopedia Publishers, Moscow, Russia, 442–443 (in Russian).

17.

Privalsky

Muzylev

2013. “An Experimental Stochastic Model of the El Niño – Southern Oscillation System at Climatic Time Scales”, Universal Journal of Geoscience, Vol. 1(1), pp. 28–36

18.

Van Oldenborgh

G.J.

Philip

S.Y.

and Collins

2005. “El Niño in a changing climate: A multi-model study”, Ocean Science Vol. 1(2), pp. 81–95.

19.

Von Storch

J.-S.

Wang

and Wang

2001. “The ENSO-spectrum: A result of deterministic chaos or stochastic forcing?”, Dynamics of Atmospheric and Oceanic Circulation and Climate, China Meteorological Press, Beijing, pp. 579–600.

20.

Yaglom

A.M.

1962. “An Introduction to the Theory of Stationary Random Functions”, Dover Publications, NY.