Extended Data Fig. 6: 21st century Niño3.4 variability change (oC) and nonlinear Bjerknes feedback represented by Niño3 SST skewness.
From: Increased ENSO sea surface temperature variability under four IPCC emission scenarios
Shown are for the SSP585 emission scenario, a, based on monthly value, and b, based on ENSO peak season of December, January, and February (DJF). Observed skewness based on 1900–2020 from a reanalysis26 is shown as a black solid vertical line in each panel. Correlation coefficient and the P-value are shown in each panel, indicating statistically significant relationships above the 99% significance level. SST skewness in the eastern equatorial Pacific is an integral component of a parameter that also encapsulates skewness in the central Pacific to depict ENSO nonlinearity as a whole7,10. In terms of this nonlinearity parameter, a larger number of CMIP6 (79%) than CMIP5 (55%) models simulate greater than one third of the observed parameter.
