This is figure 3 from:
Wilson, I.R.G., 2013, Are Global Mean Temperatures Significantly Affected by Long-Term Lunar Atmospheric Tides? Energy & Environment, Vol 24, No. 3 & 4, pp. 497 – 508.
The Extended Multivariate ENSO index (MEI) is the un-rotated, first principal component of the MSLP (HadSLP2)  and SST (HadSST2)  over the tropical Pacific . As with the Niño3.4 index, negative values of the MEI represent the La Niña ENSO phase, while positive values of the MEI represent the El Niño ENSO phase .
The green curve in figure 3 shows the annual global HadCRUT3 combined land and sea-surface temperature anomalies between 1879 and 2006 [22,23]. This curve has been arbitrarily scaled for the purpose of ready comparison with the blue and red curves giving the MEI index.
Superimposed on these curves are vertical lines delineate four 30 year periods of alternating cooling and warming, starting in the years 1887, 1917, 1947, and 1977. In addition, red straight lines have been drawn upon the green temperature anomaly curve showing the approximate temperature gradient for each of the four climate epochs.
The dotted red curve gives the extended MEI index integrated over four separate 30-year climate epochs starting in the years 1880, 1910, 1940, and 1970. If these starting years are used, the cumulative MEI indices change sign (from + to – and reverse) in three out of the four climate epochs. However, if the starting year for each epoch is shifted forward seven years to 1887, 1917, 1947 and 1977 (dark blue curve), then the cumulative MEI indices do not change sign during each of the climate epochs.
What figure 3 is telling us is that whenever the relative strength and/or frequency of the El Niño events are greater than that of the La Niña events (i.e. the cumulative MEI is trending positive) then global mean temperatures increase, and that whenever the relative strength and/or frequency of the La Niña events are greater than that of the El Niño events (i.e. the cumulative MEI is trending negative) then global mean temperature decreases.
Hence, I believe that figure 3 supports the claims made by Wilson , Tisdale, and the subsequent claims of de Freitas and McLean .
. Tisdale R., Who turned up the heat? – The unsuspecting global-warming culprit – El Niño-Southern Oscillation, 2012
. http://astroclimateconnection.blogspot.com/2011/12/world-mean-temperature-warmscools.html, Last accessed 24/01/2019
. de Freitas, C.R. and McLean, J.D., Update of the chronology of natural signals in the near-surface mean global temperature record and the Southern Oscillation Index, International Journal of Geosciences, 2013, 4(1), 234-239.
. Rayner N.A., et al., Improved analyses of changes and uncertainties in sea surface temperature measured in situ since the mid-nineteenth century: the HadSST2 data set, J. Climate. 2006, 19(3), 446-469.
. Allan R.J. and Ansell T., A new globally complete monthly historical gridded mean sea level pressure dataset (HadSLP2): 1850-2004. J. Climate, 2006, 19, 5816-5842.
. Wolter K. and Timlin M. S., El Niño/Southern Oscillation behavior since 1871 as diagnosed in an extended multivariate ENSO index (MEI.ext). Intl. J. Climatology, 2011, 31, 14pp., in press. Available from Wiley Online Library.
. Brohan P., Kennedy J.J., Harris I., Tett S.F.B., and Jones P.D., Uncertainty estimates in regional and global observed temperature changes: a new dataset from 1850. J. Geophysical Research, 2006, 111, D12106
. http://www.cru.uea.ac.uk/cru/data/temperature/ – Last accessed: 07/11/12
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