Comment on 'Influence of the Southern Oscillation on tropospheric temperature' by J. D. McLean, C. R. de Freitas, and R. M. Carter

摘要

We demonstrate an alternative correlation between the El Ni\~no SouthernOscillation (ENSO) and global temperature variation to that shown by McLean etal. [2009]. We show 50% of the variation in RATPAC-A tropospheric temperature(and 54% of HadCRUT3) is explained by a novel cumulative Southern OscillationIndex (cSOI) term in a simple linear regression. We review evidence fromphysical and statistical research in support of the hypothesis thataccumulation of the effects of ENSO can produce natural multi-decadal warmingtrends. Although it is not possible to reliably determine the relativecontribution of anthropogenic forcing and SOI accumulation from multipleregression models due to collinearity, these analyses suggest that anaccumulation ratio cSOI/SOI of $4.8\pm1.5%$ and up to $9\pm2%$ is sufficientfor ENSO to play a large part in the global mean temperature trend since 1960.