An objective analysis of the evidence for global warming suggests little if any anthropogenic effect, consistent with a direct radiative effect from increased CO2. It is also obvious that global temperature and ocean heat content should be related, so it’s somewhat surprising to see OHC rising so fast around 2002-3 when ocean temperature is relatively stable (upper line below).
Also given the known issues with this data set, it’s bizarre to see top bureaucrats and scientists like Wong/Steffen placing so much importance on the trajectory of OHC over a short run since 2000. This is reminiscent of the missplaced importance the Garnaut commission placed on the now discredited ‘worse than we thought’ finding of Rahmstorf and others, that he has admitted was an error.
At the suggestion of cohenite, I plotted the distribution of changes in the OHC data (above), at lags of one, two, three and four years. These changes have been normalized to a mean of zero and the x-axis is the standard deviation. The changes in the OHC around 2002-3 stand out, particularly at lag 2 and 3, as 3-sigma events. That is, the probability of a change in OHC of this magnitude is around 0.001, or there is a high probability that this jump is an outlier, and due to some problem in the data.
The above-the-fold figure illustrates the effect of treating one, and then two years changes as outliers in this type of data. Because of the high autocorrelation, removal of a step up affects all subsequent points, and they all get shifted down. The result is still a slightly increasing OHC, but far less alarming that the impression given previously.
Obviously this does not prove the data are in error. But people remove 3-sigma data points all the time, particularly when caution over possible instrumental errors is called for, as could be the case with the ARGO floats here. Does anyone else feel uncomfortable with so-called leaders incapacity to distinguish preliminary results, and using them for self-serving purposes?