So it occurred to me it should be easy to create a global temperature surface temperature index using the Berkley Earth land surface data, and the recent HADSST3 reconstruction, the only sea surface temperature index which has been corrected at all for the post World War II discontinuity. Just take the anomalies of Land Surface temperature, multiply them by fraction land area (.29) (more precisely, fraction non ocean) and add add it to HADSST3 times fraction ocean area (.71). This results in this index:
Don’t be too worried about that last datapoint shooting off like that: it’s September, because that was where BEST ended when I downloaded…I think a week ago? Anyway, it looks to me like something in the BEST algorithm results in spuriously too high or low final anomaly values, some kind of endpoint problem. It doesn’t appear in other datasets at all which pretty much verfies that it is spurious, and I have seen similar spurious final anomaly problems with BEST in the cool direction. As they update the data, they disappear to be replaced by spikes in the new latest anomaly.
Regardless, I’ve done some interesting analyses. For one thing, I’ve made some improvements to my volcanic eruption profile detection, the lag in this index is closer to seven months and the effect is ever so slightly larger. I can explain some of my newer methodology if anyone likes. At any rate, the removal of volcanic eruption effects has some interesting results. First, in the original data, it’s worthwhile to compare the trend from December 1978 (when UAH satellite anomalies begin) to the end of the data, which is currently September 2013, with the highest earlier trend of the same length in the data (which happens to be from November 1907 to August 1942):
The two trends are almost parallel, and it is doubtful the trends are statistically significantly different. But keep in mind, during the latter period there where two volcanic eruptions, in the early 80s and early 90s, while no volcanoes erupted in the earlier period. So I remove my most recent estimate of the volcanic eruption effect, which has the following result on this comparison:
Now, taking the volcanic eruptions into account, it turns out that the earlier warming was faster than the later one, albeit by an obviously negligible amount. Nevertheless, this means that a trend which most of the alarmed scientists concede was probably natural, was actually larger than the trend that is supposedly exclusively driven by anthropogenic forcing. And keep in mind again, we don’t actually know what caused the earlier warming, as even models which include larger changes in solar irradiance than probably actually occurred, and volcanoes, fail to reproduce the warming at the appropriate magnitude. So the question for people who buy the “attribution argument” is this: how do you know whatever caused the earlier warming didn’t in large part cause the late warming? Because if you don’t know, then it could have, and therefore the attribution argument-that nothing else could have caused the recent warming-falls apart.
Finally, let me state something about the recent “pause.” It is sometimes argued that, just because there has been a negative trend in the last ten years (and no significant trend for something like 15) does not mean that anything is really amiss: they point to two periods in the last 30 years, during a warming trend that latter continued, of about ten years in length. Those making these arguments, whether they be prominent, respected scientists at NOAA or NCAR (Easterling and Wehrner, Trenberth and Fasullo) or internet trolls (I find increasingly, in terms of intelligence, there is no difference) it highlights either the ignorance, incompetence, or dishonest of these individuals (in the latter case, who are federally funded to provide intelligent honest analysis to the American taxpayer!). Why do I have such a harsh judgement? Because: while it is technically true that there were indeed pauses during those periods, those pauses are associated with periods impacted by major volcanic eruptions, and it was those which caused the warming to halt during those periods: there is no indication that a similarly large eruption happened recently in the time frame necessary to be responsible for the halting of warming. Indeed, if we look at ten year trends by end date, and identify the period when they first become almost continuously positive (the 120 month trend ending in October of 1979 (that is, beginning in November 1969) so we may identify this as the start of the warming period) and look at trends in data before and after correction for the effects of volcanic eruptions, we find that both earlier, very brief halts in warming, disappear, and the warming trend becomes unambiguously continuous until recently, when it stops and goes negative:
The above shows 120 month trends, in K per annum, red without volcanic effects removed, blue with volcanic effects removed. You can see that in fact there was only one (very brief) period when the ten year trends dipped negative before, the later period associated with Pinatubo did not, in fact, go negative, merely very close to zero. Second, we see that picking periods beginning in about 1992 for trends is an excellent way to exaggerate warming to give the impression of a rapid rate, but this is dishonest because the cause of this elevation of the trend is due Pinatubo occurring at the beginning of such trends (eruption in 1991, results in maximum dip around about 1992). I recall some other “scientists” of the SS “skeptics are conspiracy theorists” crowd using exactly that to argue the trends are on par with models, but such dishonest scumbags are really not worth dignifying by naming them. What we see is that the halt in warming is without precedent in the recent warming period. As such, something *is* amiss with predictions of not only continued, but *accelerated* warming. The something that is amiss appears to be that:
- Sensitivity has been very significantly over estimated and
- Natural climate variability, whatever the cause, has been under estimated.
The former undermines the claim of drastic future warming, the latter undermines the claim that recent warming was uniquely attributable to anthropogenic forcing.
Let’s be absolutely clear: that represents a complete vindication of the skeptical position and a refutation of the alarmed position.