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Friday, April 12, 2013

What got me snipped from - 11

Werner Brozek wrote a new article at about his research on noise in the global temperature record. The reply below to the article, which I submitted to the thread as a comment has not been published there. This is the second one of the couple of comments censored at Anthony Watts' blog, which I announced before to document here. Since I apparently have been blacklisted at Watt's blog by default, currently, I am not going to put any more efforts into trying to comment over there, unless I am not treated differently any more compared to how the ones are treated who agree with Anthony Watts and his friends.

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Werner Brozek wrote:

For example, do we mean that the slope of the temperature-time graph must be 0 or do we mean that there has to be a lack of “significant” warming over a given period? With regards to what a suitable time period is, NOAA says the following:

    ”The simulations rule out (at the 95% level) zero trends for intervals of 15 yr or more, suggesting that an observed absence of warming of this duration is needed to create a discrepancy with the expected present-day warming rate.”

To verify this for yourself, see page 23 here.

And once again the quote from the NOAA report is misrepresented by you. The quote still refers to the ENSO-adjusted temperature record as it has done in the past. However, you omit this information and use it here as if the quote had established some criterion for the unadjusted temperature record. You do so, although you have been pointed out already in the past that the quote applies to ENSO-adjusted data.

Your article does not hold what the headline promises. There is no analysis in there whatsoever that allows any conclusion with respect to whether climate models are "realistic". In order to do such an analysis one would have to do an actual comparison between model capabilities to simulate specific features of the climate system and real world data. Which you haven't done.

You only show some "flat lines" in the temperature record going back different numbers of years, depending on which specific record is chosen, which by itself does not allow any conclusion with respect to the presence or absence of a trend or regarding climate models, since one always will find periods with "flat lines" in any arbitrary time series that is composed of trend and fluctuations, if one chooses the time interval only short enough. One finds similar behaviour in individual simulations with climate models. You confine your examination on those time intervals, where the noise is still masking the long-term trend. This looks to me like a pointless undertaking, unless you want to study the features of the noise.

Models aside, your exercise doesn't even provide evidence for claims like "global warming stopped", or similar. Not being able to detect a trend, because the data set is too small does not allow the conclusion that the trend was not there. None of the seemingly "flat" temperature records, which you show here, can be statistically significantly distinguished from the multi-decadal surface or lower tropospheric warming trend, which itself is statistically significant with 3 sigma or more.

You state:

For this analysis, data was retrieved from This analysis indicates for how long there has not been significant warming according to their criteria. ... (To the best of my knowledge, SkS uses the same criteria that Phil Jones uses to determine significance.)

This looks to me like another misrepresentation of what others said. Or show me where Phil Jones or anyone at Skeptical Science supposedly claimed that "warming" was significant at 95% or 2 sigma, or there was no significant warming at all. Please provide a source where anyone said something like that, allegedly.

If warming is significant with, for instant higher than 90% probability, but lower than 95% probability, it is still statistically significant. Only the probability to have wrongly rejected the Null-hypothesis (which would be no significance warming in this case) is higher. To claim that there was no "significant warming" in such a case is just wishful thinking.

As for your conclusion:

After looking at the above facts, do you feel that we should spend billions to prevent catastrophic warming? Or do you feel we should take a “wait and see” attitude for a few years to be sure that future warming will be as catastrophic as some claim it will be?

You could have started with that in your posting. Then it would have been clear from the beginning, that your starting point is political and ideological preconception that you apply as a filter for your perception and examinations. That plausibly explains the motivation for your efforts here and for your misrepresentations.

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