Lovejoy says 99.9% certainty of AGW could be only 5% by 2019 if 'pause' continues

Our favorite statistician*, Shaun Lovejoy, proprietor of laughable 99.9% confidence that all global warming recovery since the Little Ice Age is from man-made CO2, has left comments at Dr. Judith Curry's blog claiming that if the 18-26 year "pause" in global warming lasts another 5 years to 2019, the global warming scam can officially be declared dead, buried, six feet under with 95% certainty:

*being facetious: my favorite statistician is Dr. William Briggs, PhD statistics, who debunks Lovejoy here

• Shaun Lovejoy | September 1, 2014 at 6:04 pm |

  As I indicated in a comment below, the pause will have to last until 2019 or 2020 before it’s probability gets down to the 5% level which would be needed to reject the anthropogenic hypothesis at the 95% level.
• Shaun Lovejoy | September 1, 2014 at 4:41 pm | Reply
  Actually things are really pretty simple. The return periods can be estimated from the multproxies, and the mulitproxies are quite reliable up to 125 years or so (the time scale of the corresponding warming period since about 1880). Indeed, using the same methodology as described in my comment below (about the accuracy of the instrumental series), the three I used agreed to about ±-0.07 oC at 125 year time scales (the issues about medieval warming are indeed where there is disagreement- but below about 125 year scales all the multiproxies agree about the amplitudes of change to about the level indicated. Indeed one of the three multiproxies that I used was based on boreholes so that it has no paleo calibration issues, yet for 125 year statistics, it is very close to the others).

  You can then estimate the return periods of natural fluctuations from graph:

  

  (other stuff can be seen at:http://www.physics.mcgill.ca/~gang/Lovejoy.htm or:

  http://www.physics.mcgill.ca/~gang/eprints/eprintLovejoy/neweprint/Anthropause.GRL.final.13.6.14bbis.pdf)

  A cursory glance at the figure:

  

  shows that it was only in 2012 that the globe recovered from the enormous pre-pause warming (1992-1998, return period 20 – 30 years) and the temperature finally went below the long term trend line at the far right of the figure.

  Indeed, if there hadn’t been a pause, the temperature increase would have been so large as to invalidate the anthropogeneic warming hypothesis!
  According to a new stochastic analysis (under review), assuming that emissions and other anthropogenic forcings continue to grow at their current rates, the pause will have to continue until 2019-2020 before it can be used to reject the anthropogenic warming hypothesis with 95% certainty. Until now, the pause is exactly as expected and will not be very unusual for another couple of years- assuming that it hasn’t already ended….

see also 

New paper claims 99.999% certainty global warming over past 25 years is man-made

Repost on Lovejoy's 1st paper:

New paper claims the 'pause' is 'not so unusual' & 'no more than natural variability'

He's baack!...

Shaun Lovejoy has published a new paper which cites his prior claim of 99.9% confidence that one of the two temperature graphs below is your fault, and the other due to natural variability. 

Both graphs are half-century plots of HADCRUT4 global temperatures. Both use exactly the same time and temperature scales.  Can you tell with 99.9% confidence which one is 1895-1945 (Nature’s fault), and which is 1963-2013 (Your fault)?

 TIME –>

http://www.metoffice.gov.uk/hadobs/hadcrut4/data/current/download.html#regional_series

[graphs from Not A Lot Of People Know That, not Lovejoy's paper]

FYI according to Lovejoy's dodgy statistics the top graph is man-made, the bottom graph is due to natural variability.

In Lovejoy's new paper, he acknowledges a 'pause' in global warming since 1998, says it's "not so unusual" and concludes "the pause is no more than natural variability." Indeed, the pause is due to natural variability that has not been accounted for by climate models, and thus invalidates attribution claims that the past 50 years of temperature variations are necessarily due to man-made CO2. Furthermore, prior work by NOAA and others has found 'pauses' of 15 or more years are indeed unusual and would suggest the climate models are overly sensitive to CO2. According to RSS satellite data, the 'pause' has lasted almost 18 years. 

Return periods of global climate fluctuations and the pause

S. Lovejoy

An approach complementary to General Circulation Models (GCM's), using the anthropogenic CO2 radiative forcing as a linear surrogate for all anthropogenic forcings [Lovejoy, 2014], was recently developed for quantifying human impacts. Using pre-industrial multiproxy series and scaling arguments, the probabilities of natural fluctuations at time lags up to 125 years were determined. The hypothesis that the industrial epoch warming was a giant natural fluctuation was rejected with 99.9% confidence. In this paper, this method is extended to the determination of event return times. Over the period 1880-2013, the largest 32 year event is expected to be 0.47 K, effectively explaining the postwar cooling (amplitude 0.42 - 0.47 K). Similarly, the “pause” since 1998 (0.28 - 0.37 K) has a return period of 20-50 years (not so unusual). It is nearly cancelled by the pre-pause warming event (1992-1998, return period 30-40 years); the pause is no more than natural variability.