@ Agronomist,

>> Just to let you know - cohenite is Anthony Cox. <<

Pure gold!

Agronomist says this:

"The lines are meaningless with respect to the underlying mechanisms, so any predictions will only be correct by chance."

You are obviously clueless and do not understand the paper which links the statistical model to well established physical processes and events such as the Great Pacific Climate Shift and variations in ocean upwellings. Did you miss those agronomist just like you missed the fact that not all the temperature indices show a statistically significant increase since 1997. I guess that is about what you would expect from a statistical illiterate.

And this gibberish from you:

"It would be like me predicting temperature will continue to increase by 0.8 C per century on the basis of that is what it has done recently. It would be a meaningless prediction."

That is exactly what AGW theory pretends to do!

Papers about breaks in climate process are well established; see, for example:

https://pantherfile.uwm.edu/kswanson/www/publications/2008GL037022_all.pdf

Swanson and Tsonis find a break in 2002 compared with 1997-1998 in the Stockwell and Cox paper but use different combinations of physical factors.

Knox and Douglass select 2000 for the down break after the up break about 1976:

http://www.pas.rochester.edu/~douglass/papers/Douglass_Knox_pla373aug31.pdf

While statisticians Breusch and Vahid isolate a unit root in the recent temperature data and no down break in the 1990's:

http://cbe.anu.edu.au/research/papers/pdf/wp495.pdf

A unit root in a data stream means the data stream cannot be modelled with a linear analysis which is why a Chow test was used in the Stockwell and Cox paper; it also means that agronomist's remark that "Straight lines are perfectly adequate for asking questions about trends." is meaningless.

I am continually astounded by the hubris of the pro-AGW believers here and elsewhere. I guess it is a defence mechanism to the paucity of both evidence to support their belief structure and their inability to accept that paucity.

But carry on; it's a distraction.

- - - puke

cohenite, despite your protestations the lines on the graph are essentially meaningless with respect to underlying mechanisms. The explanations given for the mechanisms in Stockwell and Cox are post hoc ergo propter hoc. As soon as anyone starts a trend line with 1998, I know they are confounded by the noise in the signal. That means the paper by Stockwell and Cox remains junk.

Swanson and Tsonis were indeed looking at the noise – or climate variability as they called it. There are several factors that contribute to variability in global temperatures with time. A big percentage of the short term noise is the result of ENSO. El Nino periods tend to increase global surface temperature above the average and La Nina periods tends to decrease global surface temperature. 1998 was one of the strongest El Nino periods on record and we have just come out of one of the more intense La Nina periods on record. When you strip away the noise, as Swanson et al. have done here http://deepeco.ucsd.edu/~george/publications/09_long-term_variability.pdf for example, what you will find is the underlying trend.

Anyone with a modicum of understanding would know that you have to deal with the climate variability to get at the underlying trend. Once an understanding of that is gained, useful predictions (anyone can make useless predictions as Stockwell and Cox have amply demonstrated) can be made about the future

"As soon as anyone starts a trend line with 1998, I know they are confounded by the noise in the signal. That means the paper by Stockwell and Cox remains junk."

You miss the point; if 1998 is a break point, as the Chow test found, then you are entitled to make a prediction on the basis of other breaks and potential patterns revealed by those breaks; it's been done many times by pro-AGW papers which argue that temporary noise masks the true AGW signal such as the Keenlyside effort and the astounding Easterling paper:

http://www.nature.com/nature/journal/v453/n7191/full/nature06921.html

http://www.esrl.noaa.gov/psd/csi/images/GRL2009_ClimateWarming.pdf

"post hoc ergo propter hoc"

This is just lazy; much of the Stockwell paper provides great detail on the physical processes occuring at the time of the 1976 up-break and the 1998 down-break, and you have mentioned a dominant one, the ENSO phase switch. How is it tautalogical to say those concurrent climatic factors played a role in the temperature trend?

Which leads to Tsonis and Swanson's paper concluding that natural variability contributes very little to trend.

There are many papers which also agree with T&S including the infamous Foster et al reply to McClean et al. I am quite happy to discuss the natural variablity vs underlying AGW trend issue because it is far from settled. For instance the T&S paper relies on a modelled SST/atmosphere coupling and concludes AGW dominates trend. This paper does the same and reaches the opposite conclsion:

http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-11-00148.1?journalCode=clim

The reality seems to me that the heat has gone out of the debate and we can leave the argument to the climate scientists who as is their wont will going on arguing to the end of time.

Meanwhile the so called carbon price (aka tax) is in tatters. One could reasonably say that the tax has degenerated into “a dog’s breakfast.” With the floor price gone, the tax is now but an irritating token gesture to Green influences. No sensible Government will allow the price to rise to a level where it has an adverse effect on industrial progress and development. In Australia, with all the so called compensatory payouts, much boasted about by the Gillardits, the carbon tax will cost a bomb to administer and thus be a negative on Swanny’s budget.

It cannot be long now before an incoming Abbott Government will sweep the tax away into the dustbin of history.