no pause

Mal Adapted says:
November 21, 2017 at 11:44 pm

angech:

All the hand waving afterwards and altering of the data sets afterwards do not change the premise, at the time, on the data that was available and used, that there was a pause.

Except there was no pause, if by ‘pause’ you mean a short-term interval when the slope of the long-term statistical trend in GMST fell to zero. There was an interval between 1998 and 2012 when observed GMST appeared to the eye to rise more slowly than projections for that interval produced by an ensemble of coupled GCMs, although still within modeled lower confidence bounds. Change point analysis, more rigorous than eyeball methods, found no statistically significant change in the trend of the previous three decades. From the latter article, by Rahmstorf, Foster and Cahill earlier this year in ERL:

[T]he data are fully consistent with a steady global warming trend since the 1970s, superimposed with random, stationary, short-term variability. All recent variations in short-term trends are well within what was to be expected, based on the observed warming trend and the observed variability from the 1970s up to the year 2000. We discuss some pitfalls of statistical analysis of global temperatures which have led to incorrect claims of an unexpected or significant warming slowdown.

Although the alleged ‘pause’ was not statistically significant and was conclusively terminated in 2014, it attracted attention from climate scientists seeking to resolve ‘internal’, short-term variability to forcings. Rather than casting doubt on the AGW consensus, the short-term slowdown in observed warming led to refinement of models as well as datasets. Climate science advanced pretty much as one expects, and the consensus case for AGW grew still stronger. AGW-deniers hoping to weaken it, OTOH, found their ‘pause’ rhetoric had backfired ;^D!
angech says:
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November 22, 2017 at 2:45 am

“The problem becomes worse, in that a lot of people here dispute that there was a pause at all”
Mal Adapted says: re
“All the hand waving afterwards and altering of the data sets afterwards do not change the premise, at the time, on the data that was available and used, that there was a pause.”

“Except there was no pause, if by ‘pause’ you mean a short-term interval when the slope of the long-term statistical trend in GMST fell to zero”

Note I did say premise, not fact.
And thank you for one definition of what a pause might be.
It is difficult to discuss what one believes does not exist.
Particularly when giving proof that it did not exist because you [*Xiangdong Zhang] have found extra missing data that proves it did not exist.
angech says:
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November 22, 2017 at 3:12 am

Mal Adapted
“Except there was no pause, if by ‘pause’ you mean a short-term interval when the slope of the long-term statistical trend in GMST fell to zero”

I would be happy with a definition of a pause, in general, to be a zero slope trend for any graph with a time base over any reasonable fraction of the presented graph.
This is not a standard definition but since we are discussing unicorns this is the sort of definition I would prefer.
At Lucia’s 2 years ago she and others argued that a steady slope with no acceleration could be taken in some circles to mean a pause. I get the idea of a non changing rate being paused but in the real world I would insist on a zero slope, that is there was a rate which has now altered to a zero slope.
As for short term there is no short term in my definition if showing a single pause as the requirement is for it to be visible on the graph shown.

Commenting specifically on “[T]he data are fully consistent with a steady global warming trend since the 1970s, superimposed with random, stationary, short-term variability”
We have a graph of 47 years, the authors dispute the existence of a pause while admitting several occurred by my definition [random, stationary, short-term variability]. Karsten himself acknowledges a pause was seen and named by some people ” the inappropriately named “hiatus”. John Hart references “average global temperatures from 1998-2012 ” which would be a significant 14 years out of 47, hardly short term in the context of a 47 YO graph.

Since a lot of people here dispute that there was a pause at all.
Not to mention all authors referenced above
With good arguments.
Too short a time frame.
The graph actually went up 0.05C in the misquoted study.
Cherry picking a time after El Nino.
Definition of a pause is completely wrong.
etc.
There is no need to throw in studies showing there was a pause but….

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