If a forecast is wrong, it is not surprising for it to be quickly shown to be wrong by subsequent data. But the method needs to be held constant. Sure there are other methods, but then you get into my method vs your method, rather than showing an error of judgment, on their chosen method.

I don’t think its fair to the journal to post before publication, and editors can reject on that basis.

I see your point, though “fragile” is the right word, not bogus – you can’t show Rahmstorf is wrong, just that he hasn’t made the case.

There is certainly a contradiction between your results and Lucia’s analysis. You show that temperatures are near the mid-range of IPCC TAR,

http://landshape.org/enm/wp-content/uploads/2008/10/liite5_paivitetty_rahmstorf.jpg

while Lucia shows them falling below. I think the model comparison is different, but this might also to be due to her using long-term linear least-square trends, which will always fall below even a perfect model which predicts temperatures above a linear trend.

An OLS trend is also a poor choice as it weights data points at the beginning of the series equally to the most recent. The best estimate of the future trend at any point will be from a Kalman filter, which reduces to an exponentially weighted least squares trend. Wouldn’t this be the best way of comparing data to the model?

By the way, have you posted a version of your submitted article on this?

That is the point, that Rahmstorf, Hansen and others made their heavily cited
conclusions on the basis of an uncertain pretext. To say, ‘O but its only
a couple of years data and the endpoint is very uncertain’, and then say that
Rahmstorf et al’s analysis is correct and wonderful is completely inconsistent.

I am not claiming that the trend has turned down. I am claiming that
Rahmstorf’s conclusion that the climate models underestimate was so fragile
that even two years data shows it to be bogus.

Your analysis is heavily skewed by a single year’s inclusion, 2008. 2009 is shaping up considerably warmer, and so the trend is now being pushed up again.

Given the noise in the data, the end of trend line will always be wiggling around like the head of a snake. You’ve snapped the snake head looking down, as it has before, but the full movie will show it’s often pointing above trend. If you use monthly rather than yearly data and calculate up to date you’ll see the snake is starting to look up again.

Should a paper on this topic be so time sensitive that its conclusions depend on whether the trend is calculated in 2006, 2008 or 2009?

How about GWAVA, Global Warming, Anthropogenic, Very Alarming…
That one sounds silly too…

I have submitted a different conclusion with the same analysis method, simply with two additional years data. The non-linear trend is no longer in the upper region of the IPCC projections for temperature. See powerpoint at post http://landshape.org/enm/newcastle-lecture-update/ for the image.

I compare these observed longer (20-year) trends to the IPCC early 21st century projected trend of 0.2 C/decade, based on the multi-model ensemble used in IPCC AR4 WG1 Chapter 10 projections.

Deep is not comparing apples to apples. The models’ projected 20 year trends with endpoint 2009 would be far lower than 0.2c/decade if a couple of stratospheric volcano eruptions had occurred within the last 5 years (volcanos cause cooling) and no eruptions had ocurred for the preceding 15 years.
Now that is not the case. El chichon (’82) and Pinatubo (’91) erupted followed by a vulcanic lull until now, making the models’ projected trend higher than 0.2C/decade as Lucia has explained.

Deep refuse to understand. I trust he will maintain his point about the fixed benchmark of 0.2C/decade should a large stratospheric volcano erupt in the near future and the 20 year observational trend in 5 years time is no longer affected by the Pinatubo eruption at the other end of the 20 year trend line ;-)

http://rankexploits.com/musings/2009/hadcrut-march-data-available/

Looks like the individual comment links are not unique.

You’ll have to scroll down to read Lucia’s relevant comments.

Deep is not comparing aples to aples. The models’ projected 20 year trends with endpoint 2009 would be far lower than 0.2c/decade if a couple of stratospheric volcano eruptions had occurred within the last 5 years (volcanos cause cooling) and no eruptions had ocurred for the preceding 15 years.
Now that is not the case. El chichon (82) and Pinatubo (91) erupted followed by a vulcanic lull until now, making the models’ projected trend higher than 0.2C/decade as Lucia has explained.

Deep refuse to understand. I trust he will maintain his point about the fixed benchmark of 0.2C/decade should a large stratospheric volcano erupt in the near future and the 20 year observational trend in 5 years time is no longer affected by the Pinatubo eruption at the other end of the 20 year trend line ;-)

http://rankexploits.com/musings/2009/hadcrut-march-data-available/

compare these observed longer (20-year) trends to the IPCC early 21st century projected trend of 0.2 C/decade, based on the multi-model ensemble used in IPCC AR4 WG1 Chapter 10 projections.

Except Lucia and others have pointed out to you that you’ve sort of cherry-picked that 0.2 C/decade benchmark (how ’bout those volcanoes?)

http://rankexploits.com/musings/2009/hadcrut-march-data-available/#comment-12890

http://rankexploits.com/musings/2009/hadcrut-march-data-available/#comment-12900

I compare these observed longer (20-year) trends to the IPCC early 21st century projected trend of 0.2 C/decade, based on the multi-model ensemble used in IPCC AR4 WG1 Chapter 10 projections. This same benchmark was used by Roger Pielke Jr and Pat Michaels in their analyses, and is fairly standard as far as I know.

The 20-year trends for GISTemp, NOAA and HadCRUT were all ahead of the benchmark earlier this decade, and are presently a little under. This fluctuation about the benchmark value is hardly surprising, given normal interannual variations and a relatively cool La Nina year at the end point.

See:
http://deepclimate.org/2009/04/18/20-year-surface-trends-close-to-models/

http://deepclimate.files.wordpress.com/2009/04/20-year-trend.gif

Thanks for reading.

Please read the y-axis label of the three figures: it is the trend, not the temperature that is decreasing. All three figures indicate we continue to warm, not cool.

Can you offer any explanations for that?

Tom P, thanks for giving us an example of the reality denial that pervades the Warming Believer camp.

According to you, temperatures going down is not cooling.

Why do you think that this public demonstration of your personal antipathy towards Lord Monckton is of any interest to anyone?

Rather than continuing to speak through your backside, I suggest that you put it back in your pants, where it undoubtedly belongs, and then …. sit on it!

“The new acronym should be AGWA for Anthropogenic Global Warming Alarmism.”

Great idea, because it’s pronounceable–and sounds silly.

(BTW, since AGW isn’t pronounceable, it isn’t an acronym.)