[ExI] Phil Jones acknowledging that climate science isn'tsettled

Max More max at maxmore.com
Thu Feb 18 02:00:26 UTC 2010


See this is what happens... I'm spending way too 
much time on a point that really doesn't 
matter... I just find it frustrating that it's 
difficult to come to a conclusion even about a 
relatively narrow issue like temperatures trends in the most recent years.

>You know, what struck me about all the data 
>presented in that article is that they include 
>the anomolous data from approx '98, and nothing from before it.

Yes, you're right. That is a problem. Picking 
different base years would affect the results. 
But how much? Look at the charts again -- it 
seems clear that the moderated warming/actual 
cooling picks up in the last years. So, just 
start in 1999, 2000, or 2001, and recompute the 
numbers. I think the point would be essentially 
the same, although the analysis would yield somewhat different numbers.

Although I don't have them at hand right now, I 
know I have seen other analyses which definitely 
and explicitly avoided starting at 1998. Googling around, I see this:


-- which argues that temperature trends *since 
2001* fall well below IPCC projections. I 
remember reading other reasonably credible 
sources that agree with that, and others that disputed it.

One commentator says:

John V (Comment#1009) March 10th, 2008 at 8:53 pm

Hmmm, my numbers don’t quite match yours. I hope 
you don’t mind a question or two to track down the discrepancies:

Using monthly data, I get the following global 
trends from Jan 2001 to Feb 2008:

GISS: +0.83 C/century
HadC: -0.55 C/century
RSS: +0.41 C/century
UAH: -0.07 C/century
AVERAGE: +0.16 C/century

However, when I compute the trends from Jan 2002 to Feb 2008 I get:

GISS: -0.29 C/century
HadC: -1.67 C/century
RSS: -0.91 C/century
UAH: -1.71 C/century
AVERAGE: -1.14 C/century

I cannot evaluate those numbers, since I don't 
know Cochrane-Orcutt. Anyway, as I said before 
(and I think you agreed), these short-term trends 
really don't tell us anything, so I'm going to 
try not to spend more time on this particular 
point. Actually, it's really quite annoying that 
the author did use 1998 as a base year. That just 
obscures the point that was to be made by opening 
him (rightly) to cherry-picking charges.

It is clear to me that there are plenty of 
analyses suggesting that warming has recently 
been below trend that do NOT depend on starting with 1998. For example:

The following post seems quite interesting and 
helpful. It explains why Lindzen's claim that 
there has been no "statistically significant" 
warming over the last 14 years (since 1995, not 
1998, note) is "not wrong, per se, but neither are they particularly robust":
A Cherry-Picker's Guide to Temperature Trends (down, flat–even up)

and, related:

BTW, I notice that even Gavin at RealClimate 
acknowledges that "(2) It is highly questionable 
whether this “pause” is even real. It does show 
up to some extent (no cooling, but reduced 
10-year warming trend) in the Hadley Center data"
Again the GISS data gives a different result. (At 
a quick look, I don't see him discuss the other 
two datasets.) Of course RealClimate attacks the 
analysis, then that attack is attacked...

There's more commentary on the disagreement here 
(but, note, using only Hadley and GISS):
Among "lucia's" conclusions: "It does look like 
both RC [RealClimate] and Lindzen are doing some 
cherry picking of different sorts as suggested by Chip in his article."

I don't think you can rightly dismiss doubts 
about claims of continued or accelerated recent 
warming by looking only for those who start their 
charts with 1998. I agree completely, however, 
that it's right to criticize those who do so.

Sorry for wasting your time and mine on this 
rather insignificant (but annoyingly nagging) issue.


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