Now that there’s been time to digest the information which was leaked from the CRU, attention does now seem to be focused not just on the emails – which are damning in themselves, but also to the code used to generate the temperature data for the climate models, and the comments in the HARRY_READ_ME.txt file. Along the way, I’ll try my best to explain any acronyms or shorthand we encounter, in laymans terms and plain speaking (I’m a plain English guy meself).

So,  to the README.

And, oh boy! What a story THAT tells in itself!

You may be pondering the meaning of this blog entry’s title. Read on and all will become clear.

First of all, “GI”. Garbage In, as in, let’s look at what happens to the CRU data…

FOIA\documents\osborn-tree6\mann\oldprog\maps12.pro
FOIA\documents\osborn-tree6\mann\oldprog\maps15.pro
FOIA\documents\osborn-tree6\mann\oldprog\maps24.pro
; Plots 24 yearly maps of calibrated (PCR-infilled or not) MXD reconstructions
; of growing season temperatures. Uses "corrected" MXD - but shouldn't usually
; plot past 1960 because these will be artificially adjusted to look closer to
; the real temperatures.

“Artificially adjusted to look closer to the real temperature” – hrm.

MXD means “Maximum Latewood Density” – it’s from Dendroclimatology, whch purports to be the science of finding out climate history by looking at tree ring thickness – the theory goes that wider  rings mean that the tree being studied grew in conditions which favoured growth – narrower rings mean that the tree struggled with unfavourable conditions.

In other words, “wide rings = warm climate , narrow rings = colder climate”; you turn the tree into a Treemometer – so the theory goes.

There are problems.

Basically there’s a big problem, in fact, and it’s called the Divergence Problem – and that’s so called due to an Inconvenient Thermometer Record, the result of which is that from around the 1950’s onwards, treemometer “readings” differ from the thermometer readings! So with this in mind, go back and look at the comment again.

Related snippets…

• FOIA\documents\harris-tree\recon_esper.pro
  ; Computes regressions on full, high and low pass Esper et al. (2002) series,
; anomalies against full NH temperatures and other series.
; CALIBRATES IT AGAINST THE LAND-ONLY TEMPERATURES NORTH OF 20 N
;
; Specify period over which to compute the regressions (stop in 1960 to avoid
; the decline
• FOIA\documents\harris-tree\calibrate_nhrecon.pro
  ;
; Specify period over which to compute the regressions (stop in 1960 to avoid
; the decline that affects tree-ring density records)
;
• FOIA\documents\harris-tree\recon1.pro
  FOIA\documents\harris-tree\recon2.proFOIA\documents\harris-tree\recon_jones.pro
  ;
; Specify period over which to compute the regressions (stop in 1940 to avoid
; the decline
;

Now, the word decline… intriguing, isn’t it. Others in the blogosphere are wondering if “decline” means “decline in world temperatures”, and I’m thinking the same thing.

FOIA\documents\osborn-tree6\mann\mxdgrid2ascii.pro
printf,1,’Osborn et al. (2004) gridded reconstruction of warm-season’
printf,1,’(April-September) temperature anomalies (from the 1961-1990 mean).’
printf,1,’Reconstruction is based on tree-ring density records.’
printf,1
printf,1,’NOTE: recent decline in tree-ring density has been ARTIFICIALLY’
printf,1,’REMOVED to facilitate calibration. THEREFORE, post-1960 values’
printf,1,’will be much closer to observed temperatures then they should be,’
printf,1,’which will incorrectly imply the reconstruction is more skilful’
printf,1,’than it actually is. See Osborn et al. (2004).’

But no, actually, decline means decline in tree ring density! Remember what I explained earlier – the wider the tree ring, the more favourable the growth conditions for the tree was, (i.e. “warmer”) – so it looks like from the comments that CRU had to “reprocess” the tree-ring density data because the treemometers were saying “it was cold so we didn’t grow as much”. Now why would they do such a thing, I wonder… it couldn’t possibly be to tell fibs about the global climate, could it?

It gets worse…

FOIA\documents\osborn-tree6\briffa_sep98_d.pro
;mknormal,yyy,timey,refperiod=[1881,1940]
;
; Apply a VERY ARTIFICAL correction for decline!!
;
yrloc=[1400,findgen(19)*5.+1904]
valadj=[0.,0.,0.,0.,0.,-0.1,-0.25,-0.3,0.,-0.1,0.3,0.8,1.2,1.7,2.5,2.6,2.6,$
2.6,2.6,2.6]*0.75 ; fudge factor

What’s basically happening here, is that they are “fudging” the figures even more to look like global warming is worse than it actually is.

I could go on. There are many more examples of this, and I’m sure there will be much more revelations about the code and how the comments relate to it, in the days, weeks and months – nay years? – to come.

While I was authoring this article, I spotted a related one over at Steve McIntyre’s Climate Audit site, entitled New!! Data from the Decline, which demonstrates exactly what hiding the decline is all about. You should read that with this article in mind.

Here’s his graph, showing the “decline data” which the climate scientists were trying to hide…

The MXD data as graphed by Steve McIntyre of Climate Audit

And so we come to the end of my acronym, GIAGWO:

Garbage In Anthropogenic Global Warming Out.

GIAGWO! I’ll leave it up to you to decide how that’s pronounced