Monday, 18 January 2010

Assassinationscience Climate Gate

As well as Leon's analysis in the Powerpoint attachment available on the Climate Sceptics Website,, Dr. John P. Costella B.E.(Elec.)(Hons.) B.Sc.(Hons.) Ph.D.(Physics) Grad.Dip.Ed. has done a very good analysis. It can be found at: (link in title)

As John says: "This is one of the darkest periods in the history of science. Those who love science, and all it stands for, will be pained by what they read below. However, the crisis is here, and cannot be avoided."

As a teaser (but it is worth your time to read his whole post), I will put here John's comment on temperature proxies:

Photo - Keith Briffa

To measure the temperature of the planet, we obviously need some thermometers. Now, it would be nice if someone was able to invent a time machine, so that we could go back over the past few thousand (or hundred thousand) years, and place accurate scientific thermometers all over the planet, to make these measurements for us. Of course, this isn’t possible, so scientists need to use other things as substitutes—or “proxies”—for these thermometers.

A key “temperature proxy” used by climate scientists is tree-ring data, namely, measurements of the patterns of the rings of trees that were growing hundreds or even thousands of years ago.

Now, even my sons (in elementary school at the time of writing) can tell me a handful of different factors that might influence the growth of a tree in a particular year: the amount of sun shining on it; the amount of rain it gets; how hot the weather is when it is growing; the conditions of the soil it is growing in; and the amount of carbon dioxide available for it to breathe in. We should imagine that the growth of a tree should, at the very least, depend on these five things.

So is a tree really a good thermometer?

As a physicist, such a proposition seems fraught with danger from the outset. Let’s pretend, for the moment, that the growth of a tree depends only on these five factors, and no others. An elementary fact of mathematics, that I used to teach to my 15-year-old high school students, is that if you have five unknowns (these five factors at any given instant of time in a particular tree’s lifetime), then you need at least five pieces of independent information to disentangle them all—and you need to know these five quantities to a high accuracy.

So to make any use at all of tree ring data, climate scientists would need at least four other completely independent “proxies”. Is this what they do?

They do not.