Presentation by Dr Phillip Machanick on 9 December 2009.

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This is the famous "hockey stick" curve. Note how big the uncertainties in measurement become as you go back in time.
The yellow circled area on the right refers to the period where actual data rather than reconstructed data was used. Note how there is no deception: the graph is clearly labelled. There is no other paper that the original email could have referred to as "Mike's Nature trick".


YouTube movie parodying this :

TASSC was a front organization created by the tobacco industry to propagate "sound science" as anything that was pro-tobacco and "junk science" as anything that was bad for them. They included a number of non-tobacco campaigns so it would not me so obvious that they were a front for tobacco. There are a few names common to the campaigns, like Fred Singer. Various right wing think tanks have fostered this campaign (TASSC no longer exists). I first discovered this material in George Monbiot's book Heat and provide more detail on my blog at


I took the original data and added 0.003 times years since start of the series to each year. This is a very crude approximation to the effect of about double the rate of warming we are currently experiencing.

If we do a proper test of statistical significance of a trend based on so little data, it will prove to be not statistically significant. But the same is true of claims about the last 10 years, or the "trend" since 1998.

I calculated this as the % difference between the high and low point of the graph. If the graph were plotted on a vertical axis starting at zero, the variation would look very small.

1913's sunspot count was a little lower. If you look at the temperature then, however, it was about 0.7C cooler than today. See a graph here and look for the J-D annual means at

If you extend the graph out to today, the temperature increase has flattened a bit but the solar irradiance curve has stayed very low. The critical thing to see in this graph is that the reasonably close relationship you can see up to about the middle of the 20th century clearly no longer applies.

A good source on this is Wallace S. Broecker and Robert Kunzig. Fixing Climate: What Past Climate Changes Reveal About the Current Threat--and How to Counter It, Hill and Wang, 2009. The book ends with some ideas for carbon sequestration that look a little optimistic but it has really good explanations of where modern understanding of climate started from.

A forcing is the initial trigger; a feedback is any secondary effect.

We want to predict where a space probe will be at time tC knowing where it was at times tA and tB. G = gravitational constant M1 = mass of a space probe M2 is another mass that will have an influence on its course The problem: the solar system has 8 planets +/- 1 and over a million asteroids. To calculate their influence exactly is not possible to do for every time instant, so we must approximate. We calculate the probe is at position C but it actually is at position D at time tC. So even with an exact formula, we get inexact results. This is how science works in the real world.

For more information go to my blog:

Pink = models that include both anthropogenic and natural influences. Blue = effect of only natural influences. Only combining natural and anthropogenic influences matches measured temperatures.

The very low figure for sea level rise at Port Kembla was highlighted in The Australian, without mentioning caveats in the report, such as that less than 20 years of data must be interpreted with caution because sea level rise varies a lot naturally between years.

The much higher values of Darwin and Broome were conveniently ignored. A lot of the denialist spin is based on cherry-picking data, rather than on looking at the big picture. Any real-world data has a lot of short-term and local variations. If we are looking at a change in the worldwide average, we cannot look at local data over a short time period.

The best science we have has the Himalayan glaciers disappearing in as little as 20 years. That means the water supply of half a billion people is under threat.

This is the temperature data I used earlier. I added the trend line. At time of writing the web site is down as part of the investigation in the theft of emails from University of East Anglia.