CLIMATE CHANGE AND HORSEHOCKS

Louis Hisskink emails me as follows:

Recently Stephen McIntyre and Ross McKitrick had a peer reviewed paper (http://www.agu.org/pubs/crossref/2005/2004GL021750.shtml) published in Geophysical Research Letters on February 12, 2005. They add further rigorous analysis of the Mann et al temperature reconstruction that resulted in the famous IPCC Hockey Stick Graph which showed unprecedented global warming during the 20th century. This graph has now been proven to be the result of sloppy statistical analysis and is essentially the result of pathological science.

Studying the graphs on McIntyre's blog, as well as other sites, I noticed that all of the graphs invariably are published as temperature anomaly graphs (the difference between a long period average temperature and the mean for a particular year) and that the variation was in the order of a decimal point of the temperature unit, Kelvin, or more widely known as Degrees Celsius.

This representation of data is used to enhance extremely subtle signals hidden in stronger signals. In order to further emphasise this anomalism, the vertical scale is exaggerated. What does this mean practically?

Basically nothing. The variation from the long term mean, being within +/- 0.5 Deg Celsius, is to all intents and purposes within the reading error of a standard thermometer. Furthermore a temperature variation of this magnitude is physically imperceptible. Can you detect a variation of +/- 0.5 deg Celsius in your bath water using the tip of your elbow?

This raises the issue of what accuracy can we read thermometers. As meteorological stations need to record the range of possible temperatures, specifically from -60deg Celsius to + 60 Deg Celsius, we need to construct a glass thermometer at a suitable size. As we cannot physically discern a temperature change of less than 1 degree Celsius, there is no need to calibrate a mercury thermometer in decimal fractions of a degree, hence the measurement limit of such a thermometer would be X +/- 0.5 degrees Celsius, the calibration resolution, or Measurement +/- 0.5 deg Celsius. This measurement resolution is adequate for climate purposes, since diurnal variations generally fall within a range of 45 Degrees Celsius.

The daily fluctuation of the temperature in Perth, for example, varies from a minima of say 10 degrees to almost 40 degrees Celsius in summer - a 30 degree range. Superimposed on this diurnal variation is a subtle signal at the limit of detection of your measuring thermometer - variations less than 0.5 degrees Celsius. In fact variations you cannot actually measure with a standard thermometer.

Strangely, or not so strangely for climate skeptics, the debate about temperatures for the last 10,000 years is a debate over temperature anomalies within the error margin of standard mercury thermometers. This is in addition to the erroneous way in which the surface temperature measurements are collated, in 5x5 degree blocks of latitude/longitude. Vincent Gray, has done an independent analysis of the recorded surface temperatures here (http://www.john-daly.com/guests/regional.htm).

In other words much ado over nothing. This climate debate is no different from the theological debate over how many angels could be fitted onto a pinhead.

As Colonel Harry Potter of the MASH TV series would have concluded, the global warmers, or climate changers as they now have decided to call themselves, (talk about delusions of grandeur) are spruiking horsehocks.

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Many people would like to be kind to others so Leftists exploit that with their nonsense about equality. Most people want a clean, green environment so Greenies exploit that by inventing all sorts of far-fetched threats to the environment. But for both, the real motive is to promote themselves as wiser and better than everyone else, truth regardless.

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