Sunday, 6 July 2014

Intent to Deceive

Manipulating data can be done in such a way, that although technically correct, it can then be displayed to appear to say something that is quite false. Here I will look at a blatant attempt to deceive by such a practice.

C3 headlines set out to show that there was no significant global warming but merely shows there is an insignificant decline in the rate of warming.

First of all the information before it has been manipulated.
This concerns the global surface air temperature and CO2 levels over the last 35 years.

Figure 1 Met Office data.
The latter part of this graph (red box) shows the global temperatures changes over the last 35 years of about a 0.5 C rise. Can this be manipulated to imply a temperature drop of about 0.04C per century over this same period?  Here is one such attempt by a site that in fact does this…

…. and then incredibly goes on to say:-

“The political agenda of "global warming" is so important to government-sponsored scientists that massive fabrication of temperature warming is required to convince policymakers and the media”.

Figure 2 copied below from this site above uses similar data to figure 1, but presents it in such a way to make this implication described above.

Figure 2. Satellite data manipulated.

Both the vertical axes have been presented in such a way as to hide any useful information and encourage the reader to make false inferences. Look no changes in the temperature and massive changes in CO2 (“statistically significant, ZERO”) and trend/century = -0.04C.

6 Month temperature anomaly change.
This of course is a measure of the rate of change of temperature. We can see from figure 1 that the rate of change of temperature is greater in the first half of this period of time but there is a lot of natural variation superimposed on this. The rate of temperature therefore has marginally declined but statistically by an insignificant amount.

If the temperature had risen linearly without variations how would a 6 month anomaly graph appear?

Figure 3 above shows how a 6 month anomaly graph would appear if there was no natural variability and the fraudulent implication would be easily recognized. However the natural variation possibly and hopefully distracts the reader from observing this fraud.  Why 6 months. A 6 month anomaly maintains the natural variability while keeping the familiar scale and still keeps a small enough offset value to give maximum deception.

The cumulative Atmospheric CO2 level.
It is common among climate “skeptics” to play down the amount of CO2 that has accumulated over this time. However in figure 2 the technique is to play up the CO2 level; to make it appear as large as possible to compare with the deceptive downplay of temperature changes.

The technique is to get CO2 increases to go from the bottom left of your screen to the top right of your screen. This is easily achieved now by assuming a starting value of zero and adjusting the independent CO2 scale accordingly.

Comparing a rate of change to absolute values.
There is nothing wrong with using this technique to show that two variables are related when this makes it clearer. For example one might speculate that the rate of loss of ice during a de-glaciation part of a cycle is related to the insolation received in the northern hemisphere during the well known Milankovitch cycles. However to use a rate of change or any other manipulation of data to obscure a relation or to attempt to show that variables are not connected is not in any way useful unless it is your intent to deceive.

This article set out to show that there was no significant warming but merely showed an insignificant decline in the rate of warming.

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