Is the hockey stick graph correct?
Who hasn’t seen Al Gore’s 2006 documentary, An Inconvenient Truth? It presents a cut and dried scientific case that carbon dioxide from burning fossil fuels is causing global warming and humanity needs to cut back back urgently.
Everyone presumes that the two graphs presented in the movie, one of carbon dioxide levels rising smoothly and the other of global temperatures shooting up like the blade of a hockey stick, are backed by unassailable evidence. They must be proven like Newton’s law of gravity.
If the science was indeed proven then it would be reasonable for journalists, politicians, teachers and hundreds of millions of students to have become anxious and motivated to do all they can to prevent a climate catastrophe.
The hockey stick graph was published in 1998 in the respected journal, Nature. The graph was the science used by Al Gore to galvanize opinion and assemble an ever-growing army of acolytes.
The hockey stick graph is symbolic
The scientific details that describe the different aspects of the Earth’s climate are complicated and nothing so complicated should be summarized in a single graph, however the hockey stick graph underpins one of the foundational presumptions of Alarmism.
The presumption is that the climate over the last few decades is has been changing abnormally. Everywhere you look in history, archeology, geology and many other academic disciplines there is plenty of evidence that there have been massive and abrupt changes in climate since the dawn of time, but if the hockey stick graph is correct these changes can be, at least to some extent, discounted.
The hockey stick graph is also symbolic for both sides in the debate about global warming. There have been many thousands of scientific papers, speeches, blog posts and videos made arguing for and against it.
For everyone on the anti-Alarmist side of the debate, the hockey stick graph is a clear case of climate scientists manipulating data to prove that the global warming theory is correct.
If the hockey stick graph is inaccurate and global temperatures have been manipulated then the graphs used in the movie can no longer be used as a straightforward justification for environmental, social, energy and tax policies.
Graphs are misleading
The graphs used to illustrate that the climate is changing are slightly misleading for non-experts because of the way they are plotted. If the y-axis showed actual average temperatures the line wouldn’t shoot up at the end – it would be virtually flat (as shown on the left). Instead the axis shows the annual temperature anomaly, which is the departure from a baseline temperature deliberately picked to make the point that recent and forecasted temperatures are abnormal, which they are not.
The science becomes a psychological thriller
What is not widely known is that the hockey stick graph was plotted from data that was selected to prove a point. The data was fudged.
The graph had far-reaching implications and the Alarmist community stepped in, and instead of challenging it they rallied around and censured anyone that argued against it.
A crime of this nature would have been covered in a 30 minute episode of CSI, with the last scene showing the offending scientists, head bowed, in front of the two heroic Canadians who exposed the skullduggery, admitting their guilt. Instead it has turned into a multi season thriller that has more to do with ideology and mass psychology than anything to do with science.