|San José State University|
& Tornado Alley
On the Internet in various global warming alarmist sites the question Has Global Warming Stopped? is posed and then answered with statements of the following sort.
No! Global temperatures for the last N years have been the highest since 1880.
No! Global temperatures have not declined one bit.
No! Global temperatures for the last N years are X% higher than the average gobal temperature for the 20th century.
Such statements reflect a determined resistance to any sensible meaning to the word stopped. These sort of statements are being given when the recent average global temperature values look like this.
This refusal to adhere to logic and accept empirical data is reminiscent of the days in Europe when theology thwarted the development of science. Modern science can be considered to have started with Galileo Galilei and his clear thinking and reliance upon empirical data.
Imagine then this scene at the Leaning Tower of Pisa. Galileo Galilei has dropped two weights off the tower. One is ten times heavier than the other. He is being assisted by Giuseppe who is on the ground at the base of the Tower.
Galileo: Giuseppe, have the weights stopped falling?
Giuseppe: No, Galileo. They are at the lowest points they have ever been at and their positions for each of the last 30 seconds are the lowest they have been in the last hour.
Galileo: Well, call to me when they stop falling.
Of course, what Galileo should have said was:
Of course, they are at their lowest point and staying there, you nitwit. That is what it means to be stopped.
As ridiculous as this scene would have been, this is exactly what not only global warming alarmists are saying and also government agencies which are supposed to be providing information instead of misinformation. Here is a sample of this type of statements concerning the flatness of the global temperature data for the past 13 years.
Stopped does not mean Reversed.
Variables with a stochastic component but no trend will from time-to-time achieve new record levels. The expected maximum of a statistical sample increases with sample size.
But enough of the nitwit assertions of the global warming alarmists. Here are the facts.
When the entire 180 year of data is considered it is found that there are cycles of 30 year upswings and 30 year downswings superimposed upon a long term trend of 0.5°C per century. The case for catastrophic global warming is based upon cherry-picking the period since 1975.
The source of the cycle is the Pacific (Multi)Decadal Oscillation, a natural cycle which sort of the big brother of the El Niño phenomenon. Like the El Niño Southern Oscillation there is not fixed period but one that has variations.
The current period of flatness of the average global temperature curve is merely a matter of the being near the top of a cycle and for a while the downswing of the cycle is offsetting the 0.5°C per century long term trend. Nevertheless the assertions by alarmists that the Earth is experiencing catastrophic global warming will probably continue even after the temperature graph looks like this.
Or maybe, like Stephen Schneider, former Professor of Environmental Biology and Global Change at Stanford University, they will switch from one alarm extreme to the other.
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