Always has, always will.
I just finished Ian Plimer‘s book, Heaven and Earth, which provides a very extensive and compelling argument against anthropogenic global warming. Thus was a even further angered by Jeffrey Simpson’s ridiculous column in the Globe and Mail:
The world faces its greatest tragedy of the commons with the warming of the planet’s atmosphere that is overwhelmingly caused by human activities, especially emissions of carbon dioxide and methane. Crank scientists and their dwindling band of supporters contest this warming, but the overwhelming majority of scientists have declared it to be a fact. Indeed, the latest scientific evidence suggests an acceleration of warming trends.
Of course he belittles those scientists (not a dwindling band of cranks) who question the orthodoxy in the manner that the scientific method demands. And then he says something that is demonstrably not true. The latest scientific evidences shows that the world has not warmed since 1998 and that cooling is expected to continue for 20 years or more. Of course this was not predicted by the general circulation climate models used by the IPCC.
And today, I find the (hopefully) final nail in the Hockey Stick over at Climate Audit.
Back to Ian Plimer’s book, while the vast dump of information he provides that must force the reader to question the orthodoxy of global warming, to me that was not the overwhelming message. To me, the issue of climate change and whether human activity has had a significant impact can be shortened to a simple adage from the late Carl Sagan:
Extraordinary claims require extraordinary evidence
This goes to the scientific method and practice that consensus is meaningless if even one piece of evidence contradicts a theory. The consensus before 1859 was that all living things had been created in their current forms, then Charles Darwin published On the Origin of Species. The consensus before 1905 was that time and space were inviolate and that the universe was filled with an æther in which light propogated; then Albert Einstein published the seminal paper of Special Relativity.
Today, there is purported to be a consensus that human combustion of carbon based fuels that has increased the concentration of CO2 from 300 to 385 parts per million in the atmosphere has a significant impact on the climate, yet the same models that predict this cannot explain the warming and cooling that has occurred over the last 55 million years, let alone the last 160,000 years of cyclical glaciation or even the Holocene cycles (warming in Minoan, Roman and Medieval and Modern periods, with cooling in between).
It should not be the responsibility of the so-called “deniers” to provide proof that human activity is not driving the climate – it is the responsibility of the “warmists” to explain how it is they are so certain that the mechanisms that have driven the climate to vary over the millions of years the Earth has existed are not behind any change that may be occurring today.