Canadian ecologist Patrick Moore, known as one of the co-founders of the activist group Greenpeace, has a history of sharply dissenting from policies supported by major environmental groups, including the one he helped create. Moore’s latest departure is to assert that climate change, particularly the gradual warming of Earth’s surface temperature over the last century, is not caused by humans.

“There is no scientific proof that human emissions of carbon dioxide are the dominant cause of the minor warming of the Earth’s atmosphere over the past 100 years,” Moore said during an appearance before the Senate Environment and Public Works Committee on Tuesday. “If there were such a proof it would be written down for all to see. No actual proof, as it is understood in science, exists.”

The ecologist, who worked with Greenpeace from 1971 to 1986 and left “not necessarily by his own choice,” went on to found Greenspirit Strategies, an environmental and sustainability consulting firm in Vancouver.  

“After 15 years in the top committee I had to leave as Greenpeace took a sharp turn to the political left, and began to adopt policies that I could not accept from my scientific perspective,” Moore said. “Climate change was not an issue when I abandoned Greenpeace, but it certainly is now.”

Moore argued that the sophisticated computer models scientists use to predict patterns in global climate are “not a crystal ball.” He maintained that the claim by the Intergovernmental Panel on Climate Change that humans are “extremely likely” to be the dominant cause of global warming since the mid-20th century is bogus, given that the scale used to measure probability was constructed by IPCC members themselves.

“Perhaps the simplest way to expose the fallacy of ‘extreme certainty’ is to look at the historical record. …When modern life evolved over 500 million years ago, CO2 was more than 10 times higher than today, yet life flourished at this time. Then an ice age occurred 450 million years ago when CO2 was 10 times higher than today. There is some correlation, but little evidence, to support a direct causal relationship between CO2 and global temperature through the millennia,” Moore argued.

Moore said this “fundamentally contradicts” the notion that man’s CO2 emissions are causing the planet to warm.

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