Did over 30,000 scientists declare global climate change a hoax? No, that's not true: The "scientists" referenced in a story making the claim were people who signed an online petition that said there was "no convincing scientific evidence" of global warming caused by human release of gases. The petition did not call it a "hoax." The signers' qualifications as "scientists" were not verified. Also, there are two decades of additional scientific evidence of climate change available since the petition was started in 1998.
The latest version of this story (which is a copy-and-paste version of a News Punch story proven false) is an article (archived here), published on September 2, 2016 with the title "Over 30,000 Scientists Declare Climate Change A Hoax." It opened:
A staggering 30,000+ scientists have come forward confirming that man-made climate change is a hoax perpetuated by the elite in order to make money.
One of the experts is Weather Channel founder, John Coleman, who warns that huge fortunes are being made by man-made climate change proponents such as Al Gore.
Despite being nearly three years old, these stories are still being widely shared. This is what social media users saw:
The story's premise that "a staggering 30,000+ scientists have come forward" is misleading since there is no validation that these are actually scientists. It includes anyone with a B.S. degree or higher in any field. As of April 2019, the petition website claims:
31,487 American scientists have signed this petition,
including 9,029 with PhDs
Past reporting indicates that the majority of the signatures were signed in the first several years. Signing the petition is not the same as "confirming that man-made climate change is a hoax perpetuated by the elite in order to make money." The petition does not "confirm" anything and not does not refer to climate change being a hoax or a money-making scheme of "the elite."
What the petition says:
We urge the United States government to reject the global warming agreement that was written in Kyoto, Japan in December, 1997, and any other similar proposals. The proposed limits on greenhouse gases would harm the environment, hinder the advance of science and technology, and damage the health and welfare of mankind.
There is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gases is causing or will, in the foreseeable future, cause catastrophic heating of the Earth's atmosphere and disruption of the Earth's climate. Moreover, there is substantial scientific evidence that increases in atmospheric carbon dioxide produce many beneficial effects upon the natural plant and animal environments of the Earth.
The "Global Warming Petition Project" can be viewed here.
The story is accurate in reporting that Weather Channel founder John Coleman considered climate change to be a hoax. Coleman, a longtime meteorologist, died in 2018 at the age of 83.