A leading climate scientist who has become skeptical of the impact of mankind on climate claims he fears for his safety amid a “witch hunt” by American global warming activists.

Lennart Bengtsson, a research fellow at the University of Reading in England, said the attacks from the international “climate science community” came after he joined the academic advisory council of a group that questions the theory of man-caused global warming, the Global Warming Policy Foundation.

“I have been put under such an enormous group pressure from all over the world that [it] has become virtually unbearable. It is a situation that reminds me [of] the time of McCarthy,” he wrote in his resignation letter.

Bengtsson, a native of Sweden, puts most of the blame on U.S. climate scientists.

“It was the climate science community the U.S. which took this very negatively,” he told the London Times. “I think the reason is the very loaded atmosphere in the U.S. [which] would like to do something very substantial about climate change.”

A report from the Global Warming Policy Foundation, noting Bengtsson accepted the position only a few weeks ago, described the opposition as a “witch hunt.”

Bengtsson noted one scientist employed by the U.S. government threatened to withdraw as co-author of an upcoming paper.

The foundation, launched by several leaders in the United Kingdom in 2009, explains it is unique in its open-minded approach to the “contested science of global warming.”

It is concerned about environmental impacts but also is “deeply concerned about the costs and other implications of many of the policies currently being advocated.”

It does not, however, “have an official or shared view about the science of global warming – although we are of course aware that this issue is not yet settled.”

“Our main focus is to analyze global warming policies and their economic and other implications. Our aim is to provide the most robust and reliable economic analysis and advice,” its organizers stated.

The Climate Depot, run by Marc Morano, reported a German physicist, Rupert Darwall, likened the reaction to Bengtsson’s decision to join the foundation advisory board to the reaction of someone joining the KKK.

“In their persecution of an aged colleague who stepped out of line and their call for scientists to be subject to a faith test, 21st-century climate scientists have shown less tolerance than a 16th-century monarch. There is something rotten in the state of climate science,” said Darwall.

Another expert, Judith Curry, said such disgraceful behavior “has the potential to do as much harm to climate science as did the Climategate emails.”

The emails, hacked from the University of East Anglia Climate Research Unit several years ago, showed climate scientists admitting that there was no sudden spike in global warming and exposed their frantic efforts to cover up evidence.

Bengtsson is a former director of the Max Planck Institute for Meteorology in Hamburg, Germany, and author of more than 200 papers.

In Bengtsson’s letter of resignation, he said: “If this [pressure] is going to continue I will be unable to conduct my normal work and will even start to worry about my health and safety. I see therefore no other way out therefore than resigning from GWPF.

“I had not expected such an enormous world-wide pressure put at me from a community that I have been close to all my active life,” he said.

David Henderson, in a response from the foundation, wished Bengtsson well.

“Your resignation is not only a sad event for us in the foundation: it is also a matter of profound and much wider concern. The reactions that you speak of, and which have forced you to reconsider the decision to join us, reveal a degree of intolerance, and a rejection of the principle of open scientific inquiry, which are truly shocking. They are evidence of a situation which the Global Warming Policy Foundation was created to remedy,” he said.

One of his “heresies” recently was posted at Climate Depot.

There, he said, “we cannot yet separate well enough the greenhouse effect from other climate influences … although the radiative forcing by greenhouse gases (including methane, nitrogen oxides and fluorocarbons) has increased by 2.5 watts per square meter since the mid-19th century, observations show only a moderate warming of 0.8 degrees Celsius … high values of climate sensitivity, however, are not supported by observations.

“Thus, the warming is significantly smaller than predicted by most climate models … since there is no way to validate them (models), the forecasts are more a matter of faith than a fact.”

In the U.S., NASA’s James Hansen reportedly called for trials of climate skeptics in 2008 over “high crimes against humanity.” And environmentalist Robert F. Kennedy Jr. lashed out at skeptics in 2007, declaring, “This is treason. And we need to start treating them as traitors.”

According to Morano’s compilation of criticisms, former Clinton administration official Joe Romm defended a comment on his Climate Progress website warning skeptics would be strangled in their beds.

“An entire generation will soon be ready to strangle you and your kind while you sleep in your beds,” he said.

A 2008 report found that “climate blasphemy” is replacing traditional religious blasphemy. In addition, a July 2007 Senate report detailed how skeptical scientists have faced threats and intimidation.

Former Vice President Al Gore famously compared global warming skeptics to people who “believe the moon landing was actually staged in a movie lot in Arizona.”

WND reported just recently on a new report from the White House that critics charge blames Americans literally for “destroying the Earth.”

Meteorologist Brian Sussman, who authored “Climategate: A Veteran Meteorologist Exposes the Global Warming Scam,” said the agenda and the report are not necessarily linked to reality.

“Today the Obama administration released its gloom and doom National Climate Assessment. According to the 800-page report the carbon pollution created by Americans is literally destroying the Earth as we know it,” he said.

But consider the source, he strongly urged.

“The assessment is being fronted by Obama’s handpicked science adviser, John Holdren. Holdren is an ultra-radical; in fact as a former Stanford and Harvard professor he is a mentor to many prominent eco-radicals. Holdren, like all from the eco-left, believes there are too many people on the planet. He also believes that the United States Constitution allows for imposing a forced abortion policy upon the American people.”

Sussman cited Holdren in his book “Climategate” for writing, “Indeed, it has been concluded that compulsory population-control laws, even including laws requiring compulsory abortion, could be sustained under the existing Constitution if the population crisis became sufficiently [severe and] endanger society.”

Among Holdren’s ideas? A sterility drug in drinking water.

Sen. Jim Inhofe, R-Okla., the senior member of the Environment and Public Works Committee, said at the time the administration “assessment” is nothing more than a political ploy to try to help Democrats and Obama.

“This climate assessment seems conveniently timed for the week the Senate could be debating the need to approve the Keystone XL as well as expediting the export of liquefied natural gas,” said Inhofe, author of “The Greatest Hoax: How the Global Warming Conspiracy Threatens Your Future.”

“Now that another climate change billionaire, Tom Steyer, has entered the scene and put at least $100 million on the campaign table, the president and my colleagues are jumping at opportunities to sideline critical domestic energy opportunities for the United States and instead discuss global warming alarmism,” he said.

Al Gore

“Fear tactics and money are powerful tools in politics.”

Inhofe said that with his report, the president is “attempting to once again distract Americans from his unchecked regulatory agenda that is costing our nation millions of job opportunities and our ability to be energy independent.”

“The Politically Incorrect Guide to Global Warming and Environmentalism” tears the cover off the left’s manipulation of environmental issues for political purposes, showing incontrovertible evidence “catastrophic man-made global warming” is not actual science

“They know that the earth’s climate has only warmed .7 degree Celsius since the beginning of the Industrial Revolution, and 88 percent of that warming occurred before 1940. And they know that the earth’s atmosphere has not warmed for nearly 18 years,” Sussman said.

Among the dangers the White House said it expects will develop are “longer growing seasons and rising carbon dioxide levels increase yields of some crops,” which already have been “offset” by “heat waves, droughts, and floods.”

The report also warns of “too little precipitation” on the Great Plains.

“Climate change will add to both stress and costs.”

While the report made multiple forecasts, in the past, those haven’t always gone so well.

WND reported that in 2000, David Viner, a senior research scientist at the Climatic Research Unit of the University of East Anglia was warning that in just a few years, snow would be “a very rare and exciting event” in Britain.

“Children just aren’t going to know what snow is,” he said.

Then came the winter of 2013 and one really bad week for global warming adherents.

Cairo saw its first snow in 100 years. Oregon, like several other states, reached its coldest temperature in 40 years. Chicago saw its coldest days ever, and – as if to add finality to the trend – Antarctica reached the coldest temperature ever recorded anywhere on Earth.

The authoritative reputation of East Anglia was seriously downgraded in 2009 when leaked emails proved researchers were engaged in a major scheme to manipulate and suppress evidence against global warming, misconduct London’s Telegraph newspaper called “the worst scientific scandal of our generation.”

And recently, global warming advocates said, among many other things, that rising temperatures “are reducing ice volume and surface extent on land, lakes, and sea.”

“This loss of ice is expected to continue. The Arctic Ocean is expected to become essentially ice free in summer before mid-century.”

But the report became public within hours of a CBS News report that said: “In the aftermath of one of the coldest winters on record, 19 percent of the Great Lakes are still covered in ice. As of Sunday, much of the ice cover is on Lake Superior and Lake Huron. The northern part of Lake Michigan also has ice.”

The report explained: “Typically by mid April, only about three percent of the Great Lakes are on ice. Lake Michigan set a new record for ice coverage in March. The National Weather Service said the cold start to March caused ice levels on the lake to increase quickly, pushing ice coverage to 93.29 percent. … At its peak, the five Great Lakes were about 92 percent covered in ice in early March.”

WND reported Al Gore, known for wild rants about global warming, including one in which his foul language earned him the description “mentally unstable,” was at it again.

Only at that time he was complaining about those who put up “barriers” to his agenda that critics say includes cracking down on carbon emissions, buying and selling credits for that activity and putting the American coal industry out of business.

“The ‘barriers’ to doing something about climate change are business and political interests that profit off of fossil fuels – ‘dirty energy that causes dirty weather,'” he said, according to an online report about a recent speech he made.

“He compared fake science from polluters stating that humans are not to blame for the climate to tobacco companies that used to hire actors to play doctors who denied cigarettes were dangerous,” the report said.

“That’s immoral, unethical and despicable,” he said of both.

An audio clip of Gore’s obscenity-packed address can be heard here: (WARNING: Profane and obscene language is used).

Also weighing in was scientist Art Robinson, who spearheaded The Petition Project, which to date has gathered the signatures of 31,487 scientists who agree that 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.”

“This kind of shenanigan has been going on for decades,” he told WND.

Inhofe was interviewed by Aaron Klein of “Aaron Klein Investigative Radio.” The host asked Inhofe – in light of Al Gore and other global warming alarmists’ failed predictions – how progressives continue to “get away” with pushing their “green schemes” in the name of climate change.

“They don’t get away with it in the eyes of the American people,” Inhofe answered. “I find fewer and fewer members of the United States Senate that are sympathetic to this whole cause.”

Hear the entire interview:

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