The first thing people equate climate science with is mass murderers and tyrants -- at least, that's what the Heartland Institute is trying to sell.

The conservative think tank, which is known for promoting climate change skepticism, launched a billboard campaign in Chicago this week that compares all those who accept climate science, as well as the reporters and politicians who supposedly promote it,  to notorious figures such as the Unabomber Ted Kaczynski, Charles Manson and Cuban dictator Fidel Castro. The first billboard -- featuring a photo of Kaczynski with the words I still believe in global warming. Do you? -- appeared along Chicago's Eisenhower Expressway on Thursday, according to a press release from the Heartland Institute itself.

These rogues and villains were chosen because they made public statements about how man-made global warming is a crisis and how mankind must take immediate and drastic actions to stop it, reads the press release.

Other rogues and villains that may appear on future billboards include Osama Bin Laden and James J. Lee, who took hostages inside of the Discovery Channel headquarters in 2010. A manifesto penned by Lee discussed the need for both environmental reform and population control.

In the release, the insittute emphasizes that believing in global warming is not mainstream or supported by scientists; instead, the Heartland Institute claims it is touted by crazy people to justify their immoral and frightening behavior.

However, the right-wing think tank did throw climate change advocates a (very small) bone.

Of course, not all global warming alarmists are murders or tyrants, reads the press release.

Still the very next paragraph warns that the most prominent advocates of global warming aren't scientists. They are murderers, tyrants and madmen.

The billboards appear to be a promotional tool for the Heartland Institute's upcoming International Conference on Climate Change, which be held between May 21-23 in Chicago. Confirmed speakers for this years conference include Rep. James Sensenbrenner, Republican of Wisconsin; Czech President Vasclav Klaus and Dr. Harrison Schmitt from the Apollo 17 mission.

The Heartland Institute disputes the view held by an overwhelming majority of scientists that the planet is gradually warming and that human activities -- such as the burning of fossil fuels -- are contributing to the problem.