Like a simple parlor trick, the networks are able to make skeptical scientists vanish, at least from the eyes of their viewers.

In some cases, the broadcast networks have failed to include such scientists for years, while including alarmist scientists within the past six months. ABC, CBS and NBC's lengthy omission of scientists critical of global warming alarmism propped up the myth of a scientific consensus, despite the fact that many scientists and thousands of peer-reviewed studies disagree.

Neither CBS nor ABC have included a skeptical scientists in their news shows within the past 1,300 days, but both networks included alarmists within the past 160 days -- CBS as recently as 22 days ago. When the networks did include other viewpoints, the experts were dismissed as "out of the scientific mainstream" or backed by "oil and coal companies."

The networks were able to promote the myth that there is a scientific consensus for man-made, catastrophic climate change by including climate alarmists much more often than skeptical scientists and by challenging the credentials of the skeptics that they did include.

There are thousands of skeptical scientists, so it's not like the networks couldn't find any. Marc Morano, who runs the website Climate Depot, has published a special report listing more than 1,000 dissenting scientists worldwide who dispute man-made global warming claims made by the likes of the United Nations Intergovernmental Panel on Climate Change (IPCC) and former Vice President Al Gore.

CBS was the worst, ignoring skeptical scientists for 1,391 days, ever since the May 15, 2010, "Evening News." That night, CBS interviewed former NASA climatologist, Dr. Roy Spencer during an extensive profile of alarmist meteorologist, and non-Ph.D., Dan Satterfield.

It was just 22 days ago, on Feb. 12, 2014, that CBS included an alarmist physicist, Dr. Michio Kaku on "This Morning." Kaku is a contributor to "This Morning" and that day he warned of the "heating up of the North Pole" which "could cause gigantic storms of historic proportions."

ABC last included a skeptical scientist 1,383 days ago. During the May 23, 2010, segment of "World News," ABC played a brief, 23-second clip of Princeton-educated Dr. Fred Singer expressing his skepticism over man-made climate change, along with clips of two alarmist scientists. Singer's was the only opposing view in that report and his views were actually taken from a much earlier interview aired on ABC March 23, 2008.

Dr. Michael Oppenheimer, a Princeton professor, appeared on ABC "World News" Sept. 27, 2013, arguing that climate change is "bearing down on us," only 160 days ago.

NBC did a far better job than the other broadcast networks, but the last time they included a skeptical scientist was still a whopping 298 days ago. NBC's May 13, 2013, "Today" included Dr. Jay Lehr of the Heartland Institute. Lehr criticized the supposed link between carbon dioxide and global temperatures.

An alarmist scientist appeared on NBC much more recently, however, only 115 days ago. On Nov. 11, 2013, "Today" Dr. Raghu Murtugudde predicted the increase of high-intensity hurricanes during a segment on how global warming would make hurricanes more powerful.

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