Letters sent to the editor of a newspaper do not represent a random sample of the general population because most people do not write to newspapers, and the editorial staff of a paper determines which letters will be published, so a great deal of filtering occurs. Letters that have passed through the editorial filtering process represent the opinions of a vocal group of readers who, with few exceptions, do not appear to be experts on the topics that concern them. But the number of such letters that are published, suggests that that a substantial proportion of the population may share these misconceptions about scientific subjects. For this reason the way members of the public in general acquire their information is worth considering because it illustrates something about how opinions are generated in our society. Perhaps we should start by considering how a well-known myth began and was transmitted.
Between 1950 and the 1970s the myth of the Bermuda Triangle flourished in the media and in popular opinion. Many people believed that a large number of boats and airplanes had disappeared due to unknown reasons in a triangular area in the central Atlantic ocean south of Bermuda. A reference librarian at a university in Arizona wondered about the rumors, so he traced the story back to its original source, which turned out to be a fictional account in a men's magazine about a squadron of navy planes disappearing in the Atlantic Ocean. Someone who read the story must have mentioned it to someone else, who apparently did not realize that it was fiction. The next time the "story" appeared in print, it was reported as fact, not fiction. After that, it took on a life of its own; everyone who wrote about it seemed to reference only the last article on the subject, implying that the events had actually happened, so for about 20 years, many people believed that this zone had some mysterious properties.
I do not see references to the subject any longer, perhaps because other topics have captured the public's attention. Unsubstantiated claims develop a life of their own more quickly today because of the ease with which people can post things on web sites and blogs. Someone posts material about climate change (or crop circles, or aliens crashing UFOs near Roswell, NM, etc.) on the Internet, and someone else reads the file and forwards it to friends. The result is rumors developing like the mythical soldiers sprouting from dragons' teeth. The important characteristic of all of these claims is that, like the Bermuda Triangle myth, they have no supporting evidence.
Not all of the stories that persist in the media are about exotic topics such as aliens. Many of them pertain to real scientific subjects such as the ozone layer and global warming. The sources of the misinformation on these topics are not always obvious, as shown by the global warming controversy. Letters claiming that legislation to reduce carbon emissions is not necessary because warming is not occurring, and that the legislation will destroy the economy never seem to mention that these beliefs are based primarily on misinformation provided by the energy industry. Reducing the amount of carbon emitted by power plants and automobiles will have a significant adverse effect on energy companies' profits, and clearly, that is not in their best interests. So they fund "research scientists" who do no research at conservative think tanks; they fund advertising campaigns to influence the public; they hire lobbyists to interact with the legislators who will vote on laws reducing carbon emissions; and they fund conferences, supposedly on the scientific aspects of global warming, but which are attended mainly by economists.
There probably is not any organized conspiracy by companies associated with the energy industry to propagate misinformation about global warming, but their efforts do not have to be coordinated to be successful. Independent continuous public relations activities contending that regulations that constrain industry in any way are not necessary and are counterproductive are just as effective as some sort of global conspiracy. Eventually, large segments of the public become suspicious of anything that seems to involve increasing governmental actions. The amount of money spent by a number of companies independently of each other clearly has been successful in affecting the public's opinion about global warming, because surveys find that a substantial percentage of the population believes climate change is not occurring, regardless of what the overwhelming majority of professional climate scientists claim.
Lest I be accused of scapegoating by blaming just the energy industry, I will merely say that the relationship between its public relations efforts and the misinformation found in all the media (not just newspapers) on global warming passes the "duck test." Sadly, the letters published in newspapers are evidence that these public relations activities are as effective as those once used by the tobacco industry.