For the past 20 years, climate deniers have been claiming that science can't prove anything, that climate science is murky and that the science is just not settled.
Do these arguments sound familiar? They ought to. These were the same arguments the tobacco companies used so successfully for many years to cast doubt on whether smoking caused lung cancer.
In fact, some of the same "scientists" who worked for the R.J. Reynolds Tobacco Co. are part of the climate change denier cabal.
But actually, the deniers are right. Science can't prove anything. The best science can do is give us the likelihood that something is true. And based on the scientific evidence, 97 percent of the world's climate scientists agree that the planet is heating up and our reliance on polluting fossil fuels is the cause. On such a complicated system as our climate, it's hard to do better than that.
For those who think the 3 percent are right, let's put the question differently. Suppose you were sick and you visited 100 doctors and 97 told you that you had cancer and needed treatment immediately but 3 said you were perfectly healthy. Who would you listen to?
During the tobacco debate, tobacco "scientists" argued we couldn't prove smoking caused lung cancer and the science was not settled. And they were right. After all, we all know someone who smoked well into their 90s. But we all know that the probability of dying from lung cancer is significantly higher if we smoke. No one doubts that any more.
And the irony is, the science behind climate change is far more settled than the science behind the connection between cigarettes and lung cancer.
For example, a 2004 study published in Science magazine (a peer-reviewed scientific journal) evaluated every peer-reviewed science journal article published in the previous 10 years that dealt with climate change. Of the 928 articles randomly selected for review (representing 10 percent of the total number of articles), 75 percent either explicitly or implicitly accepted the finding that the planet was heating up and our reliance on fossil fuels was the cause. The other 25 percent of the papers dealt with other issues, taking no position on whether climate change was man-made. None of the papers disagreed with the finding that climate change was happening.
A 2013 follow-up study of over 12,000 peer-reviewed abstracts on the subjects of "global warming" and "global climate change" published between 1991 and 2011 found that of the papers taking a position on the cause of global warming, over 97 percent agreed that humans are causing it.
So if the science is so settled, why does the public think there is a raging debate among climate scientists? The answer lies in the skill of the denial machine that has convinced the media to give it equal time, as if their 3 percent deserves the same attention as the 97 percent.
For example, a 2004 study conducted (Boykoff and Boykoff) evaluated all articles published in the previous 14 years on climate change in four major newspapers: The Washington Post, NY Times, LA Times, and Wall Street Journal. Of a random sample that totaled 18 percent of all the articles (636 articles), more than half (53 percent) expressed doubt as to the cause of global warming.
In other words, there is no debate in peer-reviewed scientific journals; the debate is in the popular press, which has confused the public, making them think scientists are uncertain by giving equal time to the scarce few outliers. Which is exactly what the denial industry wants and is a tactic it has used quite successfully for many years. Their strategy is to convince the public that climate science is not settled and not all scientists agree the planet is heating up and that carbon pollution is the cause.
There is good evidence that strategy exists.
A 1998 memo developed by participants from Exxon Mobile, Chevron and the American Petroleum Institute (among others) memorialized an Action Plan on climate that claimed "victory will be achieved when " the average citizen and the media understands there are uncertainties behind the science.
Four years later, Republican communication strategist Frank Luntz (who has since accepted the science of climate change) advised Republicans: "Should the public come to believe that the scientific issues are settled, their views about global warming will change accordingly. Therefore, you need to continue to make the lack of scientific certainty a primary issue in the debate."
Both strategies were taken directly from the playbook of the tobacco industry.
In every scientific question, there will be outliers. There are scientists who don't think HIV causes AIDS and scientists who think vaccinations cause autism in children. These outliers have largely been discredited, but the press continues to give them print as if their views have the same merit as the overwhelming number of scientists who are on the other side.
Given the ability of climate deniers to get equal time in the media and their strategy of sowing uncertainty, it's no wonder the public gets confused about science.
— Ed Perry is the Pennsylvania Outreach Coordinator of the National Wildlife Federation's Climate Change Campaign.