This is the text of a Letter to the Editor that I’ve just submitted.
Heather Hanes is wrong about the research project being initiated at the University of Regina (SP, June 16, 2014 “U of R begins pesticide research study”). They don’t have a hypothesis. They have an agenda. Tanya Dahms admits that the goal is to eliminate pesticides. Her tone implies that they are simply going through the motions to gather evidence of what they already assume to be true. A real scientific inquiry would ask “How does pesticide use affect plant populations in a grass lawn?” It is possible that killing dandelions and other noxious weeds allows non-weed species to flourish. No one can know until the study is complete and even then they might have no useful answer since two test plots is a tiny trial and the researchers are obviously biased.
You’ve probably heard the statistic that 97% of climate scientists agree that humans are causing global warming.
Have you asked where that number comes from? Is it true? The source is a paper by Cook et al. and, no, it is not true.
First, the 97% stat is the percent of abstracts expressing a position on AGW that implicitly or explicitly endorsed it. However, 66% of all abstracts reviewed expressed no opinion on AGW. A recently published review of the Cook paper found “just 0.3 % endorsement of the standard definition of consensus: that most warming since 1950 is anthropogenic.”
Second, the 97% is of abstracts not scientists. Abstracts are brief summaries of papers. To really understand a study, you have to read more than just the abstract. Each abstract can have multiple authors who may or may not agree with every conclusion in the paper so you can’t even just multiply the number of papers by the number of authors.
Relying on published abstracts is also biased. Challenging a popular position means that research is less likely to be funded and papers are less likely to get published. To know what scientists believe about any topic would require asking them in a systematic, unbiased, anonymous manner.
And even then consensus doesn’t matter. 99.999% of people believing something does not make it true. For example, physicians used to believe that gastric ulcers were caused by spicy foods and stress until two Australian scientists proved that most are caused by H. pylori bacteria.
TL;DR: No AGW consensus and consensus doesn’t equal fact.