How Science Works

            The previous post ended with a question: Why do we not hear more about climate change from our political and economic leaders and in the media? There are many reasons. The fossil fuel industry has purchased the silence of our politicians; the silence of the news media (have you seen coal, oil, and natural gas commercials on the morning news shows?); and the scientific testimony of a few highly unethical “scientists”. The most notorious of these paid “denialists” is Richard Lindzen, a faculty member at MIT. He is paid by the oil industry to discredit climate science, just as he was paid 50 years ago by the tobacco companies to discredit science supporting the link between smoking and cancer. Richard Lindzen is a despicable human being, but he and others have been effective in confusing the American public and the political establishment about the reality of climate change. Among their arguments is the claim that there is a conspiracy of climate scientists to produce data supporting climate change in order to retain their research funding. This argument is advanced in Crichton’s book, “State of Fear”. To one who knows how science works, this is a ridiculous conspiracy theory.
            So how does science work? The training of a scientist begins in high school, continues in undergraduate university, and usually culminates in a Ph.D in a highly specialized area (for example, I loved chemistry in high school, majored in Chemistry at Purdue, earned a Ph.D in Inorganic Chemistry at the University of Illinois). During this time, the blossoming scientist is trained in data acquisition and interpretation, detailed record keeping, and the long tradition (since Kepler, Galileo et al) of scrupulous adherence to moral and ethical standards. I’ll bet that not more than 1 incipient scientist in a thousand has even a fleeting thought about “cheating” (that is, manufacturing data—numbers—to support some preconceived theory). The reason for this is that science is a peer-reviewed activity; an activity in which error is relentlessly sought and expunged; an activity that is self-correcting. This works as follows. A research scientist at a university or a government agency (such as James Hansen at NASA) collects data in an investigation of some aspect of his/her area of expertise. This might be, for example, temperature data from a number of thermometer stations worldwide. Data might be collected for a year, two years, longer. S/he might then combine this data with that of other scientists taken over a number of years prior, and observe, say, that the average temperature seems to be increasing year-to-year. The scientist writes up his experiments and analysis in a highly-referenced paper, which is submitted to a professional scientific journal (such as Science, or Nature). A journal editor makes copies of the paper and sends them to other scientists who are also expert in the field of the author (i.e., peers of the author). These peers study the paper, looking for error, and delight in finding it. They write their reviews and return them, and the editor relays them to the original author (with reviewer’s names excised). Because the reviews are anonymous, they are often quite rude and harsh. The author finds out in often unpleasant fashion that his paper is un-publishable unless he addresses the reviewers’ criticisms. Most authors do this, which may mean more experiments, more data, more analysis, amended conclusions, and so on. Eventually, a quality paper will pass this initial peer review and be published (a poor paper will not). Then the real fun begins. The paper is now “public”, and subject to the peer review of every scientist who is interested in the subject matter. They, too, absolutely delight in finding error. Some will want to use the data in the paper as a starting point for further research. They will certainly begin by attempting to reproduce some of the data in the paper to be satisfied that the original guy did his experiments carefully. Should they not be able to reproduce the first guy’s numbers, watch out! This will become widely known and thus investigated by others, and if the data or conclusions are faulty, they will be dismissed out-of-hand. This is the self-correction of peer review. Please realize that the first scientist did not intentionally publish faulty data. In all likelihood, the data were collected by graduate students who may have made errors in designing and carrying out their experiments. These were not purposeful either; they are simply mistakes. But the mistakes will be found.
            The idea of a conspiracy among scientists to manufacture data supporting climate change is silly because, first, a substantial number of scientists would have to agree to abandon the morality/ethicality that has been built into them for years; would have to somehow arrange that no scientist outside their conspiring group be asked to review a paper (also requiring the editors to be involved); and would have to manufacture mutually consistent data, so that some targeted climate change issue (say global warming) would be supported. Surely there would have to be a few email communications among them in which it was decided who would produce which numbers, and what the numbers should be. Oh, well, it’s ridiculous!