I received this email from Rob Fishman at the Huffington Post. My answer follows.
I’m the social media editor here at HuffPost (and a Cornell alum). I came across your blog online. I’m thinking of writing a piece about climate skeptics who hold positions at Ivy League (or comparable) institutions. Richard Lindzen came to mind after the recent Times article. I’m wondering if you have — or would know how to go about getting — a thorough list of professors at prominent universities who are also climate skeptics.
I’ve been thinking about how to best answer your question, which is not an easy one. First, I haven’t any firm idea what a “climate skeptic” is and I bet you don’t, either. You can’t possibly mean a person who is skeptical that the climate changes—for it always has changed, and presumably always will. I know of no scientist who doubts this. Beyond that, every scientist is skeptical, in varying degrees, about theories and predictions of change. The amount of skepticism is roughly proportional to the complexity of the forecast, how far out into the future it is for, and the strength of the forecast mechanisms (theory, data, computational schemes, etc.).
Nobody doubts that humans influence the climate, but there is a wide range of beliefs about how much. It is important to keep separate three things, which in this politically charged atmosphere even climatologists sometimes forget to do We have uncertainty in:
(1) the magnitude, timing, and location of changes;
(2) the changes to systems caused by climate change;
(3) and our ability to mitigate unwanted systems changes and to exploit desirable systems changes.
A system might be glaciers, or the range and number of a species, banana production, or land-use patterns, etc. Really, anything that isn’t temperature or precipitation. To show you how nutty things have become, most civilians and even many climatologists confuse (1) and (2). For example, if a climatologist measures a temperature increase (1) at, say, the north pole, then of course more ice will melt (2). But seeing ice melt is not evidence of (1).
I mean, a climatologist might have a theory why temperatures increased at the north pole (1). Seeing that temperatures have increased is evidence that his theory is correct. But noticing that more ice melted is not additional evidence that his theory is correct. It only means that ice melts when it gets hot.
Most times climatologists don’t measure a change, they predict one. A prediction, until it is verified, is not evidence that the climatologist’s theory is true. I want to repeat that because I have a difficult time convincing civilians this is so: a prediction, no matter how dire, does not mean the climatologist’s theory is true. It is zero evidence for his theory.
Suppose a prediction says that, say, temperature will increase in a region by a certain date. If temperature does increase, then this is some evidence that the theory that led to the prediction is true. But it is not complete evidence: other mechanisms unknown to, or not liked by, the climatologist might have caused the increase.
But if the temperature does not increase, and even has the audacity to fall, then this observation is evidence that the climatologist’s theory is false, or at least badly broken. This is where we stand today, at least with climate forecasts.
The situation is actually far worse. Many people take the predictions of climatologists and use them as input to their own forecasts of various systems changes. When these forecasts are in the direction of the undesirable, people—even climatologists—use this as evidence that the climatologist’s theory is right. This is crazy. The two things are unrelated logically. They have nothing to do with one another.
Most of these systems forecasts are statistical, incidentally. I have seen many, and all are awful. There is a strong element of sloppy bandwagon research here. In a way, it’s hard to fault the researchers: they are rushing to where the money is. But they are often outrunning their brains.
In any case, I will repeat: a dire systems forecast (that uses as input a changed climate) is not evidence of climate change. It just isn’t. To claim a plague of frogs will befoul us unless “something is done” is not evidence that the climate will change untowardly.
What about point (3)? It is usually assumed, without proof, and against all evidence to the contrary, that there will be no way we can mitigate against unwanted systems changes without, naturally, spending of lots of our money. It’s not that having to spend money isn’t a possibility. It is. But to argue that it be spent while we are still so uncertain of what will happen without mitigation is crazy. Finally, no matter what we know about (3), it is not evidence that a climatologist’s theory is true or false.
Once more, it’s worse. There have been hundreds of “studies” purporting some evil if temperature increases. There have been hardly any or none arguing for benefits. It is logically possible that climate change will only be harmful (to humans and other picturesque species), but it is infinitely unlikely. To argue otherwise is to ignore selectively massive amounts of information.
Our uncertainty is (2) is large, as is our uncertainty in climate predictions (1). I hope I have made myself plain here. We first need to have better certainty that climate models can make skillful predictions (which they so far have not demonstrated an ability to do), before we can consider scenarios in (2) or (3). It’s true climate models (somewhat reasonably, and only in a statistical sense) can represent past climates. But the proof of the model is always in its ability to predict new data (i.e., the future). We still await this proof.
What’s a citizen to do? Well, it takes years (and years) to become an expert in any of these areas. Very few civilians thus have the ability to independently assess the evidence, so all you can do is to poll scientists and ask them what they think. But civilians are too readily trusting scientists here (by making the kinds of errors I outlined above). Why is that? You can probably answer that better than I can. All I can offer is that many like to think the worst.
I don’t think there is any use in appealing to authority by saying, “This many Ivy League scientists have an average skepticism of X%” Besides being unable to define this average skepticism, you have to keep in mind that those who edit the journals, award the grants, and chair the academic departments are mostly convinced that their theories are true. All the believers in a theory naturally club together and support each other. This is human nature. It only becomes absurd when that group of folks point to critics and say, “They can’t be trusted because they are not one of us.” I’ll leave you to name to logical fallacy in that argument. Hint: it’s a common one.
My advice is to forget citing numbers for and against, and try instead to find the best arguments for and against. Put these arguments to leading proponents and ask them to honestly answer this question, “How can you be wrong?” Scientists are, of course, always supposed to do this, but there are plenty of examples in the history of thought which prove that this simple question has been forgotten.
Please feel free to ask for clarification. I have caught a nasty cold and my head is not clear, so I have probably explained some things badly.