Who speaks authoritatively about climate change? What role, in particular, do social scientific experts play in the conversation? This second question in particular is a key part of my next big research project on debates over the costs of climate change. Today, I was delighted to read a new paper by Maher et al that presents an incredibly useful new and freely-available dataset of testimony offered at congressional hearings in the U.S. by social scientists. Making use of their data, I was able to get a little bit of insight into one piece of this question. Spoiler: not that many social scientists have testified before Congress about climate change, but those who have are overwhelmingly economists.
First, the original paper. Maher et al mostly report on the construction of their dataset, which involved a combination of automated and hand-coding techniques applied to the metadata available in ProQuest’s database of congressional hearings from 1946-2016. They then use these data to track the relative proportion of congressional testimony coming from the different major social sciences, as well as some trends in where those social scientists are located (academia, government, think tanks, or organizations like private businesses). Here’s are two charts that summarize two main results. First, economists dominate the conversation, having more than double as many testimonies as the other major social sciences combined.
Second, those economists are mostly academic in the early period but come increasingly from other places, with think tanks equalling or surpassing academia starting in the mid-2000s.
Using this data, I pulled out just those testimonies at hearings that included in their title the terms “climate”, “greenhouse”, or “global warming” (a fairly standard way if quick way to identify conversations about climate change, which climate change being used more recently, and global warming and greenhouse effect being used in older discussions). Doing so yielded just 76 testimonies. Of those, according to the data, 58 come from economists (about 3/4 of the total), 16 from political scientists, 1 from a psychologist, and 1 from a sociologist. That last one at least is a data error though – the testimony comes from the climate scientist Michael Mann, not the historical sociologist Michael Mann. And it’s possible a couple of the others are false positives as well. (There’s no easy way to address false negatives with the publicly shared data as it only includes the testimonies flagged as social science.)
Of the 58 testimonies by economists, 9 are from those affiliated with think tanks, 4 from the Council of Economic Advisors (including two by Treasury Secretary nominee Janet Yellen!), 5 from the Congressional Budget Office, and 16 are primarily affiliated with academia. The remaining 24 coming from various for-profit companies (e.g. Shell), and non-profits and lobbying groups not coded as think tanks (e.g. American Council on Capital Formation, American Petroleum Institute). To my eye, most of these come from organizations you might classify as part of the denial & delay movements – that is, they advocate consistently against the reality of climate change or the need for climate change action.
That’s it for this first pass through the data. One next step is to pull all of these testimonies to see exactly what economists are offering in these testimonies. Another is to get a sense of how many testimonies there are about climate change in total – one limitation of these data is that you don’t get a sense of the space of all testimonies for comparisons to non-natural scientists (though Maher et al usefully report that social science testimonies are about 1.8% of those in the full corpus). My suspicion is that even though economists outpace the other social sciences, these 58 testimonies represent a tiny a tiny fraction of the congressional climate change conversation.