Phillip W. Magness

Historian – 19th century United States

A Global Warming Thought Experiment

I generally accept that the planet is getting warmer, albeit at a more gradual pace than the politicized models of global warming alarmists suggest. Far from a cry to action though, acceptance of this fact warrants little more than a “so what?” If you doubt me, here’s a little historical thought experiment to consider:


The first functional modern thermometer was invented by Daniel Farenheit in 1714. Though an important scientific breakthrough, it would take over a century before his thermometer’s successors were deployed in sufficient number and range to produce something approximating a consistent time series of surface temperature data. Such measurements generally do not predate the 1880s. While scientists are able to reconstruct older temperature records from proxy measures like tree rings and ice cores, one less noticed implication of the thermometer’s relatively recent invention warrants mention: human beings had no systematized measurement of temperature variation for the majority of recorded history.

Now for the thought experiment. Suppose that, by a strange accident of history, the thermometer was never invented. No temperature scale was adopted, and no device was ever deployed to systematically measure temperature variations over time. In our imagined thermometer-free world, temperature would still vary in ways that attracted notice – both through the changing of the seasons, and in differences from year to year. This variation would be primarily experiential, evaluated by spot comparison to a previous day or even a descriptive record of years past. It would not be measured or quantified though.

In such a world would we even know that there has been an overall warming trend for the earth over the past ~200 years? Would we even know that global warming exists as a distinct pattern that could be differentiated from random year-to-year variations overlaid upon expected seasonal weather variations? Would we consider any of those observed patterns to be a “problem” in need of immediate and coordinated global remediation?

I’d wager that no, we would not notice. Without a set of thermometer readings, human beings would not notice an overall rise in temperature over this period. Nor would we causally attribute particular weather or even social and political events to “climate change,” though we would likely still fault individual periods of disaster for their direct effects. There would almost certainly be no coordinated political effort to “reverse” global warming, as knowledge of the long term warming trend would not even exist. And there would be no doomsday predictions tied to any of the aforementioned.

Our thought experiment points to an interesting conclusion about the role of “climate science” in shaping prescriptive policy actions. It basically illustrates that the present global warming scare is entirely a relic of our relatively recent ability to start measuring global temperature variations. Without knowledge of those measurements, it is highly likely that an aggregated record of non-thermometer descriptive weather observations would be perceptively indistinguishable from completely random variations over a prolonged cyclical weather pattern. And as most events that are causally attributed to global warming have more pronounced and measurable connections to other causal events, no reason would exist – absent the existence of thermometer data, which again is a relatively recent invention in the grander scope of human history – to believe that global warming was at fault. This suggests that the “climate action” movement is not actually responding to any tangible effect of global warming itself, but rather the production of data that suggest an otherwise unobserved and unnoticed phenomenon is happening.

About The Author


Comments are closed.