Easy to measure, hard to model

Alex Epstein spends much of this video picking apart a statistic that is meaningless to the climate debate. He goes to great lengths to add uncertainty to the widely-quoted “97%” figure, and then makes an illogical leap. If this statistic is inaccurate, Epstein would have us believe, no “anti-fossil-fuel” science can be credible. He spends nearly a third of the video discussing hypothetical (that is, entirely made-up) vaccine statistics in emotionally charged language, as a distraction from the climate science debate.

Let’s start with something true that Epstein admits: the amount of CO2 in the atmosphere has increased significantly over the last century. There’s no scientific debate about this. Concentrations of CO2 and other greenhouse gases in the atmosphere are easily measured in modern times. There’s also little scientific doubt that fossil fuel usage is largely responsible for this increase – geologic processes don’t move that fast. Epstein cites a study that looked at exact wording in scientific papers to cut down the “97%” figure, but ignores the obvious general agreement among scientists on measurable data.

So if the levels of CO2 are well understood, where is the debate? What Epstein glosses over are the effects of more greenhouse gases, about which there is significant uncertainty. Climate processes on the Earth, and their local effects that we see as weather, are an extremely complex mix of systems. Scientists are the first to accept that ocean currents, cloud cover, land usage, and hundreds of other factors are hard to model. That doesn’t mean the science is wrong, only that the Earth is very complex! Despite the difficulties in predicting the effects of more CO2, we are seeing many of these measurable predictions coming to pass in the last twenty years – things like stronger storm seasons, more devastating fire seasons, and shifting crop patterns. Rising sea levels threaten an enormous amount of destruction to sea-level cities where hundreds of millions now live. Scientists don’t universally agree on exactly what will happen, but most agree the effects will be widespread and could be devastating if we’re not prepared.

Another piece of truth from Epstein is that fossil fuels enable our standard of living and helped build the world as we know it. Yes, and there’s nothing wrong with appreciating the modern comforts we have built for ourselves! Epstein makes the entirely false argument that if climate scientists don’t universally agree on the exact wording in their studies, they must be against all fossil fuel use. This is a simple attempt to equate two different things. To quote Epstein himself, talking about unrelated issues “tells us nothing about the meaning or magnitude of climate change.”

The point of the 97% figure is not whether 95% or 99% of climate scientists agree on specific effects of increased atmospheric CO2 – they don’t. But it’s a scientific fact that greenhouse gas concentrations are increasing. Humanity has a large and very expensive problem facing us as we get further into the 21st century and experience more of the certain effects of climate change.