Nick Lyth, April 2024
Rethinking Climate Change Predictions: Insights from Simon Sharpe
I was recently lucky enough to hear a talk by Simon Sharpe, author of the radical and fascinating Five Times Faster (Pub. April 2023, Cambridge University Press). I recommend it to your attention unreservedly.
He shared a fundamental observation that transforms our perspective on Climate Change science. We are operating in an analytical framework by virtue of which the scientists have demonstrated the impact of carbon concentrations on global temperatures. These are now observable and measurable. So far, so good. However, they have then extrapolated from the trends to predict how these will affect the world’s climate over the next years, decades, and even centuries. They have been doing this for more than thirty years. While the predictions have largely been right, sadly for all of us, they have always been more optimistic in judging the effects of their predictions than was born out by subsequent events. One example has been the risk of passing tipping points in the climate system. We have seen repeated revisions in the IPCC assessments of higher risks at lower temperatures, showing the tipping points closer to us than previously expected each time.
Simon Sharpe shows us that while predictions of this kind are useful, these repeated revisions are an indication of what scientific method is missing. It makes no allowance for risk, or risk assessment, which is the tool to help us decide what we want to avoid, and how much we want to avoid it. Science is much less effective in considering variables. It uses empirical observation to predict, from which conclusions are drawn. I bounce the ball on the ground nine times, and it reaches a height of two feet. I conclude that it will reach the height of two feet when I bounce it a tenth time.
The scientific process is useful and has helped in the development of some of our world’s most effective and useful technology. Science should not be castigated for its methodology. But it should not be used as the prime guide to strategic decisions in circumstances for which the methodology is incomplete, and lacks an important dimension.

