Noise, uncertainty and weather

In The Primacy of Doubt: From climate change to quantum physics, how the science of uncertainty can help predict and understand our chaotic world (2022) Tim Palmer, weather mathematician and physicist, explores a set of issues related to uncertainty. It is a great read, even if it gets technical in places, because it tracks the author’s own questions and research issues. As such the book reads as a research journal in places, with personal remarks on things like consciousness, decision making and the question of religion and spirituality.

Palmer starts from weather, and the problems of predicting weather that has faced humanity for a long time. He chronicles the move from historical patterns as the basis of prediction to complex grid models and ensemble forecasting – showing how the best way to deal with uncertainty is to represent it well in our reports and research. The practice of showing projections with intervals of certainty is just one of many examples of what he considers should be much more widely spread practices, and it is hard not to agree with him.

It has become a tired cliche to say that a book is interdisciplinary, but Palmer’s book is that – or perhaps something better: it is a book that ignores the disciplines and explores a set of problems as if they make up their own discipline: the study of uncertainty at all levels, from quantum physics to the economy. Maybe discipline agnostic studies are more valuable than the so-called inter-disciplinary work that many seem to be paying lip service to – ignoring the disciplines rather than trying to navigate them is probably a better framing.

Palmer certainly does so – moving from weather prediction to the question of the ultimate nature of gravity (Palmer suspects it is not a force of the same kind as other fundamental forces of physics – and that there are no gravitons), he aims to show how uncertainty at all levels is key to understanding complex systems. He makes a convincing case for understanding uncertainty, and chaos, much better – and in many ways this book is the natural heir to Gleick’s work on Chaos – and perhaps best read with its predecessor.

It is a book to digest and come back to; there is much in here that is thought provoking – and many mental models get renovated in useful ways. Just one example, that really made sense to me: the idea of energy efficient rationality. Palmer notes that what we usually term biases are really just energy efficient ways of sort of solving problems in approximate ways where we do not want to expend the energy to get to the deeper answer. This, in turn, is eminently rational from an evolutionary perspective – since it minimizes the amount of energy we spend on problems that we perceived to be constructed or artificial.

The only thing psychology has access to study in the lab, with students, is energy efficient rationality, and all other forms of rationality must be inferred in ways that are perhaps better suited to the methods of someone like Gary Klein.

Palmer also suggests that there is a real and interesting role for noise to play in cognition and computing – and here I suspect that he is onto something quite important, as low voltage smaller circuits might become noisier, and if we see that as a strength and harness it we might be better off than if we try to minimize the noise.

Finally, it will be interesting to see what happens with the reception of Palmer’s book since he discusses climate change in a rather open way – attempting to seek out strengths and weaknesses in what he terms climate maximalist and minimalist theories. It seems clear that Palmer believes that anthropogenic climate change is a real thing and has potentially disastrous consequences – but he also notes that climate models are weak in many respects (they miss things like cloud cover negative feedback loops, he argues) and so there is a risk that he is read as a climate skeptic (which seems such a weird term, as he notes, since no one is skeptical about there being a climate?).

That would be a huge mistake – since there is a lot to learn from his discussion on climate change; not least in the discussion about cost / loss ratios and where to balance out. It seems safe to say that optimizing for energy efficiency, while acknowledging that no civilization reduced its absolute consumption of energy without perishing, is a stance that should be explored more.

All in all: 7/10 – and worth a re-read.

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