I went to a live version of the Not Another One podcast last night (13th November 2024) at the John Smith Centre in Glasgow, with Steve Richards, Miranda Green, Iain Martin and Tim Montgomerie. It was a good evening where, in the wake of Trump, climate change came up. Afterwards, I talked to two of the panellists—Tim and Iain–to try to understand why they are not completely on board with the need for us to act now and act big.
I'm not sure my arguments really convinced them, but I thought I'd try to write down, succinctly, what I think people need to understand (but might not) about climate change and the broader, interlinked ecological crises. I'm not going to cite things here point by point, but most of this can be verified by reading even the summary of the most recent IPCC report.
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Climate change is real.
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Climate change is primarly human generated (“anthropocentric”). Believing that human activity isn't the main factor behind climate change at this point is like believing smoking doesn't cause cancer.
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The greenhouse effect is really simply physics that is very well understood. The increase in carbon dioxide (and other greenhouse gases) from around 280 parts per million to about 420 parts per million today is the mostly result of human activity, and carbon dioxide stays in the atmoosphere for hundreds of years.
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Climate change is non-linear, i.e. adding 1% more carbon dioxide can cause changes much bigger (or smaller; but probably bigger) than 1%.
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There are critical thresholds (“tipping points”) in the system. When we pass these thresholds, it is often extremely hard or practically impossible to go back. The most obvious of these are things like melting the permafront. An enormous amount of methane (a greenhouse gas more than thirty times as potent as carbon dioxide) is trapped in the permafrost and as that melts the methane is released and is not going back even if we cool the planet again. This is an example of a positive feedback loop that makes the climate response to our action non-linear. Similarly, the ice caps are unlikely to reform once gone and they reduce heating by (among other things) reflecting a lot of sunlight.
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1.5°C (2.7°F) does not sound like much, but it is, and warming is already around this much above pre-industrial levels. We are nowhere near being on track even to limit warming to 2°C. 3–5°C (5.4–9°F) is more likely, 8°C (14.4°F) is quite possible.
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There are large uncertainties in the size and speed of change, partly because of all the nonlinearities and feedback loops (positive and negative), and partly because we don't understand everything. But it looks bad, and so far change is happening towards the faster end of projections, rather than the slower end.
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The sun provides enormous amounts of free energy that we can use safely without causing heating. Even if fossil fuels were not causing warming, alternative energy is cleaner, safer, less polluting and does not involve using up finite resources to the same degree.
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One of the arguments against taking (more) action I heard was that there's no point because of China and India. This is an odd argument from conservatives. As Edmund Burke said: No one made a greater mistake than he who did nothing because he could only do a little. Not only are small reductions worthwhile in non-linear systems, but there is a multiplier effect from leadership. And the science is right.
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Climate change is driving and will drive resource wars and mass migrations, with hundreds of millions of people simply unable to live in the worst affected areas.
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It is much cheaper to prevent (ameliorate, reduce the rate of) climate change now than to try to remediate it in the future.
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Climate change is intimately linked to other ecological crises, including species loss. We are losing species at a completely unfathomable rate, possibly as fast as during the major extinction events. We don't know where the threshold are that tip species into extinction, and we don't even know all the species being lost. Ecosystems are called ecosystems because they are systems, and we depend on them to keep the Earth in a state capable of supporting human life. Destroying species and ecosystems as fast as we are is reckless and stupid even from the perspective of human self-interest. We really need the bees and all sorts of other, less glamorous species, possibly including unknown species.
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The Stockholm Resiliance Centre tracks 13 planetary boundaries the breach of any of which is considered unsustainable. In 2023, nine of these had been assessed and six have already been breached. This doesn't mean we are doomed or that human extinction is imminent; but we are making human life on Earth much harder to sustain.
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Tim said he thought the only hope was that AI will save us (and he wasn't hopeful). At the moment, there is little doubt that the main impact of LLMs and generative AI is that it is consuming enormous of power, adding to warming. Some of that comes from clean energy, and some even comes from purpose-built clean energy, but much of it doesn't, and the clean energy could be used to more productive ends than LLMs. I believe in the potential of AI (though less in the potential of LLMs), but pinning our hopes on a completely vague idea that “maybe AI will come up with something” is wishful thinking.