The Core

James Lovelock: 'Enjoy life while you can: in 20 years global warming will hit the fan' | Climate crisis | The Guardian
https://www.theguardian.com/theguardian/2008/mar/01/scienceofclimatechange.climatechange

Interesting that popped up for you.

Well, he gets more right than most prognosticators. He died in 2022, so we can't ask him directly how he would update this. This paragraph stands out though:

QuoteNuclear power, he argues, can solve our energy problem - the bigger challenge will be food. "Maybe they'll synthesise food. I don't know. Synthesising food is not some mad visionary idea; you can buy it in Tesco's, in the form of Quorn. It's not that good, but people buy it. You can live on it." But he fears we won't invent the necessary technologies in time, and expects "about 80%" of the world's population to be wiped out by 2100. Prophets have been foretelling Armageddon since time began, he says. "But this is the real thing."

His take on nuclear and renewables is the thing he gets most wrong. There was a long time that a certain subset would scream, "what about nuclear!"

I thought I posted this here, but I can't find it.

Reactors Have a Surprising Amount of Detail
The more difficult your mission, the more the details are critical to understand

The handwavy, "just build more reactors" takes are mostly from people who are not nuclear engineers. The challenge of launching small-scale nuclear has been much less tractable than early proponents suggested and industrial-scale nuclear like we knew in the 1950s to 1970s is basically unbuildable in most of the world today (cost, NIMBYism, etc).

Meanwhile, the cost of battery storage is falling at rates Lovelock couldn't have imagined.

>> Quorn

Quorn is not "synthesized" food - it's a food made from fungus. They got sued because they originally said it was from mushrooms, which it isn't, but it is from fungus, which is used in all kinds of foods (like Roquefort and Gorgonzola and tempeh) and is not "synthesized" in the sense that's normally meant. Now, of course, most people like it less than the chicken it is meant to resemble, but actually, I don't like chicken so I kinda like Quorn. But it is most definitely an ultra-processed food. Still, that's not the same as "synthesized," whatever that means.

>> 80% of the population wiped out by 2100

I won't be around to say one way or the other, but I'm going to guess that is wildly pessimistic.

We are at about 8b right now. At the low-end, the UN projects 7.3b by 2100, assuming no catastrophe. Now, we have had catastrophes that have wiped out up to a third of the population, such as areas hit by the Black Death. But 80% levels would be... a lot.

The Irish Famine resulted in about a 45% population decline over sixty years, but that was the result of an excess mortality of about 13% because most of that population loss was emigration and then lack of reproduction. In any case, that's the biggest decline in the industrial age.
https://www.bostonfed.org/-/media/Documents/conference/46/conf46c1.pdf

Will population loss on the entire planet equal ~1.8X the greatest regional population decline for which there are good numbers?

To find population loss reaching or exceeding 80% you have to go back to the invasions of the Americas in the 16th-20th century and possibly the "genetic bottleneck" period of 50K-100K years ago.