Gates’s memo that there is no existential climate crisis has given climate advocates conniptions. They now claim they never predicted climate doom—although they did, often—and that climate spending need not come at the expense of social spending (which it has, in the trillions of dollars). It’s magical thinking and easily falsified by politicians’ real-world decisions.
By Alex Trembath, The Ecomodernist, Nov. 12, 2025
We have long argued that climate change is one among many challenges facing human society, not the existential threat it’s often described as. In poor countries especially, poverty and public health are by far more serious concerns, where the best defence against climate change is economic development, not emissions reductions.
The Trump Administration has cancelled billions of dollars in funding for health and development for the poorest and most vulnerable people on Earth. In response, Microsoft founder Bill Gates has shifted his support from long-term innovation towards more immediate life-saving programs. It’s a zero-sum calculus, and a defensible one at that.
Gates recently articulated his updated views on climate change, an issue that has occupied much of the back half of his career. As he wrote last month in a widely covered memo, climate change “will not lead to humanity’s demise” and “the biggest problems are poverty and disease, just as they always have been.”
It’s understandable that Gates’s memo caused a conniption among climate advocates. But their chief complaints, thus far, are particularly unpersuasive. Having spent the last 20 years or so convincing policymakers to prioritize climate change, they’re now insisting that doing so need not come at the expense of other issues like public health. It’s magical thinking, and easily falsified by policymakers’ real-world decisions.
Climate activists have predicted end of human race—many times
In a press briefing hosted by Covering Climate Now, the climate scientist Katherine Hayhoe pushed back on Gates’ assessment of climate risk, arguing “I have not seen a single scientific paper that ever posited that the human race would become extinct … it’s a straw man, the way he’s proposing it.” My former colleague Zeke Hausfather also called this a “straw man,” arguing at his blog that the memo “needlessly sets up a conflict between laudable goals: we can both mitigate emissions and alleviate poverty, disease, and hunger.”
First of all, one should always be skeptical of arguments in which tradeoffs don’t exist.
Additionally, I’ve seen more than one scientific paper positing that the human race could become extinct due to climate change. This 2022 paper, published in the prestigious Proceedings from the National Academy of Sciences, describes the possibility of “potential human extinction” due to climate change as a “dangerously under-explored topic.” The authors aren’t obscure cranks: they include Johan Rockström, Hans Joachim Schellnhuber, Will Steffen, and other architects of the extremely influential “Planetary Boundaries” framework that Hayhoe has elsewhere endorsed.
I asked ChatGPT for 25 more examples of scientific papers positing that the human race would become extinct due to climate risk. After thinking for one minute and forty nine seconds, it readily provided these examples.
And that’s because the idea of climate change as an existential threat to humanity is incredibly widespread, within the scientific literature and especially outside of it.
Covering Climate Now, which hosted the webinar with Hayhoe and Hausfather, describes climate change as an “existential threat” on par with nuclear war. Hayhoe herself has argued that “Humans cannot survive without the rest of the ecosystems on this planet that provide everything we use.” In 2018 Greta Thunberg famously quoted a scientist who argued that climate change would “wipe out all of humanity,” arguing elsewhere that “there are no gray areas when it comes to survival.” One of the best-selling climate books of the last decade is titled The Uninhabitable Earth. I could go on and on.
The function of this rhetoric has been to raise the salience of climate change among policymakers and the general public. After President Obama “placed energy second on the priority list, guaranteeing health care would occupy most of the year,” as Bill McKibben lamented in 2009, climate activists set about reversing this prioritization for the next incoming Democratic president. And it worked. “It is the ultimate threat to humanity: climate change,” said President Joe Biden in 2023.
Now, it’s possible to argue abstractly that we can care about climate change without caring less about poverty and disease. But when we move from the abstract to the practical, these calculations become a lot more zero-sum.
Tens of billions of dollars that could have gone towards infrastructure, development, and public health was instead spent on reducing emissions in the poorest parts of the world.
And it’s not just Bill Gates. A 2023 analysis by CARE International found that “most of the public climate finance reported by wealthy countries is taken directly from development aid budgets.” The Breakthrough Institute’s Vijaya Ramachandran and her colleagues similarly found that most World Bank climate aid in poor countries goes towards mitigation, not adaptation. Tens of billions of dollars that could have gone towards infrastructure, development, and public health was instead spent on reducing emissions in the poorest parts of the world.
A dollar going to climate mitigation is a dollar not going to public health or poverty
“What world do they live in?” a frustrated Gates asked Amy Harder recently, in response to climate advocates’ criticisms of his memo. “This is a numeric game in a world with very finite resources, more finite than they should be.”
Gates is asking the right question here. It’s one thing to claim to care about climate change and global poverty in equal measure. And we’re a wealthy country, with many wealthy people, capable of funding many different things.
But when it comes to real-world philanthropic giving or public investments, the marginal dollar going to climate mitigation is in fact a dollar not going to public health, and vice versa. Philanthropists and politicians have to decide how much they care about each.
The fact that climate hawks are failing to reckon with these newer real-world tradeoffs is a further sign of their unwillingness to acknowledge the end of their era.
This article has been edited for length. For the original article, click here.