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Catastrophe and the Climate

The Place of Science in the Policy Debate

Science indicates that climate change is happening but says little about how well civilization will deal with it. In my recent article (“The Problem with Climate Catastrophizing,” March 21), I argue that those I term climate catastrophists—observers who regard climate change as an unprecedented, existential threat—badly underestimate humanity’s capacity to cope with change and thus overreact to the problem. Michael Mann’s response does not so much refute this argument as disregard it (“Climate Catastrophe Is a Choice,” April 21).

Mann begins by writing that "rather than assessing the legitimate range of views regarding climate change, Cass marshals a series of fallacies." But he points to no mischaracterizations of climate science in my essay. Instead, he extends a kind of scientific confidence to issues that lie outside of science’s domain. “It is true,” Mann writes, “that the projected effects of unmitigated warming might objectively be characterized as catastrophic.” But “true” and “objective” science describes effects in the physical world; a view of the human consequences of climate change and whether they constitute catastrophe requires economic and social assessments. More strikingly, Mann argues that I dismiss

“some scientists’ concerns about climate change as instances of ‘motivated reasoning.’ But science represents the opposite of that process: as the physicist and science communicator Neil deGrasse Tyson has put it, science is ‘true whether or not you believe in it.’”

Because “science” is true, this claim suggests, “scientists’ concerns” are beyond reproach. Yet scientists’ concerns about the societal consequences of climate change deserve no special deference. In many cases, after all, such concerns are neither based on the scientific method nor draw on unique expertise. In turn, far from being out of bounds, the unresolved question of climate change’s economic and social effects should be central to a reasoned policy debate.

The problem is less that Mann is unpersuasive in bridging the gap between scientific findings and the possibility of civilizational catastrophe and more that he doesn’t try to do so.

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