Term originates from an article I remember seeing a while ago. Some excerpts:

These two questions—of sovereignty and of capitalism—point toward four rough paths. We call these Climate Leviathan, Climate Mao, Climate Behemoth, and Climate X. Climate Leviathan describes an emergent global order committed to the consolidation of capitalism via the organization of a form of planetary sovereignty that can overcome the collective action problem. Climate Mao would represent a similarly planetary-scale “solution,” but one dedicated to an anti-capitalist order. Climate Behemoth describes a global arrangement animated by a chauvinistic capitalist and nationalist politics that denies—until it can only denounce—the threat climate change poses to national capitals. Climate X is the name we give the collection of movements that pursue global climate justice: movements that build non-capitalist political economies, and construct solidarities at multiple scales that reject the political logic of sovereignty.

All these regions [in The Global South] have their own political-economic, ideological, and cultural histories to draw upon, many of which do not include a commitment to the regulative ideal of liberal-capitalist progress. This is the reason we give the name Climate Mao to the third future trajectory: a non-capitalist order of Leviathan-like planetary sovereignty. This is not the same thing as “Climate China,” although it is hard to imagine a scenario in which China does not play an important role in global climate politics. Instead, we call it Climate Mao partly because we anticipate that the potential for this future lies in the radical political traditions of South and East Asia, regions with historically significant rural collectivism that retains substantial contemporary organizational resources. Since this part of the world is home to literally billions of poor people, the vast majority of whom climate science indicates live in communities immediately at risk of climate change–induced disturbance—more at-risk populations than anywhere else on Earth—it seems reasonable to expect that these masses will draw upon those political and ideological traditions in the face of threats to their livelihoods. Given that climate change threatens not only the internal stability of these regions but the global political economy to which they are increasingly central, we anticipate Climate Mao would not embrace the nation-state as the locus of sovereignty, at least not for long. Insofar as capitalism stands justifiably accused of both driving climate catastrophe and preventing serious action to address it, Climate Mao represents the most likely non-capitalist formation willing to confront Leviathan on the planetary stage.

The appeal of Climate Mao to radical critics of capitalism continues to strike us. Since it is clear to them that the capitalist nation-state has proven an irremediable obstacle to climate action, let alone anything approaching climate justice, the appeal of Climate Mao is almost visceral. Like Leviathan, it promises to get beyond the spatial and political limits of the state and do something. But unlike Leviathan, it will not be beholden to the planet-eating capitalism that generated the problem in the first place—a condition that appears certain to guarantee Leviathan’s inadequacy to the problem.