That article doesn’t argue for any sort of causal relationship between climate change and racism. Rather, it argues that a similar kind of denialism in the face of facts undermines the notion of shared truth by further entrenching people within their (a priori) belief systems.
Put another way, Kendi is pointing out different manifestations of the dangers of equating (dis)belief with knowledge.
Put another way, Kendi is pointing out different manifestations of the dangers of equating (dis)belief with knowledge.