Climate skepticism decreases when the planet gets hotter and conservative support wanes

Identifying historical patterns of fluctuation in climate change skepticism guides researchers, policy makers, and science communicators in efforts to catalyze change in the future. We analyzed data from 25 nationally representative polls collected in Australia from 2009 to 2019 (N = 20,655). Although it remains concerningly high, climate skepticism trended down in that 10-year period, particularly among conservatives. Multilevel analyses identified two variables that stood out as being relevant in explaining that trajectory. First, climate change skepticism was positively associated with support for conservative political parties in national polls. Second, climate change skepticism was negatively associated with the annual global temperatures the previous year. There was little evidence that climate change beliefs were associated with economic variables or with seasonal variations in temperature. Furthermore, there was only weak evidence that climate change beliefs were associated with national temperatures. This suggests that global temperatures in the previous year are impactful because of their informational value (as a communication heuristic for the urgency and immediacy of climate change) more so than for their experiential value (in the sense of people actually experiencing warmer weather). Importantly, the effect of previous global temperature was particularly pronounced among those with the strongest levels of skepticism: political conservatives. This suggests that rising global annual temperatures have the power to update beliefs among those most in need of converting to the climate cause.