Despite the climate emergency, climate disinformation actors keep broadcasting infodemic content to millions of people. Here we use semantic patterns to unveil emotionally distorted content linked to polarization. Mindset reconstruction with forma mentis networks exposes the emotional backbone of language, and such exposure highlights the attitudes towards “climate change” fueling the climate divide. Greta Thunberg’s speeches, combining anger (towards inaction), fear (of an approaching threat) and trust (in solving this crisis), perceive “climate change” as an indispensable “call-to-action” fight. This makes climate activism’s mindset entwined to revolutionary emotions. In comparison, the emotional profile adopted by climate disinformation actors shows conceptual associations and emotions indicating that climate disinformation promotes hypercritical skepticism, hiding under a generally trustful promotion of (climate) change and including: (i) discussing numbers in terms of imbalanced exaggerations, (ii) referring to scientists in a stereotypical way, i.e. isolated individuals that attempt to provide abstract, theoretical evidence to climate disinformation, (iii) displaying negative emotions against children, and (iv) showing fear against public policy interventions. Through this hidden cognitive dissimulation, climate disinformation can greatly inhibit social activism and, consequently, policy making addressing climate change. Cognitive tools exposing distorted emotional content should be adopted to foster pro-active climate debates.