This paper explores ways in which applied semantics (coming out of Natural Semantic Metalanguage approach) can inform effective communicative strategies for action on climate change. After framing discussion, it presents three case studies, which are intentionally disparate in nature: contrastive semantics of the expressions 'climate crisis', 'climate emergency', and 'climate catastrophe'; a semantically-enhanced examination of how public inquiries into extreme weather events help shape climate discourse in Australia; the semantics of 'the economy' in everyday English and the implications for climate change discourse. We argue that climate action communication is clearer, more resonant, and more effective when it uses or builds on ordinary words and local meanings.