Climate-Related Content on Iberian Fact-Checking Platforms: Topics, Entities and Factual Authority in Polígrafo and Maldita

How is climate-related content produced on fact-checking platforms? This study addresses this question by analysing the climate-related content of two Iberian platforms, Polígrafo (Portugal, n = 26) and Maldita (Spain, n = 277). It combines topic modelling (LDA) and named entity recognition (NER) applied to 303 articles published between 2019 and 2025 with manual coding of the discursive functions of entity mentions. The material includes fact-checks and other editorial genres. The results reveal two contrasting editorial profiles in the analysed corpora that nonetheless share a common epistemic foundation. Both platforms anchor their verdicts and explanations in scientific and meteorological authority, but they diverge in genre and in scale. The Maldita corpus displays an adversarial register devoted to the refutation of climate denialism and to visual fact-checking, with a dense repertoire of named targets, whereas Polígrafo concentrates on a pedagogical mediation of everyday environmental practices, produced largely within an externally funded project. The functional coding also shows that the polarising public figures examined enter verification discourse predominantly as objects of verification, never as sources of authority. The mapping of these differences, which suggest different forms of organising climate-related content on these platforms, opens an avenue for future research on how the impact of verification on disinformation could vary according to the production model that sustains it.