<p>In the current study, we investigated period trends in climate change attitudes and polarization in these attitudes between 1986 and 2023 in the Netherlands. We expected to observe time trends towards more climate-friendly attitudes in the general public, but simultaneously, increasing polarization on the topic. We estimated trends in climate change attitudes using all accessible, nationally representative, and repeated cross-sectional surveys performed in the Netherlands to date. Using meta-analyses, we pooled the estimated time trend effects of 71 different climate change attitudes stemming from eight data sources collected between 1986 and 2023. Results confirm a positive trend towards more climate-friendly attitudes. Furthermore, against our expectations, we found a decline rather than increase of polarization. Whereas the gap in climate change attitudes between age groups increased over time, we find that it is especially the changing alignment across educational groups that explains the trend towards more climate-friendly attitudes and less polarization. Moreover, we conclude that the different components of climate change attitudes matter, as individuals have become more agreeing in their beliefs, but less so in behavior that is needed to tackle climate change. Lastly, we observed substantial heterogeneity in the 71 estimated time trend effects. We ruled out several study-level variables as possible reasons for this heterogeneity, such as the specific time period during which data were collected. It is therefore likely that the observed heterogeneity is caused by the differences in measurement of climate change attitudes. This may also explain the inconsistent results found in previous literature.</p>