The Party Politics of Climate Change: Introducing the PARTYCLIM Dataset to Explain Variation in Climate Change Positions and Competition Across 20 Industrialised Countries (2002-2022)

Political parties lie at the heart of climate change politics, yet the study of their behaviour has been hampered by the lack of climate-specific and comparative data. We remedy these shortcomings by building and analysing the PARTYCLIM Dataset, which positions parties on climate change across 20 industrial countries over the last two decades. The dataset is built in two stages: Firstly, through a supervised machine learning approach using a large multi-lingual language model, XLM-RoBERTa, to identify the climate change content in party manifestos. Secondly, this climate change content is hand-coded by country and climate policy experts. We code both ‘pro’ and ‘anti’ climate change content, allowing for the development of a positional measure. We also code the subcategories of climate policy included in the manifestos, and identify policy proposals and whether these are ‘hard’ or ‘soft’ climate policies. The result is the largest and richest dataset on parties’ climate change positions to date, constituting a significant contribution to the field of comparative and climate politics. The aim of this paper is therefore to present the PARTYCLIM Dataset and analyse key patterns revealed by it.