Addressing climate change's existential threat demands a global effort to rapidly reduce carbon emissions. However, political gridlock fuelled by societal polarisation can stymie effective action. POLARCLIMATE confronts this challenge, studying interventions to curb climate scepticism and foster consensus. POLARCLIMATE will use a social media lens to advance the current state-of-the-art on climate polarisation, tackling three key research challenges. First, existing studies of climate polarisation fail to consider how passive engagement with climate narratives shape climate opinions. Second, studies of climate polarisation are typically siloed to a single platform, limiting their demographic relevance and preventing a robust cross-platform analysis of content and structure. Finally, studies do not adequately consider the agents who drive climate polarisation, especially those organisations with a vested financial interest in maintaining the status quo. To address these challenges, POLARCLIMATE will take an interdisciplinary, multi-modal approach drawing on quantitative methods from networks and data science, and qualitative methods from climate communications. The analysis of passive consumption and cross-platform structure will be studied using Bayesian inference and network reconstruction methods, and content will be analysed using taxonomies of climate scepticism and computer-aided topic modelling across various climate publics. Finally, organisational financial interests will be identified by using Bloomberg financial data, and compared to the rhetoric of corresponding organisations on social media. POLARCLIMATE will balance scientific rigour with policy relevance. The project's outputs will offer multi-modal evidence to inform the development of concrete policy recommendations aimed at mitigating the adverse impacts of climate polarization. These recommendations aim to contribute to a more unified and effective global response to climate change.