Close the LOop: Attributing complex climate disaStERs to climatic and to policy changes

Climate-related extremes are intensifying in many regions due to climate change. Yet, the resulting disasters are not driven by a single factor: they emerge from the interplay of climatic and non-climatic drivers, often compounding and cascading across systems. Current methods cannot disentangle this complexity and thus cannot attribute these disasters to their multiple drivers, nor anticipate their impacts across timescales. This leaves societies unable to respond and adapt effectively. CLOSER advances the attribution and forecasting of climate events and their impacts, including slow-onset phenomena. It captures not only climatic factors, but also drivers such as land-use change, groundwater depletion, changes in exposure and social vulnerability (Fig. 1). For this, it bridges rapid advancements in climate and weather modelling, risk assessment and the socio-economics of disasters with the social sciences of adaptation and policy, from the local to the global scale. In six Case Applications across four continents, CLOSER involves in a co-creation process researchers and key stakeholders: emergency responders, climate services, adaptation planners, impacted economic sectors, intergovernmental and legal organisations. It develops a global, event-specific Knowledge Base of Climate-related Disasters, including harmonized datasets of hazard, exposure, vulnerability, impacts and attributions. Additionally, it design a Protocol for Expanded Attribution and Forecasting that targets climate-related disasters in their past, present and future manifestation, and that includes impacts, their climatic and non-climatic drivers, compound events, and cascading and systemic interactions (Fig.1). This is integrated by a forensic analysis of how policy decisions shape systemic risk and structural inequalities in the face of climate impacts, resulting in Decision-Making Frameworks for Climate Disasters that support communities, agencies and policy makers in real-life challenges.