The Fire Modeling Intercomparison Project (FireMIP) for CMIP7

Abstract. Fire is a global phenomenon and a key Earth system process. Extreme fire events have increased in recent years, and fire frequency and intensity are projected to rise across most regions and biomes, posing substantial challenges for ecosystems, the carbon cycle, and society. The Fire Model Intercomparison Project (FireMIP), launched in 2014, has contributed to advancing global fire modeling in Dynamic Global Vegetation Models (DGVMs) and improving understanding of fire's local drivers and local impacts on vegetation and land carbon budgets through land offline (i.e., uncoupled from the atmosphere) simulations. We now bring FireMIP into Coupled Model Intercomparison Project Phase 7 (CMIP7) to: (1) evaluate fire simulations in state-of-the-art fully coupled Earth system models (ESMs); (2) assess fire regime changes in the past, present, and future, and identify their primary natural and anthropogenic forcings and causal pathways within the Earth system, including the associated uncertainties; and (3) quantify the impacts of fires and fire changes on climate, ecosystems, and society across Earth system components, regions, and timescales, and elucidate the underlying mechanisms. FireMIP in CMIP7 will advance the fire and fire-related modeling in fully coupled ESMs, and provide a quantitative, detailed, and process-based understanding of fire's role in the Earth system by using models that incorporate critical climate feedbacks and multi-model, multi-initial-condition, and CMIP7 multi-scenario ensembles. This paper presents the motivation, scientific questions, experimental design and its rationale, model inputs and outputs, and the analysis framework for FireMIP in CMIP7, providing guidance for Earth system modeling teams conducting simulations and informing communities studying fire, climate change, and climate solutions.