Reconstructing regional BuRnt Areas from microcharcoal preserved In marine Sediments

Large uncertainties remain in understanding the evolution of fire activity under projected warming scenarios because fire is a complex process to integrate into global modelling. Empirical models used for projections lack potential changes in the interaction between climate, vegetation and fire. Process-based models of the coupled vegetation-fire system provide new tools to address this issue. Evaluating those models against benchmark datasets from charcoal sediment records, outside of the modern climate conditions range, is necessary. Charcoal, a fire proxy, is a carbonaceous material formed by pyrolysis during the combustion process of vegetation. Long marine charcoal records capture regional-scale biomass burning over a large range of natural climate variability, i.e. multiple warm and cold climate states. However, they describe only the response in the relative level of fire. The development of comprehensive data-model comparison studies is limited by the lack of common physical units between data and model output: relative changes in “fire” are not directly comparable to simulated carbon emissions or burnt areas. ​BRAISE intends to address the link between charcoal accumulation in marine sediments and fire regimes, i.e developing fire proxy calibration, to progress the interpretation of charcoal in a marine depositional context and, as a result, the knowledge of past regional fire regimes over long time scale.