Paleofire records represent a valuable resource for understanding long-term changes in biomass burning and fire activity, as well as their drivers. Furthermore, they offer a way to assess fire models under climatic conditions that differ from those prevalent in the contemporary era. However, further calibration studies are needed to refine the link between paleofire records and more detailed characteristics of paleofire regimes. In order to enhance our understanding of the charcoal proxy, we analysed microscopic charcoal abundance and morphology in 277 marine surface sediment samples from the eastern Atlantic Ocean off the Iberian Peninsula and the western Mediterranean Sea, and investigated their link with fire regime characteristics, climate and fuel over adjacent land in the Western Mediterranean region. Our results show that squared microscopic charcoal particles are correlated with forest fires, while elongated microscopic charcoal particles are associated with the combustion of open and mixed vegetation, so that tree vs grass burning can be inferred by the relative changes in mean microscopic charcoal elongation ratios. Microscopic charcoal concentrations are a function of fuel type, climate, fire frequency and burned areas.
Genet et al. (Mon,) studied this question.