The Influence of Vegetation, Fire Spread and Fire Behaviour on Biomass Burning and Trace Gas Emissions: Results from a Process-Based Model

A process-based fire regime model (SPITFIRE) has been developed, coupled with ecosystem dynamics in the LPJ Dynamic Global Vegetation Model, and used to explore spatial and temporal patterns of fire regimes and the current impact of fire on the ter- 5 restrial carbon cycle and associated emissions of trace atmospheric constituents. The model estimates an average release of 2.24 PgCyr-1 as CO2 from biomass burning during the 1980s and 1990s. Comparison with observed active fire counts shows that the model reproduces where fire occurs and can mimic broad geographic patterns in the peak fire season, although the predicted peak is 1¿2 months late in some regions. 10 Modelled fire season length is generally overestimated by about one month, but shows a realistic pattern of differences among biomes. Comparisons with remotely sensed burnt-area products indicate that the model reproduces broad geographic patterns of annual fractional burnt area over most regions, including the boreal forest, although interannual variability in the boreal zone is underestimated. Overall SPITFIRE produces 15 realistic simulations of spatial and temporal patterns of fire under modern conditions and of the current impact of fire on the terrestrial carbon cycle and associated emissions of trace greenhouse gases and aerosols.JRC.H.5-Land Resources Managemen