Power law distributions of wildfires across Europe: benchmarking a land surface model with observed data
B. Di Mauro1, F. Fava1, P. Frattini2, A. Camia3, R. Colombo1, and M. Migliavacca1,41Remote Sensing of Environmental Dynamics Laboratory, Earth and Environmental Sciences Department University of Milan-Bicocca, Milan, Italy 2Earth and Environmental Sciences Department University of Milan-Bicocca, Milan, Italy 3European Commission – Joint Research Centre (JRC), Institute for Environment and Sustainability, Ispra, Varese, Italy 4Biogeochemical Integration Department, Max Planck Institute for Biogeochemistry, Jena, Germany
Received: 22 Oct 2015 – Accepted for review: 13 Nov 2015 – Discussion started: 24 Nov 2015
Abstract. Monthly wildfire burned area frequency is here modeled with a power law distribution and scaling exponent across different European biomes are estimated. Data sets, spanning from 2000 to 2009, comprehend the inventory of monthly burned areas from the European Forest Fire Information System (EFFIS) and simulated monthly burned areas from a recent parameterization of a Land Surface Model (LSM), that is the Community Land Model (CLM). Power law exponents are estimated with a Maximum Likelihood Estimation (MLE) for different European biomes. The characteristic fire size (CFS), i.e. the area that most contributes to the total burned area, was also calculated both from EFFIS and CLM data set. We used the power law fitting and the CFS analysis to benchmark CLM model against the EFFIS observational wildfires data set available for Europe.
Results for the EFFIS data showed that power law fittings holds for 2–3 orders of magnitude in the Boreal and Continental ecoregions, whereas the distribution of the Alpine, Atlantic are fitted only in the upper tail. Power law instead is not a suitable model for fitting CLM simulations.
CLM benchmarking analysis showed that the model strongly overestimates burned areas and fails in reproducing size-frequency distribution of observed EFFIS wildfires. This benchmarking analysis showed that some refinements in CLM structure (in particular regarding the anthropogenic influence) are needed for predicting future wildfires scenarios, since the low spatial resolution of the model and differences in relative frequency of small and large fires can affect the reliability of the predictions.
Di Mauro, B., Fava, F., Frattini, P., Camia, A., Colombo, R., and Migliavacca, M.: Power law distributions of wildfires across Europe: benchmarking a land surface model with observed data, Nonlin. Processes Geophys. Discuss., 2, 1553-1586, doi:10.5194/npgd-2-1553-2015, 2015.