Articles | Volume 7, issue 6
Geosci. Model Dev., 7, 2747–2767, 2014
Geosci. Model Dev., 7, 2747–2767, 2014

Development and technical paper 21 Nov 2014

Development and technical paper | 21 Nov 2014

Modelling the role of fires in the terrestrial carbon balance by incorporating SPITFIRE into the global vegetation model ORCHIDEE – Part 1: simulating historical global burned area and fire regimes

C. Yue1,2, P. Ciais1, P. Cadule1, K. Thonicke3, S. Archibald4,5, B. Poulter6, W. M. Hao7, S. Hantson8,9, F. Mouillot10, P. Friedlingstein11, F. Maignan1, and N. Viovy1 C. Yue et al.
  • 1Laboratoire des Sciences du Climat et de l'Environnement, LSCE CEA CNRS UVSQ, 91191 Gif-Sur-Yvette, France
  • 2Laboratoire de Glaciologie et Géophysique de l'Environnement, UJF, CNRS, Saint Martin d'Hères CEDEX, France
  • 3Potsdam Institute for Climate Impact Research (PIK) e.V., Telegraphenberg A31, 14473 Potsdam, Germany
  • 4CSIR Natural Resources and Environment, P.O. Box 395, Pretoria 0001, South Africa
  • 5School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, Private Bag X3,WITS, 2050, South Africa
  • 6Institute on Ecosystems and Department of Ecology, Montana State University, Bozeman, MT 59717, USA
  • 7US Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory, Missoula, MT, USA
  • 8University of Alcalá, Department of Geography, Calle Colegios 2, Alcalá de Henares 28801, Spain
  • 9Karlsruhe Institute of Technology, Institute of Meteorology and Climate research, Atmospheric Environmental Research, 82467 Garmisch-Partenkirchen, Germany
  • 10IRD, UMR CEFE, 1919 route de mende, 34293 Montpellier CEDEX 5, France
  • 11College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, EX4 4QE, UK

Abstract. Fire is an important global ecological process that influences the distribution of biomes, with consequences for carbon, water, and energy budgets. Therefore it is impossible to appropriately model the history and future of the terrestrial ecosystems and the climate system without including fire. This study incorporates the process-based prognostic fire module SPITFIRE into the global vegetation model ORCHIDEE, which was then used to simulate burned area over the 20th century. Special attention was paid to the evaluation of other fire regime indicators such as seasonality, fire size and fire length, next to burned area. For 2001–2006, the simulated global spatial extent of fire agrees well with that given by satellite-derived burned area data sets (L3JRC, GLOBCARBON, GFED3.1), and 76–92% of the global burned area is simulated as collocated between the model and observation, depending on which data set is used for comparison. The simulated global mean annual burned area is 346 Mha yr−1, which falls within the range of 287–384 Mha yr−1 as given by the three observation data sets; and is close to the 344 Mha yr−1 by the GFED3.1 data when crop fires are excluded. The simulated long-term trend and variation of burned area agree best with the observation data in regions where fire is mainly driven by climate variation, such as boreal Russia (1930–2009), along with Canada and US Alaska (1950–2009). At the global scale, the simulated decadal fire variation over the 20th century is only in moderate agreement with the historical reconstruction, possibly because of the uncertainties of past estimates, and because land-use change fires and fire suppression are not explicitly included in the model. Over the globe, the size of large fires (the 95th quantile fire size) is underestimated by the model for the regions of high fire frequency, compared with fire patch data as reconstructed from MODIS 500 m burned area data. Two case studies of fire size distribution in Canada and US Alaska, and southern Africa indicate that both number and size of large fires are underestimated, which could be related with short fire patch length and low daily fire size. Future efforts should be directed towards building consistent spatial observation data sets for key parameters of the model in order to constrain the model error at each key step of the fire modelling.

Short summary
ORCHIDEE-SPITFIRE model could moderately capture the decadal trend and variation of burned area during the 20th century, and the spatial and temporal patterns of contemporary vegetation fires. The model has a better performance in simulating fires for regions dominated by climate-driven fires, such as boreal forests. However, it has limited capability to reproduce the infrequent but important large fires in different ecosystems, where urgent model improvement is needed in the future.