Climate and Vegetation as Driving Factors in Global Fire Activity

Global active fire distributions have been determined for a 12 month period from daily acquired, low spatial resolution satellite imagery. These distributions have been grouped into a small number of classes based on the spatial and temporal characteristics of the data. A global climatology of monthly temperature and precipitation data was used to derive warmth and moisture indices. We show how different patterns of fire activity, as represented by the fire classes, can be related to particular climate conditions. Vegetation type is also shown to be important in determining fire activity, particularly in tropical regions. Our results support the premise that fire regimes will change under changed climate conditions and that the empirical approach to the investigation of the fire-climate relationship could provide a complementary tool to the physically-based climate change prediction models.