Description

Knowledge of temporal changes in the area burned by wildfires is required to understand their influence on global climate change. This paper reviews the primary methods of reconstructing and measuring area burned. The area burned by wildfires is typically reconstructed using historical records, satellite imagery, tree-ring records and sediment records. These methods are described and compared in terms of the spatial and temporal resolutions and extents of the observations made using them. The different ways of measuring area burned that they employ are also described and compared. Tree-ring and sediment studies are uniquely useful over small areas and long time periods, while historical records and AVHRR images arc more useful over large areas and shorter time periods. The methods do. however, overlap over several orders of magnitude of scales of observation. The different methods of measuring area burned, the fire rotation, mean fire interval and tire cycle, are also found to have similarities. A comparison of the estimates of area burned obtained using different methods in the same area suggest that, although somewhat similar, calibration methods need to be developed to translate between them. It is thus suggested that although much current work is focussed on refining individual methods of estimation, sonic emphasis should he given to determining methods to compare the results obtained using different methods. This would allow the meaningful comparison of the estimates of area burned made over very different time periods and spatial areas.