A time-integrated MODIS burn severity assessment using the multi-temporal differenced normalized burn ratio (dNBRMT) |
| |
| Authors: | S Veraverbeke S Lhermitte WW Verstraeten R Goossens |
| |
| Institution: | 1. Department of Geography, Ghent University, Krijgslaan 281 S8, BE-9000 Ghent, Belgium;2. Centro de Estudios Avanzados en Zonas Aridas, Universidad de la Serena, Campus A. Bello, ULS, Chile;3. Department of Biosystems, Katholieke Universiteit Leuven, Willem de Croylaan 34, BE-3001, Belgium |
| |
| Abstract: | Burn severity is an important parameter in post-fire management. It incorporates both the direct fire impact (vegetation depletion) and ecosystem responses (vegetation regeneration). From a remote sensing perspective, burn severity is traditionally estimated using Landsat's differenced normalized burn ratio (dNBR). In this case study of the large 2007 Peloponnese (Greece) wildfires, Landsat dNBR estimates correlated reasonably well with Geo composite burn index (GeoCBI) field data of severity (R2 = 0.56). The usage of Landsat imagery is, however, restricted by cloud cover and image-to-image normalization constraints. Therefore a multi-temporal burn severity approach based on coarse spatial, high temporal resolution moderate resolution imaging spectroradiometer (MODIS) imagery is presented in this study. The multi-temporal dNBR (dNBRMT) is defined as the 1-year integrated difference between burned pixels and their unique control pixels. These control pixels were selected based on time series similarity and spatial context and reflect how burned pixels would have behaved in the case no fire had occurred. Linear regression between downsampled Landsat dNBR and dNBRMT estimates resulted in a moderate-high coefficient of determination R2 = 0.54. dNBRMT estimates are indicative for the change in vegetation productivity due to the fire. This change is considerably higher for forests than for more sparsely vegetated areas like shrub lands. Although Landsat dNBR is superior for spatial detail, MODIS-derived dNBRMT estimates present a valuable alternative for burn severity mapping at continental to global scale without image availability constraints. This is beneficial to compare trends in burn severity across regions and time. Moreover, thanks to MODIS's repeated temporal sampling, the dNBRMT accounts for both first- and second-order fire effects. |
| |
| Keywords: | Differenced normalized burn ratio Fire severity Burn severity MODIS Landsat Thematic Mapper Composite burn index Multi-temporal Vegetation regeneration |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
