Giving Ecological Meaning to Satellite-Derived Fire Severity Metrics across North American Forests

Remote Sensing

Ellen Whitman¹  JenniferL. Barnes²  LisaM. Holsinger³  SeanA. Parks³  LisaB. Saperstein⁴  AnthonyC. Caprio⁵  RebeccaJ. Smith⁶  Luke Collins⁷  Jonathan Boucher⁸  MichaelJ. Koontz⁹  Jean-François Bourdon^1,10  Marc-André Parisien^1,11  RachelA. Loehman^1,11  Jane Park^1,11  Adam Collingwood^1,12  Yan Boucher^1,13  Charlotte Smetanka^1,14  RonJ. Hall^1,15  Nick Soverel^1,16 

[1] Evolution, La Trobe University, Bundoora, VIC 3086, Australia;Alaska Science Center, US Geological Survey, 4210 University Drive, Anchorage, AK 99508, USA;Aldo Leopold Wilderness Research Institute, Rocky Mountain Research Station, US Forest Service, 790 E. Beckwith Ave, Missoula, MT 59801, USA;Banff Field Unit, Banff National Park, Parks Canada, PO Box 900, Banff, AB T1L 1K2, Canada;Centre for Forest Research, Université du Québec à Montréal, P.O. Box 8888, Centre-ville Station, Montréal, QC H3C 3P8, Canada;Department of Applied Geomatics, Université de Sherbrooke, 2500 Boulevard de l’Université, Sherbrooke, QC J1K 0A5, Canada;;Department of Ecology, Environment &Département des Sciences du bois et de la Forêt, Faculté de Foresterie, de Géographie et de Géomatique, Université Laval, 2405, rue de la Terrasse, Quebec City, QC G1V 0A6, Canada;Earth Lab, University of Colorado, Boulder, CO 80303, USA;National Park Service, Alaska Regional Office, 4175 Geist Rd., Fairbanks, AK 99709, USA;Natural Resources Canada, Canadian Forest Service, Northern Forestry Centre, 5320–122 Street, Edmonton, AB T6H 3S5, Canada;Sequoia and Kings Canyon National Parks, National Park Service, Three Rivers, CA 93271, USA;Société de Protection des Forêts Contre le feu, 715 7e rue de l’Aéroport, Quebec City, QC G2G 2S7, Canada;US Fish and Wildlife Service, 1011 E. Tudor Rd., Anchorage, AK 99503, USA;Waterton Lakes National Park, Parks Canada, 1 Compound Rd., Waterton Park, AB T0K 2M0, Canada;Yellowstone National Park, National Park Service, 106 Stable St, Yellowstone National Park, WY 82190, USA;

关键词: burn severity;    CBI;    composite burn index;    fire effects;    fire severity;    Google Earth Engine;    Random Forest;   

DOI  :  10.3390/rs11141735

来源: DOAJ

【 摘 要 】

Satellite-derived spectral indices such as the relativized burn ratio (RBR) allow fire severity maps to be produced in a relatively straightforward manner across multiple fires and broad spatial extents. These indices often have strong relationships with field-based measurements of fire severity, thereby justifying their widespread use in management and science. However, satellite-derived spectral indices have been criticized because their non-standardized units render them difficult to interpret relative to on-the-ground fire effects. In this study, we built a Random Forest model describing a field-based measure of fire severity, the composite burn index (CBI), as a function of multiple spectral indices, a variable representing spatial variability in climate, and latitude. CBI data primarily representing forested vegetation from 263 fires (8075 plots) across the United States and Canada were used to build the model. Overall, the model performed well, with a cross-validated R² of 0.72, though there was spatial variability in model performance. The model we produced allows for the direct mapping of CBI, which is more interpretable compared to spectral indices. Moreover, because the model and all spectral explanatory variables were produced in Google Earth Engine, predicting and mapping of CBI can realistically be undertaken on hundreds to thousands of fires. We provide all necessary code to execute the model and produce maps of CBI in Earth Engine. This study and its products will be extremely useful to managers and scientists in North America who wish to map fire effects over large landscapes or regions.

【 授权许可】

Unknown