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Background As fire seasons in the Western US intensify and lengthen, fire managers have been grappling with increases in simultaneous, significant incidents that compete for response resources and strain capacity of the current system. Aims To address this challenge, we explore a key research question: what precursors are associated with ignitions that evolve into incidents requiring high levels of response personnel? Methods We develop statistical models linking human, fire weather and fuels related factors with cumulative and peak personnel deployed. Key results Our analysis generates statistically significant models for personnel deployment based on precursors observable at the time and place of ignition. Conclusions We find that significant precursors for fire suppression resource deployment are location, fire weather, canopy cover, Wildland–Urban Interface category, and history of past fire. These results align partially with, but are distinct from, results of earlier research modelling expenditures related to suppression which include precursors such as total burned area which become observable only after an incident. Implications Understanding factors associated with both the natural system and the human system of decision-making that accompany high deployment fires supports holistic risk management given increasing simultaneity of ignitions and competition for resources for both fuel treatment and wildfire response.
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Future regional increases in simultaneous large Western USA wildfires
BackgroundWildfire simultaneity affects the availability and distribution of resources for fire management: multiple small fires require more resources to fight than one large fire does. AimsThe aim of this study was to project the effects of climate change on simultaneous large wildfires in the Western USA, regionalised by administrative divisions used for wildfire management. MethodsWe modelled historical wildfire simultaneity as a function of selected fire indexes using generalised linear models trained on observed climate and fire data from 1984 to 2016. We then applied these models to regional climate model simulations of the 21st century from the NA-CORDEX data archive. Key resultsThe results project increases in the number of simultaneous 1000+ acre (4+ km2) fires in every part of the Western USA at multiple return periods. These increases are more pronounced at higher levels of simultaneity, especially in the Northern Rockies region, which shows dramatic increases in the recurrence of high return levels. ConclusionsIn all regions, the models project a longer season of high simultaneity, with a slightly earlier start and notably later end. These changes would negatively impact the effectiveness of fire response. ImplicationsBecause firefighting decisions about resource distribution, pre-positioning, and suppression strategies consider simultaneity as a factor, these results underscore the importance of potential changes in simultaneity for fire management decision-making.
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- PAR ID:
- 10644144
- Publisher / Repository:
- DOI PREFIX: 10.1071
- Date Published:
- Journal Name:
- International Journal of Wildland Fire
- Volume:
- 32
- Issue:
- 9
- ISSN:
- 1049-8001
- Format(s):
- Medium: X Size: p. 1304-1314
- Size(s):
- p. 1304-1314
- Sponsoring Org:
- National Science Foundation
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