Current Research

My current research focuses on the develop of new understanding into the fundamental physics governing wildland fire ignition, spread and intensity, along with improved methods for quantifying wildland fire intensity using in-situ instrumentation.

Research Interests

My primary research interests include the development of tools for simulating wind flow at fine resolution, fire induced tree mortality, and improvement of existing firefighter safety zone guidelines.

Past Research

Wildland fire is a complex process that involves biology, chemistry, fluid dynamics and energy transfer. It is an everpresent phenomena in many natural ecosystems. Advances in our understanding of the fundamental physics governing fire facilitate improved methods and tools for managing fire safely and effectively.

Why This Research is Important

I developed the current Firefighter safety zone standards. I was the lead scientist on the development of the WindWizard and WindNinja wind modeling systems. I was the lead scientist for the development of the FireStem tree mortality simulation model.

Education

• Brigham Young University, B.S. Mechanical Engineering 1986
• Brigham Young University, M.S. Mechanical Engineering 1988
• Brigham Young University, Ph.D. Mechanical Engineering with an emphasis on energy transport in particle-laden flames. 1992

Featured Publications & Products

• Butler, B. W. 2014. Wildland firefighter safety zones: A review of past science and summary of future needs.
• Frankman, David; Webb, Brent W.; Butler, Bret W.; Jimenez, Daniel; Forthofer, Jason M.; Sopko, Paul; Shannon, Kyle S.; Hiers, J. Kevin; Ottmar, Roger D. 2012. Measurements of convective and radiative heating in wildland fires.
• Butler, Bret W.; Dickinson, Matthew B. 2010. Tree injury and mortality in fires: developing process-based models.
• Butler, B. W.; Wagenbrenner, N. S.; Forthofer, J. M.; Lamb, B. K.; Shannon, K. S.; Finn, D.; Eckman, R. M.; Clawson, K.; Bradshaw, L.; Sopko, P.; Beard, S.; Jimenez, D.; Wold, C.; Vosburgh, M. 2015. High-resolution observations of the near-surface wind field over an isolated mountain and in a steep river canyon.
• Butler, B.W.; Ottmar, R.D.; Rupp, T.S.; Jandt, R.; Miller, E.; Howard, K.; Schmoll, R.; Theisen, S.; Vihnanek, R.E.; Jimenez, D. 2013. Quantifying the effect of fuel reduction treatments on fire behavior in boreal forests.
• Butler, Bret W.; Bartlette, Roberta A.; Bradshaw, Larry S.; Cohen, Jack D.; Andrews, Patricia L.; Putnam, Ted; Mangan, Richard J. 1998. Fire behavior associated with the 1994 South Canyon fire on Storm King Mountain, Colorado.
• Butler, Bret W.; Finney, Mark; Bradshaw, Larry; Forthofer, Jason; McHugh, Chuck; Stratton, Rick; Jimenez, Dan. 2006. WindWizard: A New Tool for Fire Management Decision Support.
• Frankman, David; Webb, Brent W.; Butler, Bret W.; Latham, Don J. 2010. Fine fuel heating by radiant flux.
• Pickett, Brent M.; Isackson, Carl; Wunder, Rebecca; Fletcher, Thomas H.; Butler, Bret W.; Weise, David R. 2009. Flame interactions and burning characteristics of two live leaf samples.
• Butler, Bret W.; Cook, Wayne. 2007. The fire environment--innovations, management, and policy; conference proceedings.

Publications

• Page, Wesley G.; Wagenbrenner, Natalie S.; Butler, Bret W.; Blunck, David L. 2019. An analysis of spotting distances during the 2017 fire season in the Northern Rockies, USA.
• Dickinson, Matthew B.; Butler, Bret W.; Hudak, Andrew T.; Bright, Benjamin C.; Kremens, Robert L.; Klauberg, Carine . 2019. Inferring energy incident on sensors in low-intensity surface fires from remotely sensed radiation and using it to predict tree stem injury.
• Clements, Craig B.; Kochanski, Adam K.; Seto, Daisuke ; Davis, Braniff ; Camacho, Christopher ; Lareau, Neil P.; Contezac, Jonathan ; Restaino, Joseph ; Heilman, Warren E.; Krueger, Steven K.; Butler, Bret ; Ottmar, Roger D.; Vihnanek, Robert ; Flynn, James ; Filippi, Jean-Baptiste ; Barboni, Toussaint ; Hall, Dianne E.; Mandel, Jan ; Jenkins, Mary Ann; O'Brien, Joseph ; Hornsby, Ben ; Teske, Casey . 2019. The FireFlux II experiment: a model-guided field experiment to improve understanding of fire atmosphere interactions and fire spread.
• Weise, David R.; Fletcher, Thomas H.; Johnson, Timothy J.; Hao, WeiMin ; Dietenberger, Mark ; Princevac, Marko ; Butler, Bret ; McAllister, Sara ; O’Brien, Joseph ; Loudermilk, Louise ; Ottmar, Roger ; Hudak, Andrew ; Kato, Akira ; Shotorban, Babak ; Mahalingam, Shankar ; Mell, William E. 2018. A project to measure and model pyrolysis to improve prediction of prescribed fire behavior Chapter 3.
• Page, Wesley G.; Wagenbrenner, Natalie S.; Butler, Bret W.; Forthofer, Jason M.; Gibson, Chris . 2018. An evaluation of NDFD weather forecasts for wildland fire behavior prediction.
• Page, Wesley G.; Butler, Bret W. 2018. Fuel and topographic influences on wildland firefighter burnover fatalities in Southern California.
• Wagenbrenner, Natalie S.; Forthofer, Jason M.; Gibson, Chris ; Indreland, Abby ; Lamb, Brian K.; Butler, Bret W. 2018. Observations and predictability of gap winds in the Salmon River Canyon of Central Idaho, USA.
• Campbell, Michael J.; Dennison, Philip E.; Hudak, Andrew T.; Parham, Lucy M.; Butler, Bret W. 2018. Quantifying understory vegetation density using small-footprint airborne lidar.
• Hudak, Andrew T.; Freeborn, Patrick H.; Lewis, Sarah A.; Hood, Sharon M.; Smith, Helen Y.; Hardy, Colin C.; Kremens, Robert J.; Butler, Bret W.; Teske, Casey; Tissell, Robert G.; Queen, Lloyd P.; Nordgren, Bryce L.; Bright, Benjamin C.; Morgan, Penelope; Riggan, Philip J.; Macholz, Lee; Lentile, Leigh B.; Riddering, James P.; Mathews, Edward E. 2018. The Cooney Ridge Fire Experiment: An early operation to relate pre-, active, and post-fire field and remotely sensed measurements.
• Campbell, Michael J.; Dennison, Philip E.; Butler, Bret W. 2017. A LiDAR-based analysis of the effects of slope, vegetation density, and ground surface roughness on travel rates for wildland firefighter escape route mapping.
• Page, Wesley G.; Butler, Bret W. 2017. An empirically based approach to defining wildland firefighter safety and survival zone separation distances.
• Adams, Theodore Ted; Butler, Bret W.; Brown, Sara; Wright, Vita; Black, Anne. 2017. Bridging the divide between fire safety research and fighting fire safely: How do we convey research innovation to contribute more effectively to wildland firefighter safety.
• Sikkink, Pamela G.; Jain, Theresa B.; Reardon, James; Heinsch, Faith Ann; Keane, Robert E.; Butler, Bret; Baggett, L. Scott. 2017. Effect of particle aging on chemical characteristics, smoldering, and fire behavior in mixed-conifer masticated fuel.
• Finn, D.; Reese, B.; Butler, B.; Wagenbrenner, N.; Clawson, K. L.; Rich, J.; Russell, E.; Gao, Z.; Liu, H. 2016. Evidence for gap flows in the Birch Creek Valley, Idaho.
• Clements, Craig B.; Lareau, Neil P.; Seto, Daisuke; Contezac, Jonathan; Davis, Braniff; Teske, Casey; Zajkowski, Thomas J.; Hudak, Andrew T.; Bright, Benjamin C.; Dickinson, Matthew B.; Butler, Bret W.; Jimenez, Daniel; Hiers, J. Kevin. 2016. Fire weather conditions and fire-atmosphere interactions observed during low-intensity prescribed fires - RxCADRE 2012.
• Ottmar, Roger D.; Hiers, J. Kevin; Butler, Bret W.; Clements, Craig B.; Dickinson, Matthew B.; Hudak, Andrew T.; O'Brien, Joseph; Potter, Brian E.; Rowell, Eric M.; Strand, Tara M.; Zajkowski, Thomas J. 2016. Measurements, datasets and preliminary results from the RxCADRE project-2008, 2011 and 2012.
• Butler, Bret; Teske, C.; Jimenez, Dan; O'Brien, Joseph; Sopko, Paul; Wold, Cyle; Vosburgh, Mark; Hornsby, Ben; Loudermilk, E. Louise. 2016. Observations of energy transport and rate of spreads from low-intensity fires in longleaf pine habitat-RxCADRE 2012.
• Campbell, Michael J.; Dennison, Philip E.; Butler, Bret W. 2016. Safe separation distance score: A new metric for evaluating wildland firefighter safety zones using lidar.
• Mueller, Eric; Skowronski, Nicholas; Clark, Kenneth; Kremens, Robert; Gallagher, Michael; Thomas, Jan; El Houssami, Mohamad; Filkod, Alexander; Butler, Bret; Hom, John; Mell, William; Simeoni, Albert. 2015. Initial results from a field experiment to support the assessment of fuel treatment effectiveness in reducing wildfire intensity and spread rate.
• Butler, Bret; Parsons, Russ; Mell, William. 2015. Recent findings relating to firefighter safety zones.
• Butler, B. W.; Webb, J.; Hogge, J.; Wallace, T. 2015. Vegetation clearance distances to prevent wildland fire caused damage to telecommunication and power transmission infrastructure.
• Butler, B. W.; Wallace, T.; Hogge, J. 2015. Vegetation clearance distances to prevent wildland fire caused damage to telecommunication and power transmission infrastructure (2).
• Forthofer, Jason M.; Butler, Bret W.; McHugh, Charles W.; Finney, Mark A.; Bradshaw, Larry S.; Stratton, Richard D.; Shannon, Kyle S.; Wagenbrenner, Natalie S. 2014. A comparison of three approaches for simulating fine-scale surface winds in support of wildland fire management. Part II. An exploratory study of the effect of simulated winds on fire growth simulations.
• Forthofer, Jason M.; Butler, Bret W.; Wagenbrenner, Natalie S. 2014. A comparison of three approaches for simulating fine-scale surface winds in support of wildland fire management: Part I. Model formulation and comparison against measurements.
• Mueller, Eric; Skowronski, Nicholas; Simeoni, Albert; Clark, Kenneth; Kremens, Robert; Mell, William; Gallagher, Michael; Thomas, Jan; Filkov, Alexander; Houssami, Mohamad El; Hom, John; Butler, Bret. 2014. Fuel treatment effectiveness in reducing fire intensity and spread rate - An experimental overview.
• Jolly, W. Matt; Parsons, Russell; Varner, J. Morgan; Butler, Bret W.; Ryan, Kevin C.; Gucker, Corey L. 2012. Do mountain pine beetle outbreaks change the probability of active crown fire in lodgepole pine forests.
• Nelson, Ralph M., Jr..; Butler, Bret W.; Weise, David R. 2012. Entrainment regimes and flame characteristics of wildland fires.
• Frankman, David; Webb, Brent W.; Butler, Bret W.; Jimenez, Daniel; Harrington, Michael. 2012. The effect of sampling rate on interpretation of the temporal characteristics of radiative and convective heating in wildland flames.
• Cruz, Miguel G.; Butler, Bret W.; Viegas, Domingos X.; Palheiro, Pedro. 2011. Characterization of flame radiosity in shrubland fires.
• Butler, Bret; Jimenez, D.; Forthofer, J.; Shannon, K.; Sopko, Paul. 2010. A portable system for characterizing wildland fire behavior.
• Butler, Bret. 2010. Characterization of convective heating in full scale wildland fires.
• Butler, Bret; Forthofer, Jason. 2010. Firefighter Safety Zone: The effect of terrain slope of separation distance.
• Butler, Bret; Jimenez, D.; Forthofer, J.; Sopko, Paul; Shannon, K.; Reardon, Jim. 2010. In-situ characterization of wildland fire behavior.
• Forthofer, J.; Shannon, K.; Butler, Bret. 2010. Initialization of high resolution surface wind simulations using NWS gridded data.
• Forthofer, J.; Butler, Bret. 2010. Large scale fire whirls: Can their formation be predicted.
• Butler, Bret; Forthofer, J.; Shannon, K.; Jimenez, D.; Frankman, D. 2010. The effect of terrain slope on firefighter safety zone effectiveness.
• Butler, Bret. 2009. Efforts to update firefighter safety zone guidelines.
• Jimenez, D.; Butler, B.; Hiers, K.; Ottmar, R.; Dickinson, M.; Kremens, R.; O'Brien, J.; Hudak, A.; Clements, C. 2009. Rx-CADRE (Prescribed Fire Combustion-Atmospheric Dynamics Research Experiments) collaborative research in the core fire sciences.
• Frankman, D.; Webb, B. W.; Butler, B. W. 2008. Influence of absorption by environmental water vapor on radiation transfer in wildland fires.
• Forthofer, Jason; Butler, Bret. 2007. Differences in simulated fire spread over Askervein Hill using two advanced wind models and a traditional uniform wind field.
• Jimenez, Dan; Forthofer, Jason; Reardon, James; Butler, Bret. 2007. Fire behavior sensor package remote trigger design.
• Frankman, David; Webb, Brent W.; Butler, Bret W. 2007. Influence of radiation absorption by environmental water vapor on radiation transfer in wildland fires.
• Cook, Wayne; Butler, Bret W. 2007. Introduction-2nd Fire Behavior and Fuels Conference: The fire environment-innovations, management, and policy.
• Andrews, Patricia L.; Butler, Bret W. 2006. Fuels Management-How to Measure Success: Conference Proceedings.
• Weise, David R.; Fletcher, Thomas; Baxter, Larry; Mahalingam, Shankar; Zhou, Xiangyang; Pagni, Patrick; Linn, Rod; Butler, Bret. 2004. A fundamental look at fire spread in California chaparral.
• Jimenez, D. M.; Butler, B. W.; Reardon, J. 2003. Stem mortality in surface fires: Part II, experimental methods for characterizing the thermal response of tree stems to heating by fires.
• Cohen, Jack D.; Butler, Bret W. 1998. Modeling potential structure ignitions from flame radiation exposure with implications for wildland/urban interface fire management.
• Butler, Bret W.; Reynolds, Timothy D. 1997. Wildfire case study: Butte City Fire, southeastern Idaho, July 1, 1994.

Research Highlights

Highlight	Title	Year
RMRS-2014-120	Forest Service Researchers Focus on Firefighter Safety Wildland firefighters continue to be injured or killed in fire entrapments. Past entrapment data indicates that policy changes, work practices, ...	2014
RMRS-2018-84	Improving firefighter escape route mapping through LiDAR-based analysis Wildland fires place firefighters in a dangerous working environment and their safety relies on knowing the safest pathways to a safety zone bef ...	2018