Fire-On-Fire Interactions in Three Large Wilderness Areas
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University of Montana ScholarWorks at University of Montana Graduate Student Theses, Dissertations, & Professional Papers Graduate School 2012 Fire-on-Fire Interactions in Three Large Wilderness Areas Casey Teske The University of Montana Follow this and additional works at: https://scholarworks.umt.edu/etd Let us know how access to this document benefits ou.y Recommended Citation Teske, Casey, "Fire-on-Fire Interactions in Three Large Wilderness Areas" (2012). Graduate Student Theses, Dissertations, & Professional Papers. 451. https://scholarworks.umt.edu/etd/451 This Dissertation is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. FIRE-ON-FIRE INTERACTIONS IN THREE LARGE WILDERNESS AREAS By Casey C. Teske M.S., Forest Resources, University of Idaho, Moscow, Idaho, 2002 B.S., Chemistry, University of Idaho, Moscow, Idaho, 1999 Dissertation presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Forestry The University of Montana Missoula, MT February 2012 Approved by: Sandy Ross, Associate Dean of The Graduate School Graduate School LLoyd P. Queen, Chair Department of Forest Management Carl A. Seielstad Department of Forest Management Ronald H. Wakimoto Department of Ecosystem and Conservation Sciences Anna Klene Department of Geography Colin Hardy Department of Forest Management Teske, Casey, Ph.D., Spring 2012 College of Forestry and Conservation Fire-on-Fire Interactions in Three Large Wilderness Areas Chairperson: Dr. LLoyd P. Queen Current knowledge about wildfire occurrence is not complete. Fire researchers and managers hold the assumption that previous wildfires affect subsequent wildfires; however, research regarding the interactions of large wildfires at their common boundaries is missing from the literature. This research focuses on understanding the influence of previous large wildfires on subsequent large wildfires in three wilderness areas: The Greater Bob Marshall, the Selway-Bitterroot, and the Frank Church. Data from the Monitoring Trends in Burn Severity (MTBS) project, which mapped large wildfires in the western United States occurring since 1984, are used for the research. The combination of using wilderness areas and remotely sensed images allows an objective and consistent analysis of fire-on-fire interaction that is extensive in both time and space. Standardized methods for analyzing fire interactions do not currently exist, therefore methods were developed, tested, and refined to describe, quantify, and compare once-burned and re-burned locations within a subset of ten fires in terms of size, location, timing between fires, and severity. These methods were then used to address the question of whether re-burns occur within each of the three wilderness areas. Edge and re-burn characteristics were also derived and quantified. Results were statistically and empirically compared to randomized fire intersections and to published fire history research for each area. Although a low proportion of each study area burns or re-burns, when a new fire encounters a previous fire it re-burns onto the previously burned area approximately 80% of the time. Current large wildfires are behaving in a typical fashion, although on some landscapes the amount of re-burn is not different from what would be expected due to chance. Lastly, the complexity of the post-fire landscape was assessed using texture metrics. Pre-fire and post-fire landscapes were shown to be different, with post-fire landscapes exhibiting greater diversity than pre-fire landscapes. When re-burned areas were compared to those locations that had only burned once, however, landscapes generally became less complex. Although wildfires and wildfire effects in each wilderness area differ, the overall results of this study confirm that previous fires do affect subsequent wildfires. ii Acknowledgments The time, effort and ideas of many people are included in this body of work, and to those folks I owe much gratitude and appreciation. I would specifically like to acknowledge Dr. LLoyd Queen for providing funding, mentorship, opportunities, and encouragement. I hope one day to be able pay it forward. Dr. Carl Seielstad deserves recognition for his guidance and insight in all things fire, including operations and management, and also research. Without his insight, help, and support, this project would not be what it is today. I am grateful to Dr. Colin Hardy for taking the time to work on this project with me, and for always being a good ear. Dr. Ron Wakimoto and Dr. Anna Klene deserve recognition for having an open door policy and for their support and help along the way. I would like to thank my entire family for having faith and supporting me in this project, and to Dr. Tom Bitterwolf for getting me going on the right foot. The staff at the National Center for Landscape Fire Analysis and the staff at the Numerical Terradynamic Simulation Group deserve my utmost thanks – for keeping my computers and code running; for making me laugh; and for all the fun times on wildfires. Specifically, I would like to thank Eric Rowell and Matt Jones for IDL help; Andrew Neuenschwander for PERL assistance; and, Niels Maumenee for introducing me to Subversion. The Fire Behavior guys Bret Butler and Dan Jimenez also deserve mention for getting me out the door, as do Wayne Cook, Team Hutton, and the Fire Use Community. Finally, to Fire Use, Team Awesome, Rachel Gooen, CrossFit, JT, the Belberts, and the many people whose dogs I have cared for, walked and run with, thanks for keeping me sane. I would not have gotten to this point without you all, friends and family alike. Hugs. iii Table of Contents Abstract .................................................................................................................................................................. ii Acknowledgments ............................................................................................................................................. iii List of Figures ..................................................................................................................................................... vii List of Tables ..................................................................................................................................................... viii Chapter 1 – Introduction .................................................................................................................................. 1 OVERVIEW ................................................................................................................................................. 2 RESEARCH CONTEXT ................................................................................................................................... 3 LITERATURE REVIEW .................................................................................................................................. 5 Fire Regimes ........................................................................................................................................... 5 Dataset .................................................................................................................................................. 8 Study Areas ........................................................................................................................................................ 9 Greater Bob Marshall Wilderness Area ....................................................................................................... 10 Selway-Bitterroot Wilderness Area ............................................................................................................. 12 Frank Church River of No Return Wilderness Area ...................................................................................... 14 Chapter 2 – Initial Research Stage The Influences of Space, Time, and Severity on Fire Intersections in Three Large Fire Sequences ............................................................................................................................................................. 16 OVERVIEW ............................................................................................................................................................ 17 BACKGROUND ...................................................................................................................................................... 21 Normalized Burn Ratio and Differenced NBR ................................................................................................. 21 Classified dNBR ................................................................................................................................................ 22 METHODS ............................................................................................................................................................. 23 Fire Sequences .................................................................................................................................................. 23 The Glacier Sequence ................................................................................................................................... 25