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S-290 Intermediate Wildland Fire Behavior, Student Workbook

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S-290 Intermediate Wildland Fire Behavior, Student Workbook NFES 2891 S-290 Bookcovers.indd 2 13/11/2007 12:20:01 PM Intermediate Wildland Fire Behavior S-290 Student Workbook NOVEMBER 2007 NFES 2891 Sponsored for NWCG publication by the NWCG Training Working Team. The use of trade, firm, or corporation names in this publication is for the information and convenience of the reader and does not constitute an endorsement by the National Wildfire Coordinating Group of any product or service to the exclusion of others that may be suitable. Comments regarding the content of this publication should be directed to: National Interagency Fire Center, Fire Training, 3833 S. Development Ave., Boise, Idaho 83705. E-mail: [email protected]. Additional copies of this publication may be ordered from National Interagency Fire Center, ATTN: Great Basin Cache Supply Office, 3833 South Development Avenue, Boise, Idaho 83705. Order NFES 2891. PREFACE Intermediate Wildland Fire Behavior, S-290 is a suggested training course in the National Wildfire Coordinating Group (NWCG) wildland and prescribed fire curriculum. It was developed by an interagency group of experts with guidance from NWCG Training under authority of the NWCG. The primary participants in this development effort were: Bureau of Land Management Timothy Mathewson California Department of Forestry and Fire Protection Jim Bishop (Retired) National Weather Service Michael Baker State of Colorado, Boulder County, Cherryvale F.D. Don Whittemore USDA Forest Service Brian Finley Larry Hood U.S. Fish and Wildlife Service Rick Vollick Fire Behavior Committee Liaison Risa Lange-Navaro NWCG Fire Training Noble Dunn, Deana Parrish, Rose Secakuku The NWCG appreciates the efforts of these personnel, and all those who have contributed to the development of this training product. i ii CONTENTS PREFACE ...................................................................................................................i INSTRUCTIONAL UNITS Unit 0: Introduction ...................................................................................0.1 Unit 1: The Fire Environment ...................................................................1.1 Unit 2: Topographic Influences on Wildland Fire Behavior ....................2.1 Unit 3: Fuels ..............................................................................................3.1 Unit 4: Basic Weather Processes...............................................................4.1 Unit 5: Temperature and Humidity Relationships ....................................5.1 Unit 6: Atmospheric Stability....................................................................6.1 Unit 7: Wind Systems................................................................................7.1 Unit 8: Keeping Current with the Weather ...............................................8.1 Unit 9: Observing the Weather..................................................................9.1 Unit 10: Fuel Moisture ..............................................................................10.1 Unit 11: Extreme Wildland Fire Behavior ................................................11.1 Unit 12: Gauging Fire Behavior and Guiding Fireline Decisions ............12.1 iii iv Intermediate Wildland Fire Behavior, S-290 Unit 0 – Introduction OBJECTIVES: During this unit the cadre will: 1. Introduce instructors and students. 2. Discuss administrative concerns. 3. Explain the purpose of the course. 4. Review the course objectives. 5. Discuss course expectations. 6. Explain course evaluation methods. 7. Explain where the course fits in the wildland fire behavior curriculum. 8. Review pre-course work. 0.1 0.2 I. INTRODUCTION II. PURPOSE OF COURSE To provide the student with wildland fire behavior knowledge applicable for safe and effective wildland fire management activities (wildfires, fire use, and prescribed fire). This course introduces students to characteristics and interactions of the wildland fire environment (fuels, weather, and topography) that affect wildland fire behavior for safety purposes. Students will also be shown how such information can be applied. This course builds upon Introduction to Wildland Fire Behavior, S-190. The materials in this course, as well as in S-190, are elements of the wildland fire behavior curriculum. This may be the last formal wildland fire behavior training that students receive for the next few years. However, they will be expected to know and apply this training throughout their careers. III. COURSE OBJECTIVES • Identify and describe the characteristics of fuels, weather, and topography that influence wildland fire behavior. • Describe the interaction of fuels, weather, and topography on wildland fire behavior, fireline tactics, and safety. • Describe the causes of extreme wildland fire behavior (long-range spotting, crowning, and firewhirls) developing due to fuels, weather, and/or topography. • Interpret, apply, and document wildland fire behavior and weather information. 0.3 IV. EXPECTATIONS A. Class Expectations 1. Attendance at all sessions. 2. Be prepared to start on time. 3. Participate and share ideas. B. Student Expectations V. EVALUATIONS A. Student Evaluations Students must obtain 70% or higher on the final exam to receive a certificate of completion for this course. B. Course Evaluations This is an opportunity for students to comment on the course and instructors for the purpose of improving future courses. VI. WHERE DOES THIS COURSE FIT IN THE WILDLAND FIRE BEHAVIOR CURRICULUM? A. Introduction to Wildland Fire Behavior, S-190 Entry-level course designed around the basics of fuel, weather, and topography and how they affect wildland fire behavior in terms of safety and fire suppression actions. The course is presented to all individuals who will or could be involved with fire management activities. 0.4 B. Intermediate Wildland Fire Behavior, S-290 Builds upon the basics in S-190, but with more detailed information of fuels, weather, and topography. Provides a better basis for analyzing variables and understanding how they interact and affect wildland fire behavior for firefighter safety. In addition, the use of the Fireline Assessment Method (FLAME) provides a fireline practical tool predicting significant changes in wildland fire behavior such as rate of spread (ROS). C. Introduction to Wildland Fire Behavior Calculations, S-390 Introduces wildland fire behavior calculations by manual methods such as tables and nomograms. Gives an in depth understanding of the determinants of wildland fire behavior by discussing input to the prediction process: • Wind • Slope • Fuels • Fuel moisture Interpretations of the wildland fire behavior outputs are taught to enhance the student’s ability to understand why fire behaves as it does, and to provide “tools” to help in fire management decisions. D. Advanced Wildland Fire Behavior Calculations, S-490 Designed to give state of the art capability to determine inputs for wildland fire behavior determination and in depth knowledge of interpretations of model outputs. The course teaches students to project fire perimeter growth based on weather predictions and knowledge of fuels and topography. 0.5 E. Advanced Wildland Fire Behavior Interpretation, S-590. This is the last course of the wildland fire behavior series and the most demanding. It is designed to train future Fire Behavior Analyst (FBAN) and Long Term Fire Analyst (LTAN) used in wildland fire suppression and fire use organizations. 0.6 Intermediate Wildland Fire Behavior, S-290 Unit 1 – The Fire Environment OBJECTIVES: Upon completion of this unit, students will be able to: 1. Describe the three components of the wildland fire environment. 2. List and give examples of the three methods of heat transfer. 3. List three methods of mass transport of firebrands on wildland fire. 4. Explain the relationship between flame height/length and its relationship to the fireline intensity. 5. Describe primary environmental factors affecting ignition, fire intensity, and rate of spread of wildland fires. 6. Discuss the relationship of wildland fires of different intensities to their environments. 7. Describe the behavior of wildland fires using standard fire behavior terminology. 1.1 1.2 I. THE WILDLAND FIRE ENVIRONMENT A. Wildland Fire Behavior S-190, Introduction to Wildland Fire Behavior explained the fire triangle (heat, oxygen and fuel) and introduced the fire behavior triangle (fuels, weather and topography). Through this course you will learn how the fire behavior triangle components vary over space and time to produce changes in the behavior of wildland fire. Wildland fire behavior can be defined as the manner in which fuels ignite, flames develop, and fire spreads and exhibits other phenomena. Analysis of fire behavior recognizes the complexity of the many variable factors that influence it. Wildland fire behavior is shaped by its physical environment. Fire spread rates, fire intensity, and other characteristics of fire behavior respond to the unique and ever-changing combination of the fire environmental components. Not only does the environment affect a fire's behavior, but the fire itself can influence the environment in which it is burning. B. The Three Components of the Wildland Fire Environment • Weather • Topography • Fuels The changing states of each of the environmental components— weather, topography, and fuels—and their interactions with each other and with the fire itself, determine the characteristics and behavior of a fire at any given moment. Changes in fire behavior in space and time occur
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