Geomorphology: A Red Hot Tool for Investigating Catastrophic Response to Wildfire

1. Geomorphology: A Red Hot Tool for Investigating Catastrophic Response to Wildfire By Mimi Diaz Department of Geological Sciences GELSS 2003 Arizona State University

2. Outline • The chasm between science and society • Rodeo-Chediski Wildfire statistics • Geologic hazards associated with wildfires • Geomorphology defined and applied • Expected outcomes of this project

3. Society Everyday people Immediate problems Science, stereotype “Different” people Abstract problems Science, reality Everyday people Everyday applications The Chasm

4. Why a Chasm? • Communication! • Between scientists • Different disciplines • Different languages • Between scientists and politicians • Politicians/broad focus/compromise • Scientists/narrow focus/logic over reality • Between scientists and general public • Theory vs application • Different scientific backgrounds

5. June—July 2002: the largest wildfire in modern Arizona history • Destroyed nearly 470 homes and burned ~500,000 acres of forest Photo courtesy Apache-Sitgreaves National Forest

6. Floods Mud Flows Debris Flows Landslides Los Alamos, NM, 2000 Banks, ID, 1997 Storm King Mtn, CO, 1994 Wildfire-Induced Geologic Hazards Photo courtesy Jim Scheidt, BLM

8. Society Perpetrators Victims Firefighters Law enforcement Politicians Science Wildlife ecologists Botanists Pedologists Hydrologists Geomorphologists? Who is involved with wildfire?

9. What is geomorphology? • The study of nature, origin, and development of landscapes through time, especially by: • Description • Classification • Prediction • Time scales: • Recent geologic time (last 10,000 years) • Human time (immediate past, present, future)

10. Wildfire effect Vegetation destruction Soil burning Rock fracturing Landscape response Reduced soil cohesion Reduced water infiltration capacity Reduced strength How do wildfires affect the landscape?

12. Rodeo-Chediski Wildfire Area, August 2002 So, what does that mean?

13. Rodeo-Chediski Wildfire Area, August 2002 burned watershed + steep slopes + rain = mass movement

14. What is Mass Movement? • Occurs when material moves downhill uniformly (as in a landslide) or chaotically (as in a debris flow) • Material includes dirt, rocks (small and large), trees, houses, vehicles, etc. • Initiates uphill, terminates in lower portions of basins

15. How can mass wasting be predicted? Observations + Applications = Forecast Topography Rock type Burn severity (soil and vegetation) Precipitation patterns Drainage basin characteristics Type of mass movement expected Location of movement Known physics and mechanics of mass movement

16. An area susceptible to debris flows: Steep topography High burn severity Drainages present

17. The Job Doesn’t End There… • Frequently, this is the point at which science stops • Results may be written up in a professional journal or as a thesis • But who tells the general public??

18. How to Cross the Chasm Translation + Circulation = Proper Communication

19. Thank You! Mimi Diaz slidehazard@hotmail.com