Wildland fire hazard and risk: problems, definitions, and context
Document Type: Journal Article
Author(s): Colin C. Hardy
Publication Year: 2005

Cataloging Information

  • aesthetics
  • catastrophic fires
  • disturbance
  • ecosystem dynamics
  • education
  • fire case histories
  • fire danger rating
  • fire intensity
  • fire management
  • fire regime
  • fire regimes
  • fire severity
  • fire terminology
  • multiple resource management
  • Oregon
  • public information
  • risk assessment
  • southern California
  • wildfires
Record Maintained By:
Record Last Modified: August 13, 2020
FRAMES Record Number: 43123
Tall Timbers Record Number: 18294
TTRS Location Status: In-file
TTRS Call Number: Fire File
TTRS Abstract Status: Fair use, Okay, Reproduced by permission

This bibliographic record was either created or modified by the Tall Timbers Research Station and Land Conservancy and is provided without charge to promote research and education in Fire Ecology. The E.V. Komarek Fire Ecology Database is the intellectual property of the Tall Timbers Research Station and Land Conservancy.


The risks, hazards, and relative severity of wildland fires are presented here within the ecological context of historical natural fire regimes, time, space, and process. As the public dialogue on the role and impacts of wildland fire increases, it is imperative for all partners to converge on clear and concise terminology that defines risk, hazard, and the characteristic (or uncharacteristic) nature of wildland fire. These terms must be defined in the context of scale-both spatial and temporal. The concept of historical natural fire regimes involves a classification of the characteristic, or 'natural' processes and effects associated with wildland fire occurring in sustainable ecosystems. When a wildland fire occurs within the time, space, and severity parameters of the historical natural fire regime, the fire can be called natural, or 'characteristic'. The milieu of disturbance effects we call catastrophic, such as economic losses, damages to communities and structures, or impacts on short-term aesthetic values involve social, cultural, and economic values and risks-none is directly associated with ecological values, damages, or risks. In the context of technical risk assessments, the term 'risk' considers not only the probability of an event, but also includes values and expected losses. However, within the fire community it refers only to the probability of ignition (both man- and lightning-caused). 'Hazard' refers to the state of the fuel, exclusive of weather or the environs in which the fuel is found. Unlike many common uses of the term 'severity', fire severity refers specifically to the effect a fire has on wildland systems. It is inappropriate to use the term severity to describe the behavior of the fire phenomenon itself. Instead, we should confine its use to that relating only to a fire's effect. Finally, I discuss the limitations and conflicts to integrating all social, cultural, economic, health, and safety values in our public and policy-forming dialogue relating to fire risk, hazard, and severity. Typical risk assessments consider all relevant endpoints, including socio-economic, management, as well as ecological elements. Herein, I use the Black Mountain 2 Fire from August 2003 in the northern Rockies to illustrate the spatiotemporal extent of fire's impacts on the endpoints. When expressed over all affected spatiotemporal scales, the overlay of all endpoints from this synthetic scenario results in a 'decision space' ranging in time from an hour to a century, and in space ranging from a few square meters to the continent.

Online Link(s):
Hardy, C. C. 2005. Wildland fire hazard and risk: problems, definitions, and context. Forest Ecology and Management, v. 211, no. 1-2, p. 73-82. 10.1016/j.foreco.2005.01.029.