A ‘fire regime‘ is the term given to the general pattern in which fires naturally occur in a particular ecosystem over an extended period of time. Scientists classify fire regimes using a combination of factors including frequency, intensity, size, pattern, season, and severity. Individual fires can vary greatly in severity, and the specific effects and risks caused by a fire will depend on the specifics of its fire regime. A classification system has been developed to describe the characteristics of a particular fire, determine which type of fire regime is common in a given ecosystem, and compare present fires with historical norms.
Wildfire: Trees Torching (US Fish and Wildlife Service)