THE FUJITA SCALE: ITS ABUSE AND THE CURE

摘要

T. Theodore Fujita (1970) developed the Fujita scale in an attempt to categorize tornadoes by intensity and area. The scale is based upon the degree of damage caused by individual tornadoes. The scale became popular after the Super Outbreak of tornadoes which occurred April 3-4, 1974. Fujita and his staff at the University of Chicago examined tornado tracks and damage across 13 states in the Upper Midwest and rated 148 tornadoes that occurred within thirteen hours causing 600 million dollars damage. There has been use of the F-Scale as an observational tool applying the rating of a tornado by its loo ks a nd siz e rath er than the dam age it caused. This poses the question: What does the F-Scale really tell us about individual tornadoes? Does the damage path length and width tell us whether a tornado was actually worthy of the rating of F5, or F1 ? If a mile wide tornado occurs in an open field causing little damage, it may be rated F1. Similarly, we have seen thin tornadoes produce damage less than 1/4-mile that were rated F4. This paper attempts to address these issues through examination of the strengths and weaknesses of the F-Scale and how the information must be used cautiously.