ATOC 185 Lecture 9: Tornadoes
8 Jan 2019
School
Department
Course
Professor
Document Summary
A tornado is a violently rotating column of air in the atmosphere which is in contact with the ground. Tornadoes form in association with rotating supercell thunderstorms, which often (but don"t always) form in association with a mid-latitude low pressure system. Instability - environment capable of rapidly rising motion. A trigger- to initiate rising motion in the atmosphere. Triggers: both need it some organized feature in the atmosphere which helps organize a region of rising air. Wind shear: bad for a hurricane but good for a tornado. Needed to create horizontal column of air (high-vorticity air) in the region of a supercell. Tornadoes have faster winds wind can rise fast which makes its prediction hard. Hurricanes are much larger but their spatial swath of damaging wind is much larger than for a tornado. Over 85% of world-wide tornado reports occur in north america.
