EARTHSC 2GG3 Lecture Notes - Tropical Cyclone
Document Summary
Tropical cyclone: storm system of low-pressure surrounded by strong rotating winds (more than 200km/h), with torrential rains, thunderstorms, tornadoes, high surge of seawater. Hurricanes: a tropical cyclone with 1 min average winds at 10m altitude in excess of 32m/s occurring over the north atlantic or eastern north pacific, north atlantic and eastern pacific. Cyclones: south asia (india, bangladesh, sri lanka. Begin to develop over warm seawater, between 5 and 20 degrees latitude. Rising air and condensation can build up into convective chimney" of thunderstorms: convection may strengthen when air rises to high elevations, warm air rises, expands and cools, releases latent heat of condensation. Center of storm is low-pressure zone called eye. Winds rotate counterclockwise in northern hemisphere and clockwise in the southern hemisphere. Highest wind speeds exist along the edge of the eye wall. Saffir-simpson hurricane scale is based on barometric pressure and average wind speed. Lower-category storms can do almost as much damage as higher-category storms.