Hurricanes, Tornadoes 02/14 Geos 102

tropical cyclones

large cyclonic systems w high winds and heavy rain

huge amounts of energy

redistribute heat in climate system

occur within mT air masses

necessary conditions for hurricane

vapour loaded air

latent heat energy

warm sea surface (>26C)

Coriolis (bc its a spinning system)

where do hurricanes occur

tropical seas between 8-20 degrees N/S lat

when do hurricanes occur

atlantic season: june 1 - Nov 30

few days to a week

how do hurricanes start

easterly wave over hot equatorial seas

tropical disturbance

move away from equator, begin to rotate and intensify

rain bands

formed as moist air travels into central low pressure region and rises

rapidly lifted air due to intense low pressure centre

eye

central region of descending, clear air

bounded by eye wall

eye wall

central rain band

moving wall of catastrophic winds

spiral rain bands

heavy convective showers

cumulonimbus clouds

hurricane damage

flooding

intense wind, flying debris

tornadoes

damage rating

order of increasing windspeed = lower central pressures

why hurricanes more intense w climate change

warm sea surface temperatures —> intensifies system

produces higher max wind speeds, rainfall amounts, duration

rising sea levels contribute to storm surge

tornado

violently rotating column of air that descends from storm cloud to touch down

tornado: wall cloud

cylindrical cloud protruding from base of mesocyclone

where tornado may descend

tornado: funnel

same as a tornado, but is not in contact with the ground

tornadoes originate where

in storm clouds especially where warm moist mT air lifted by colder dry cP air

tornadoes form where

thunderstorms, hurricanes, and cold fronts. Frequent in Supercell