Hazards - Tropical Storms Flashcards
tropical storm
- deep area of low pressure formed in tropics
- winds move in spiral around calm centre, eye
- powerful winds & heavy rainfall
where do tropical storms form
- warm oceans above 27ºC - summer & autumn temps r highest
- 5º-15º n/s of equator
- not at equator - not enough coriolis
formation of hurricane
step 1
- air is heated above surface of warm tropical oceans
- warm air rises rapidly bc low-pressure conditions
formation of hurricane
step 2
rising air draws up more air & large volumes of moisture from ocean = strong winds
formation of storm
step 3
coriolis effect make air spin around the eye
formation of storm
step 4
- air rises -> cools & condenses -> large cumulonimbus clous -> generates torrential rainfall
- gives off heat when air cools = power for storm
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formation of storm
step 5
cold air sinks in eye = no cloud + dry + calm
formation of storm
step 6
storm travels across ocean in prevailing winds
formation of storm
step 7
- meets land
- no more moisture & heat to fuel it from ocean = loss in power
the eye
- centre
- diametre - usually between 20km-50km
- calm & clear
- on all sides there is a towering bank of cloud, eye wall = strongest winds & rain
primary effects of storms
strong winds
widespread damage to buildings, infrastructure, trees & crops
primary effects of storms
storm surges
- low air pressure = high sea levels
- strong on-shore winds = big waves which move to coasts = lots of coast flooding
primary effects of storms
heavy rainfall
torrential rain = widespread floods
secondary effects of storms
mudslides & landslides
unstable slopes saturate with rain & floodwater
secondary effects of storms
polluted water supplies
more deaths bc diseases such as cholera
