Impacts of tropical cyclones

How is the intertropical convergence zone linked to the formation of tropical cyclones in the North and South Hemisphere?

The ITCZ is the thermal equator, a band of low pressure and high temperature. This leads to more moisture and humidity along with rising air forming cumulonimbus thunderstorm clouds leading to formation of tropical cyclones.

What are primary impacts?

Direct causes in very short term, immediate.

What are secondary impacts?

Knock on effects in the hours, days and weeks following the hazard.

5 hazards of tropical cyclones

• Coastal flooding

• Storm surge

• Landslide

• High winds

• Intense rainfall

Coastal Flooding

• Combination of intense rain + storm surge puts coastal areas at risks of flooding

• Tourism on coast damaged - loss of jobs

• Damages property - much costs

• Farming contaminated by saltwater

  • Flooding by salt water kills plant species because they drown.

High Winds

• Winds of 119-250km/h

• Infrastructure damaged

• Trees uprooted by force of the wind - destroys habitats

• Wind blown debris causes injury + loss oflife

Intense rainfall

• As tropical cyclones move over the ocean, they take up large amounts of water therefore large release of rain

• Flooding destroys habitats and contaminates groundwater + agriculture

• Damage to property + injury due to fast flowing water

Storm surge

• Tropical cyclones create an area of low pressure so sea levels rise - combined with high winds produced by a storm, large masses of water pushed towards land.

• Damage coastal defence

• Flow inwards contaminating farmland and freshwater

• Erodes coastal habitat - destroying animals habitats

  • Beaches flooded - closing of theme parks

Landslides

• Intense rainfall affects areas of high relief as well as coastal lowlands. High level of rain saturates soil making it heavy + in steep areas will not hold position, soil slides down. Where underlying rock is permeable, wet soil and rock easily slide

• Devastation of settlement at base of slope - costly repairs

• Train tracks blocks - transport delays, workforce delays

• Injury and death

• River floods landslide block channels - drought and erosion