Extreme weather events

What are the 3 tropical storms and how are they determiend?

• Hurricane

• Typhoon

• Cyclone

• Determined by region

What is a tropical cyclone?

• Large scale rotating storms that form over tropical oceans. They spin due to the deflection of moving air by the Coriolis Effect

What is the name of the area where topical cyclones form?

Source area

What is the track in tropical cyclones?

Tropical cyclones move away from the source area following prevailing winds + ocean currents.

What time period do tropical cyclones occur in the Northern Hemisphere?

June to November because oceans are warmest

What time period do tropical cyclones occur in the Southern Hemisphere?

April to November because oceans are warmest.

Attributes of a tropical cyclone?

• Ocean temperatures above 26.5 degrees celcius

• Wind increases in strength at the eye wall because of the big difference in pressure

• Storm surge in cyclone centre is caused by increased sea level due to strong surface winds pulling water up

• Warm moist air rises because it’s less dense, overtime creates eye + pulls more air to the centre

• Winds rotate outwards at the top

• Clear sky + no winds or clouds in the eye

• Dense cirrus cloud (highest cloud -icy ) canopy

• Heavy rain + strong winds in the eye wall

How do tropical cyclone start?

They start with a cluster of towering thunderstorm clouds.

In warm oceans because there’s high energy

Needs light / low crosswinds

Strong vertical currents rotating because of the coriolis effect