GCSE-ready- Home
- Lessons
- GCSE & IGCSE Geography A
- Tropical cyclones
Tropical cyclones
🎬 The doodle video for this lesson is coming soon. Subscribe on YouTube to see it first.
Tropical cyclones are the most powerful storms on Earth. Their impacts depend on how prepared a country is.
Where and how they form
They form over warm oceans (about 26.5 °C or warmer) between about 5° and 30° north and south of the equator.
Warm moist air rises fast, condenses and releases energy. The Earth's spin makes the storm rotate.
They are called hurricanes in the Atlantic, typhoons in the north-west Pacific and cyclones in the Indian Ocean.
Warm moist air rises fast, condenses and releases energy. The Earth's spin makes the storm rotate.
They are called hurricanes in the Atlantic, typhoons in the north-west Pacific and cyclones in the Indian Ocean.
Hazards
Strong winds damage buildings.
Storm surges raise sea level and flood the coast.
Heavy rain causes river flooding and landslides.
Storms weaken over land because they lose their supply of warm, moist air.
Storm surges raise sea level and flood the coast.
Heavy rain causes river flooding and landslides.
Storms weaken over land because they lose their supply of warm, moist air.
Impacts and responses
Impacts are often worse in poorer countries with weaker buildings and less money for warnings and evacuation.
Responses include forecasting, evacuation, storm shelters, sea walls and building rules.
Responses include forecasting, evacuation, storm shelters, sea walls and building rules.
Why do tropical cyclones lose strength over land?
- They are powered by warm, moist air from the ocean.
- Over land, that supply of energy is cut off.
- Friction with the land also slows the winds.
Answer: They lose their source of warm, moist air.
Cyclones form over oceans of at least 26.5 °C, between 5° and 30° from the equator. Hazards: wind, storm surge, heavy rain. Poorer countries usually suffer worse impacts.
Check you have got it
Answer 6 quick questions with instant marking. If you get one wrong, GCSE-ready shows you why and gives you another go. It is free, and you do not need an account.