ReviseRush logoREVISERUSH

Edexcel GCSE Geography

Weather hazards and climate change — Edexcel GCSE Geography revision

Free revision notes, key terms, common exam traps and 5 practice questions with answers. About 8 minutes to read.

Global atmospheric circulation

  • Air rises at the equator (low pressure, heavy rainfall, tropical rainforest), sinks at around 30° north and south (high pressure, clear skies, hot deserts) in the Hadley cell, with Ferrel and Polar cells completing the pattern.
  • Surface winds blow from high to low pressure and are deflected by the Coriolis effect, producing the trade winds and westerlies.
  • This circulation explains where tropical storms, deserts and rainforest belts occur — a favourite exam link.

Tropical storms

  • Tropical storms form over oceans warmer than about 26-27°C to a depth of around 60-70 m, between roughly 5° and 30° latitude where the Coriolis effect can create spin.
  • Structure: a calm, clear eye of sinking air surrounded by the eyewall of most intense winds and rain, with spiralling rain bands beyond.
  • Storms weaken over land or cool water as their energy source is removed. Climate change is expected to increase intensity and possibly change distribution as more oceans reach the threshold temperature.

Key terms

Global atmospheric circulation
The worldwide pattern of rising and sinking air that creates pressure belts and winds.
Coriolis effect
The deflection of moving air caused by the Earth's rotation.
Eye
The calm, low-pressure centre of a tropical storm where air sinks.
Eyewall
The ring of towering cloud around the eye with the strongest winds and rain.
Storm surge
A rise in sea level caused by low pressure and strong onshore winds.
Mitigation
Action to reduce the causes of climate change, mainly greenhouse gas emissions.

Common exam traps

  • Saying tropical storms form at the equator — the Coriolis effect is too weak within about 5°, so they form slightly poleward of it.
  • Describing the eye as the most destructive part; the eyewall is.
  • Confusing mitigation (tackling causes) with adaptation (coping with effects).

Practice questions with answers

  1. 1. Hot deserts are found near 30° latitude because air there is:

    • • Rising and cooling
    • • Sinking and warming
    • • Static and humid
    • • Rising and moist

    Answer: Sinking and warming

    Descending air warms, holds more moisture and prevents cloud formation.

  2. 2. Minimum sea-surface temperature needed for tropical storm formation is about:

    • • 16°C
    • • 21°C
    • • 27°C
    • • 35°C

    Answer: 27°C

    Warm water supplies the latent heat that powers the storm.

  3. 3. Explain why tropical storms weaken over land.

    Answer: They lose their supply of warm, moist ocean air and friction slows the winds

    Energy source removal is the key idea.

  4. 4. Which part of a tropical storm has sinking air and clear skies?

    • • Eyewall
    • • Rain bands
    • • Eye
    • • Outflow

    Answer: Eye

    Air sinks in the eye, giving a temporary calm.

  5. 5. Give two primary effects of a tropical storm.

    Answer: Buildings destroyed by wind; flooding from surge and rainfall causing deaths

    Primary effects are the direct destruction from wind, rain and surge.

Keep going in the app

This topic has 51 questions in total, plus flashcards, cram mode and Grade 9 Push challenges.

Open the full topic Quick-fire quiz

More free Geography revision

ReviseRush is an independent educational revision aid. It is not affiliated with, endorsed by or connected to AQA, Edexcel, OCR, WJEC, Pearson or any exam board. All notes and questions are original. Always check content against your official course and specification. No grade outcome is guaranteed.