Option B • Section 1
Ocean–Atmosphere Interactions
The physical processes linking ocean circulation, atmospheric circulation, climate variability and coastal hazards.
Interactions between oceans and the atmosphere, including ENSO, tropical cyclones and the ocean carbon cycle
Ocean systems and currents
Differential heating, pressure belts, wind and the Coriolis effect drive connected atmospheric and ocean circulation.
Surface currents redistribute heat, nutrients and organisms. Their direction reflects prevailing winds, continental barriers and Earth’s rotation; deeper circulation responds to density differences created by temperature and salinity.
Current-map enquiry
- Identify two major warm and two cold currents.
- Describe their direction and coastal influence.
- Explain the pattern using winds, Coriolis and continents.
- Predict one ecological or climatic consequence.
El Niño and La Niña
ENSO alters Pacific pressure, winds, upwelling, rainfall and hazards across connected regions.
Build the ENSO system
Create paired normal/El Niño diagrams showing trade winds, thermocline, upwelling and rainfall. Add consequences for Peru, Australia or Southeast Asia and one teleconnection beyond the Pacific.
Tropical cyclones
Warm water, moisture, low wind shear and Coriolis allow cyclones to develop and intensify.
Separate the hazard—wind, storm surge and rainfall—from exposure and vulnerability. Climate change affects cyclone rainfall, intensity and coastal flooding, but not every storm in the same way.
Hazard pathway
Explain formation as a sequenced process, then annotate where ocean temperature, wind shear, storm surge, coastal topography and settlement patterns affect the final risk.
Typhoon Haiyan
A powerful tropical cyclone, catastrophic storm surge and uneven recovery in the Philippines.
Disaster-recovery briefing
Classify impacts and responses by timescale. Recommend three short-term and three long-term priorities, then justify how recovery could reduce future vulnerability.
Oceans, carbon and acidification
The ocean stores and exchanges carbon, moderating climate while changing seawater chemistry.
Dissolved carbon dioxide forms carbonic acid, reducing pH and carbonate availability. Effects vary among species, but shell-building organisms and coral-reef systems can be especially vulnerable.
Causal-chain task
Trace fossil-fuel combustion → atmospheric CO₂ → ocean uptake → chemistry change → biological and socioeconomic consequences. Mark one uncertainty and one management response.