O Level Geography Physical Geography Quiz

O-Level Geography Quiz - Answer Key (Physical Geography)

Topic: Physical Geography
Level: O-Level
Version: 1 of 5 (syllabus-first practice; not past-year derived)

Section A Answers

Q1 [2 marks]

• Weather is the short-term atmospheric condition (e.g., daily rainfall, temperature) at a place.
• Climate is the long-term average weather pattern (usually over 30 years) for a region.
  (1 mark each point)
  Teaching note: Students often confuse the time scale; emphasise “weather = day to day, climate = long term average”.

Q2 [1 mark]
Atmospheric circulation (or global atmospheric circulation / convection cells).
Accept: convection, wind systems transferring heat.

Q3 [2 marks]

• Sea has high heat capacity, absorbing heat slowly in day and releasing at night, moderating temperature.
• This reduces daily and annual temperature range compared to inland areas.
  (1 mark for sea moderating effect, 1 mark for lower range outcome)

Q4 [1 mark]
Carbon dioxide (CO₂) / Methane (CH₄) / Nitrous oxide (N₂O).
Any one correct GHG from human activity.

Q5 [3 marks]
From diagram:

• Composite volcano has steep sides formed by alternating layers of ash and lava (1 mark).
• It has a central vent connecting magma chamber to crater; may have secondary vent (1 mark).
• Explosive eruptions due to viscous lava (1 mark if inferred from layers).
  Marking: 2 features described = 2 marks; third for process link.

Q6 [2 marks]

• At constructive boundary, plates move apart (1 mark).
• Magma rises to fill gap, cools and solidifies forming new crust (1 mark).
  Example: Mid-Atlantic Ridge.

Q7 [1 mark]
Loss of tourism income / destruction of farms / cost of rebuilding / job loss.
Any one economic impact.

Section B Answers

Q8 [2 marks]

• Use a bar chart with three bars (A, B, C) on x-axis and wind speed (km/h) on y-axis (1 mark).
• Or overlay line graph if repeated measures; label legend clearly (1 mark).
  Teaching: One combined graph, not three separate.

Q9 [3 marks]

• Annual range = highest mean – lowest mean = 21.0 (Jul) – 4.0 (Jan) = 17.0 °C (1 mark for calc, 1 mark for value).
• Shows temperate city has large seasonal temperature variation, unlike Singapore’s narrow range (~1°C) (1 mark).
  Working: 21.0 − 4.0 = 17.0 °C.

Q10 [2 marks]

• Convergent boundary: Pacific Ring of Fire / Himalaya (1 mark).
• Creates volcanic arcs / fold mountains (1 mark).

Q11 [4 marks]

• Trend: global temp anomaly rises from −0.1 °C (1980) to +0.9 °C (2020), clear warming (2 marks for description).
• Human cause: burning fossil fuels increasing CO₂, enhancing greenhouse effect (2 marks).
  Marking descriptors: trend 2m, cause 2m.

Q12 [2 marks]

• Increase sample size (e.g., 30 pebbles per site) (1 mark).
• Use calliper for precision / repeat measurements (1 mark).
  Improves reliability by reducing random error.

Q13 [3 marks]

• Waves attack base of cliff at high tide line, eroding via hydraulic action (1 mark).
• Undercutting forms wave-cut notch, cliff retreats (1 mark).
• Exposed platform left at low tide as wave-cut platform (1 mark).
  Ref to diagram required.

Q14 [2 marks]

• Bar chart with 4 bars for locations, y-axis average rainfall (mm) (1 mark).
• Or grouped line graph if over time; clear labels (1 mark).

Section C Answers

Q15 [4 marks]

• Human activities (deforestation, fossil fuels) increase GHGs like CO₂ (1m).
• GHGs trap outgoing infrared radiation, enhancing natural greenhouse effect (1m).
• More heat retained → global temperatures rise (1m).
• Leads to climate change: ice melt, sea level rise, weather shifts (1m).
  Structure: cause → mechanism → impact.

Q16 [5 marks]

• Strength: systematic sampling every 10 m reduces bias, covers transect (1m).
• Strength: 15 pebbles/site adequate for basic trend (1m).
• Weakness: 80 m too short to show full gradient (1m).
• Weakness: ruler less precise than calliper; only one beach limits generalisation (1m).
• Conclusion: partially effective; improve length & multiple sites (1m).
  AO3 evaluation expected.

Q17 [4 marks]

• Describe: flat/gentle slope sandy beach, vegetation at back, no cliff (2m).
• Formation: deposition of sand by waves in low-energy environment; vegetation stabilises (2m).
  Must refer to photo features.

Q18 [6 marks]

• Destructive margin: oceanic plate subducts under continental (1m).
• Friction causes stress release → earthquakes (1m).
• Subducted plate melts, magma rises → volcanoes (1m).
• Example: Pacific Ring of Fire / Japan (1m).
• Link both hazards to same process (2m for synthesis).
  Marking: process 3m, example 1m, synthesis 2m.

Q19 [4 marks]

• Advantage: GIS overlays historical shorelines to show erosion rate accurately (2m).
• Limitation: needs high-quality data and trained users; costly (2m).
  Balance required.

Q20 [6 marks]

• Agree: sea level rise floods low islands, freshwater lens salinised (2m evidence).
• Other threats: storms, economic reliance (1m).
• Disagree extent: local governance, adaptation can reduce risk (2m).
• Judgement: serious but not sole threat; combined action needed (1m).
  AO3: balanced + reasoned conclusion.