How human activity affects natural resources, marine and wetland pollution, coral reefs, and current climate-change trends.
7 narrated scenes. Press play, listen and read along — the points appear as they are explained. Use ‹ Prev / Next › or the scene bar to jump to any scene.
The Caribbean emits very little CO₂, yet it faces some of climate change’s worst effects. Why?
Narration uses your device’s built-in voice. No sound? Switch to “Captions only” — the captions advance on their own.
Copy these into your notebook in your own words — that is how they stick.
Habitat loss, extinction, soil erosion, landslides, silting of reefs, less CO₂ absorbed, altered rainfall.
Nutrient run-off → algal bloom → algae die → decomposers use O₂ → fish suffocate.
Oil coats birds, blocks light/gas exchange. Plastics entangle, are ingested, form microplastics.
Threatened by rising sea temperature (bleaching), acidification, pollution, overfishing, silt.
Mangroves are fish nurseries, protect coastlines, filter pollutants, store carbon.
CO₂, methane, nitrous oxide trap infrared radiation. More gas → more warming.
CO₂ ≈ 423 ppm in 2024 (NOAA GML); 2025 ≈ 1.43 °C above pre-industrial; 2015–2025 the 11 warmest years (WMO 2025).
Sea-level rise, stronger hurricanes, drought, crop losses, coral bleaching, disease spread.
The kind of support a teacher gives after the lesson: worked examples to attempt first, a board illustration, key terms, common misconceptions and memory aids.
Try it in your notebook first, then reveal the solution one step at a time.
Try it in your notebook first, then reveal the solution one step at a time.
| Pollutant | Source | Effect | Control |
|---|---|---|---|
| Fertilisers | Farm run-off | Eutrophication; fish deaths | Apply correct amounts; buffer strips of plants by rivers |
| Sewage | Untreated waste | Eutrophication; disease (e.g. cholera) | Sewage treatment plants |
| Oil | Spills from ships and rigs | Coats birds’ feathers; smothers mangroves and reefs | Booms, skimmers; stricter shipping rules |
| Plastics | Litter, poor disposal | Animals entangled or eat it; microplastics | Bans, recycling, clean-ups |
| Carbon dioxide | Burning fossil fuels; deforestation | Enhanced greenhouse effect; climate change | Renewable energy; reforestation |
| Sediment | Deforestation and construction | Smothers coral reefs; blocks light | Replant slopes; silt barriers |
For any pollutant, examiners want the same three things: where it comes from, what it does, and how to reduce it.
Eutrophication chain — Fertiliser → Algae → Die → Bacteria → Oxygen down → fish Die: “FAD BOD”.
Since 2011 the Caribbean has had huge influxes of sargassum seaweed on its beaches. Scientists link these to several factors, including nutrients reaching the ocean and changing ocean conditions. The rotting weed releases hydrogen sulfide and harms tourism and fishing.
Keep a one-week “carbon diary”: note each time you travel by car or bus, use electricity or throw away plastic. Suggest three changes your household could make.
3 quick games on this lesson. Earn XP and badges as you play — your best score for each game is saved. Games are for practice and do not change your exam readiness.
8 items modelled on real CSEC Paper 1 questions. Choose one answer for each, then check. Aim for 80% or better.
Write full answers, then reveal the mark scheme and tick the points you earned (15 marks in total). Your answers are saved on this device.
Question 1 [7 marks]
Climate change and development are affecting Caribbean ecosystems.
(a) Explain ONE way in which climate change can negatively impact agriculture in the Caribbean. [2]
(b) Suggest ONE way countries can slow climate change. [1]
(c) A large construction project begins in a neighbourhood. Suggest FOUR negative environmental consequences. [4]
Question 2 [8 marks]
A hotel discharges untreated sewage close to a coral reef.
(a) Describe how the sewage could lead to the death of fish. [4]
(b) Explain TWO reasons why the loss of the reef would affect the local community. [4]
Find these in your own past-paper booklets for extra timed practice. The practice above is adapted from them.