Core 2 • Section 2.2

Consequences of Global Climate Change

A connected cascade of physical, ecological and human consequences—unevenly experienced across places and societies.

Syllabus link

Effects on places, societies and environmental systems

01
Systems enquiry

A cascade of consequences

Climate hazards interact with exposure and vulnerability rather than producing identical outcomes everywhere.

Begin with a physical change, then follow its knock-on effects through ecosystems, livelihoods, health, migration and trade. Avoid a simple list: ask how one consequence becomes the cause of another.

DriverWarming
Physical changeIce melt
HazardSea-level rise
Human effectDisplacement

Climate domino challenge

Build a six-link chain, then mark where adaptation could interrupt it. Add one feedback and one uncertainty.

02
Cryosphere & oceans

Ice, oceans and sea levels

Thermal expansion and melting land ice raise sea level; shrinking glaciers affect freshwater supply.

Distinguish floating sea ice from land-based glaciers and ice sheets. Sea-level rise is not spatially uniform, and consequences depend on subsidence, storm surges, coastal protection and population exposure.

NASAUnderstanding sea-level rise
ExploreCoastal Risk Screening Tool
03
Environmental systems

Carbon stores, biomes and habitats

Ocean, soil, vegetation and permafrost stores can weaken or become sources as climate changes.

Warmer oceans absorb less carbon dioxide; acidification affects marine food webs. Shifting climate zones alter habitats, species ranges, wildfire regimes and ecosystem services.

SystemThe carbon cycle
Ocean changeOcean acidification
04
Hazards & livelihoods

Extreme weather and agriculture

Changing frequency, magnitude and geography of heat, drought, heavy rainfall and some storms.

Climate change influences hazards differently, so avoid claiming it “causes” every event. Use attribution evidence. Agriculture faces heat stress, water scarcity, changing pests and yield variability, with possible gains in some cooler regions.

Attribution audit

  1. State the observed event.
  2. Identify the climate variable involved.
  3. Separate hazard from exposure and vulnerability.
  4. Assess how confidently the event can be attributed.
05
People & places

Health, inequality and migration

Health risks and population movements emerge through interacting environmental and social pathways.

Heat illness, changing disease vectors, food insecurity, smoke and mental-health impacts are mediated by income, age, housing and access to care. Climate mobility includes temporary displacement, internal migration, planned relocation and immobility.

06
Place case study

Kiribati and climate mobility

Low-lying atolls reveal how sea-level rise, freshwater, culture, sovereignty and migration interact.

Kiribati is not simply a story of “climate refugees.” Investigate local adaptation, labour mobility, the former “migration with dignity” policy, land and identity, and the agency of I-Kiribati communities.

Case-study enquiry

  1. Map the physical exposure of Kiribati.
  2. Explain two social or economic vulnerabilities.
  3. Compare in-situ adaptation with planned mobility.
  4. Evaluate the phrase “migration with dignity.”
07
Global connections

Trade and Arctic transport routes

Reduced sea ice may shorten routes while creating ecological, geopolitical and navigational risks.

Assess possible shipping-time and fuel savings against unpredictable ice, limited infrastructure, environmental damage, Indigenous rights and new geopolitical tensions.

2050 scenario synthesis

Create a “postcard from the future” for one coastal city, island state or Arctic community. Combine physical evidence with health, migration, trade and justice consequences. Label it as a scenario—not a prediction.