What does Global Systems and Global Governance cover?

This A2 unit links global natural systems to their governance. It covers the global water cycle and water insecurity, the carbon cycle and its connection to energy security and climate change, the global governance of the oceans as a commons, and the patterns, impacts and governance of global migration. The unifying theme is how global systems operate and how international institutions, laws and agreements attempt to manage them.

How is this unit examined in WJEC A-Level Geography?

It is assessed in the A2 Unit 3 written paper with data-response and structured questions plus extended responses. Expect to explain how a global system works (stores and flows), analyse causes and impacts of insecurity or change, and assess the effectiveness of governance. The unit is synoptic, so links between water, carbon, oceans and migration are rewarded, along with located examples.

What does global governance mean here?

Global governance is the set of rules, norms, laws and institutions, operating from international to local scales, that manage shared global systems and commons. Examples include UNCLOS for the oceans, the Paris Agreement for carbon, integrated water-resource management for water, and UN frameworks and national policy for migration. A recurring exam task is assessing how effective this governance is.

What are the most common mistakes in this unit?

Frequent errors are saying most of Earth's water is freshwater, confusing the global cycle with the local drainage basin, treating carbon as only atmospheric, saying the oceans are ungoverned, and treating all migrants the same. Examiners also penalise listing solutions without assessing effectiveness, so always evaluate governance.

How should I revise this unit?

Learn each system as stores and flows, then layer the human dimension (insecurity, climate change, threats, migration drivers) on top, and finish with the multi-scalar governance and an honest assessment of effectiveness. Build a small bank of located examples (a drainage basin, a carbon or energy case, an ocean threat, a migration corridor) and rehearse synoptic links between the four topics.

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WJEC A-Level Geography Global Systems and Global Governance (A2 Unit 3): a deep dive on the water and carbon cycles, ocean governance and global migration

A deep-dive WJEC A-Level Geography guide to Global Systems and Global Governance (A2 Unit 3). Covers the water cycle and water insecurity, the carbon cycle and energy security, the global governance of oceans, and global migration, with UK, Welsh and global examples and the exam patterns WJEC repeats.

Generated by Claude Opus 4.819 min readWJECUpdated 2026-06-02

Reviewed by: AI editorial process; not yet individually human-reviewed

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What this unit actually demands
The water cycle and water insecurity
The carbon cycle and energy security
The global governance of oceans
Global migration
How this unit is examined
Check your knowledge

What this unit actually demands

Global Systems and Global Governance is the A2 unit that connects global natural systems to the institutions that govern them. You learn how the water and carbon cycles work, how the oceans function as a commons, and how people move across the world, then analyse the insecurity, change and threats these produce, and assess how effectively they are governed. Examiners test systems understanding (stores and flows), analysis of causes and impacts, and evaluation of multi-scalar governance, with located examples and synoptic links.

This guide ties together the four dot-point pages for the unit: the water cycle and water insecurity, the carbon cycle and energy security, the global governance of oceans, and global migration. Each has its own page with practice questions; this overview shows how they connect.

The water cycle and water insecurity

The global water cycle moves water between stores (oceans, ice, groundwater, atmosphere) through evaporation, condensation, precipitation and runoff; most water is saline ocean. At the drainage-basin scale, inputs, flows and outputs set the water balance and the storm hydrograph. Water insecurity arises from physical causes (drought, climate variability) and human causes (population, irrigation, pollution, over-abstraction), threatening health, food and the economy, and is managed by supply schemes (dams, transfers, desalination) and demand-side sustainable strategies.

The carbon cycle and energy security

The global carbon cycle stores carbon in the atmosphere, oceans, biosphere and lithosphere and moves it by photosynthesis, respiration, decomposition, combustion and ocean exchange. Burning fossil fuels for energy shifts carbon to the atmosphere, enhancing the greenhouse effect and driving climate change, so the carbon cycle and energy security are linked. Responses combine mitigation (renewables, nuclear, carbon capture, afforestation, efficiency) and adaptation, governed from the Paris Agreement down to the UK net-zero target and Welsh climate commitments.

The global governance of oceans

The oceans are a global commons prone to the tragedy of the commons. Threats include overfishing, plastic and chemical pollution, acidification, warming, and competition over seabed resources and shipping. Governance is multi-scalar: UNCLOS defines territorial waters and exclusive economic zones; regional fisheries bodies, the International Maritime Organization, marine protected areas and the High Seas treaty add rules. Effectiveness is uneven, because enforcement on the high seas is weak and sovereignty limits cooperation.

Global migration

Global migration is shaped by push and pull factors and globalisation, producing flows of economic migrants, refugees and skilled workers. Impacts differ for source areas (remittances but brain drain and ageing) and host areas (labour and growth but service pressure and tension). Governance is multi-scalar, from national immigration policy and EU free movement to UN refugee frameworks, and is politically contested.

How this unit is examined

A typical WJEC profile for this unit:

Systems questions. Describe stores and flows of the water or carbon cycle, or the structure of a drainage basin.
Cause and impact. Analyse the causes and impacts of water insecurity, climate change, ocean threats or migration.
Governance evaluation. Assess the effectiveness of governance (UNCLOS, Paris, water or migration policy).
Synoptic links. Connect the four topics, for example carbon and climate change driving water insecurity and migration.

Check your knowledge

A mix of systems, analysis and governance questions covering the whole unit. Attempt them under timed conditions, then check against the solutions.

Define the water balance of a drainage basin. (2 marks)
Explain one human cause of water insecurity. (3 marks)
Name two natural processes that transfer carbon between stores. (2 marks)
Explain how burning fossil fuels links energy use to the carbon cycle. (3 marks)
Define the term global commons. (2 marks)
Explain one reason why governing the high seas is difficult. (3 marks)
Distinguish between a push factor and a pull factor in migration. (2 marks)
Assess the effectiveness of global governance in managing one shared global system. (4 marks)

Solutions

Q1: Precipitation minus evapotranspiration minus the change in storage, which governs runoff and river discharge.
Q2: Over-abstraction of rivers or aquifers for irrigation and supply removes water faster than it is replenished, lowering water tables and reducing availability.
Q3: Any two of photosynthesis, respiration, decomposition, combustion or ocean-atmosphere exchange.
Q4: Combustion transfers carbon from the long-term lithosphere store to the atmosphere as carbon dioxide, raising its concentration, enhancing the greenhouse effect and driving climate change.
Q5: A resource or area, such as the high seas, the atmosphere or Antarctica, that lies beyond the jurisdiction of any single state and is shared in principle by all humanity.
Q6: No state has sovereignty over the high seas, so enforcement is weak and users have an incentive to overexploit shared resources (the tragedy of the commons).
Q7: Push factors drive people away from a source area (unemployment, conflict); pull factors attract them to a destination (jobs, safety).
Q8: For the oceans, UNCLOS, regional fisheries bodies, marine protected areas and the High Seas treaty set important rules and some stocks have recovered, but enforcement on the high seas is weak, illegal fishing and pollution persist, and sovereignty limits cooperation, so governance is partially effective, stronger within national waters than on the open ocean.