The physical and human importance of the oceans; the oceans as a global commons; their role in climate, biogeochemical cycles and the global economy; and the tragedy of the commons.

What this dot point is asking

Eduqas wants you to explain the physical and human importance of the oceans, explain why they are described as a global commons, and use the tragedy of the commons to show why this shared status creates problems for their management.

The answer

Physical importance of the oceans

The oceans are central to how the planet works. They regulate climate by storing and redistributing heat through ocean currents (including the global thermohaline circulation), moderating temperatures and driving weather, and by absorbing a large share of human carbon dioxide and excess heat. They are central to biogeochemical cycles: the carbon, water and nutrient cycles all run through the oceans, and marine phytoplankton produce a large share of the world's oxygen while powering the biological carbon pump. They also hold enormous biodiversity, from coral reefs to deep-sea ecosystems, underpinning marine food webs.

Human importance of the oceans

Human dependence on the oceans is profound and growing. Shipping carries the overwhelming majority of global trade, passing through strategic chokepoints (the Strait of Malacca, the Suez and Panama canals, the Strait of Hormuz) whose disruption can threaten the world economy. Fisheries are a critical food source and livelihood, especially in lower-income coastal nations. The oceans supply energy and, increasingly, are eyed for deep-sea mining of metals. These competing economic uses, alongside the oceans' physical roles, create pressure and conflict over a shared space.

The global commons and the tragedy of the commons

Because much of the ocean lies beyond national jurisdiction, the high seas are a global commons: no state owns them, and all may use them. This creates the classic tragedy of the commons: where a resource is shared and unowned, each user has an incentive to take as much as possible (catch more fish, dump more waste) because they gain the full benefit while the cost of degradation is shared by all. The cumulative result, overfishing, pollution and degradation, harms everyone, yet no individual user is motivated to restrain themselves. This is precisely why ocean management requires international governance such as UNCLOS, because no single state can manage a resource it does not own.

Examples in context

Example 1. Strategic shipping chokepoints. The oceans carry around $90\%$ of world trade by volume, and much of it funnels through narrow chokepoints such as the Strait of Malacca, the Strait of Hormuz and the Suez and Panama canals. Their strategic importance was underlined when the container ship Ever Given blocked the Suez Canal in 2021, halting an estimated $9$ billion US dollars of trade a day. Chokepoints show both the human importance of the oceans and why their security and free navigation are matters of global governance, a vivid Eduqas example of ocean dependence.

Example 2. Overfishing and the collapse of shared stocks. The collapse of the Grand Banks cod fishery off Newfoundland in 1992, and the wider decline of many high-seas stocks, illustrates the tragedy of the commons in action: open-access fishing and improving technology drove catches far beyond sustainable levels until the stock crashed, devastating the fishery and the communities that depended on it. It demonstrates why a shared, unowned resource is so vulnerable to overexploitation and why international and regional fisheries governance is essential, the standard Eduqas case linking the commons concept to a real management failure.

Try this

Q1. Define a global commons and give one example. [2 marks]

• Cue. A resource beyond the jurisdiction of any single state, shared by all humanity; examples include the high seas, the atmosphere, Antarctica and outer space.

Q2. Explain the tragedy of the commons in relation to the oceans. [3 marks]

• Cue. Because the high seas are shared and unowned, each user gains fully from taking more (fish, dumping waste) while the cost of degradation is shared by all, so the resource is overexploited and degraded for everyone, requiring international governance.