Antarctica as a global commons

The geography of Antarctica and the Southern Ocean

[This is the first of three posts over the coming weeks on Antarctica as a global commons.]

Antarctica is the Earth’s most southern continent containing the geographic South Pole. It is almost entirely south of the Antarctic Circle and is surrounded by the Southern Ocean. Its size is estimated to be 14 million km², making it the fifth-largest continent. It is twice the size of Australia. A total of 98% of the land area is covered by ice, which averages almost 2km in thickness, and this ice extends to all but the most northern reaches of the Antarctic Peninsula (Figure 1).

Figure 1. Physical map of Antarctica

Antarctica is the coldest, driest, and windiest of all the Earth’s continents, and has the highest average elevation. Climatically, it is a desert, with an annual precipitation of only 200mm along the coast, with lower totals inland. Around the coasts temperatures are generally close to freezing in the summer months (December–February), or even slightly positive in the northern part of the Antarctic Peninsula. During winter, monthly mean temperatures at coastal stations are between −10°C and −30°C but temperatures may briefly rise towards freezing when winter storms bring warm air towards the Antarctic coast.

Conditions on the high interior plateau are much colder because of its higher elevation, higher latitude and greater distance from the ocean. Here, summer temperatures struggle to get above −20°C and monthly means fall below −60°C in winter.

The distribution of precipitation over Antarctica is varied, with several metres of snow falling each year near the coast, but the interior only getting an annual snowfall of a few centimetres. After the snow has fallen it will be redistributed by the winds, particularly in the coastal areas where down-slope katabatic winds blow.  The continent generally experiences moderate winds, with mean wind speeds of around 6 ms^-1, but in gales, which can occur on over 40 days a year, mean speeds can exceed 30 ms^-1 with gusts of over 40 ms^-1. The strong katabatic winds, caused by the flow of cold air off the central plateau, make some coastal sites around Antarctica the windiest places in the world. 

There are no permanent human residents, but between 1,000 and 5,000 scientists live there at any one time at research stations scattered across the continent. There is a variety of flora and fauna present, consisting of algae, bacteria, fungi, some plants, and animals ranging in size from mites and nematodes to penguins and seals. Where vegetation does occur, it can be classed as tundra.

Antarctica is governed by parties to the Antarctic Treaty System (ATS), each of which has consulting status. The Antarctic Treaty was signed in 1959 by 12 countries, and since then a further 38, including India and China, have signed. The treaty prohibits military activities and mineral mining, prohibits nuclear explosions and nuclear waste disposal. It supports scientific research and protects the continent's ecology. The intention of the treaty is to protect the continent’s vulnerability to the threats from both economic pressures and environmental change.

Threats to Antarctica

Climate change

According to the Intergovernmental Panel on Climate Change (IPCC), Antarctica is facing the loss of ice from its huge ice sheet, especially from the Antarctic Peninsula [Figure 4]. Furthermore, there is growing evidence of the ice shelves around the continents becoming unstable - for example, large cracks have appeared in the Ross Ice Shelf. 

The impact of climate change will vary across the continent:

(a) The East Antarctic Ice Sheet (EAIS) is thought to be very stable due to its extremely cold temperatures. If the temperature increased by a few degrees, it is still far too cold for surface melting, and so the ice sheet would not shrink. Only if the temperature went up by huge amounts (tens of degrees) would it be possible for major melting to begin. Most scientists working on the Antarctic ice sheets think that the EAIS will not collapse or cause a significant sea-level rise for many centuries to come.

(b) The West Antarctic Ice Sheet (WAIS) is the opposite - it is unstable. The fact that much of the ice sits below sea level means that it is sensitive to small rises in sea level, which can cause it to thin. Moreover, the WAIS is drained by several ice streams – fast moving ‘rivers’ of ice very different from the slow-moving ice of the rest of the Antarctic ice sheets on the EAIS. Because they move so fast and drain so much of the ice in the WAIS, the ice streams have the potential to rapidly increase the amount of ice being lost from the ice sheet to the ocean.

(c) The Antarctic Peninsula (AP) is one of the most rapidly warming places in the world. Air temperatures here have increased by 3°C over the last 50 years. This warming has been associated with the strengthening of the winds that encircle Antarctica, which in turn drives changes in oceanic circulation and increased upwelling of circumpolar deep water within the Southern Ocean. Across the AP, some 90% of glaciers are receding. The most pronounced impact has been the collapse of some AP ice shelves. Warmth has caused extra melting on the surface of the ice shelves, and eventually this leads to break-up.

Fishing and whaling

Whaling for meat oil and whalebone caused whaling stations for meat processing to be set up in the late nineteenth century on the islands of South Georgia and South Shetland in the Southern Ocean. As whales, especially the blue whale, began to die out many countries stopped the trade.

Fishing became the main economic use of the seas during the 1960s and 1970s, during which large Russian and Japanese fishing fleets fished rock cod and krill stocks using large industrial-scale trawlers. However, by the late 1970s these fisheries had collapsed. Subsequently through the 1980s and to the present day the dominant exploited biomass is krill.

All these fisheries are now regulated through the Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR) which came into existence in 1982. A central objective of Antarctic marine research is to provide scientific support for the work of CCAMLR. It is suggested that the place of krill in the ecology of the area is crucial - if the krill disappear then the whole of the food chain will collapse.

Recently, controversy has arisen between members of the ATS. China and Russia favour greater exploitation of fishing resources, whereas other parties, such as the UN and environmental NGOs, want to see the establishment of marine protected areas (MPAs) which seek to conserve biodiversity. One such MPA was agreed for the Ross Sea in 2017.

The search for mineral resources

The initial Antarctic Treaty did not address the regulation of mineral resource activities. There are many resources as yet undeveloped on Antarctica including oil, coal and many metals. The UK and New Zealand first raised the issue of control of possible future mining within the ATS in 1970, as mineral companies had approached the two countries regarding possible commercial geophysical exploration in the Southern Ocean. The regulation of mineral activities became a very controversial issue.

A new Protocol on Environmental Protection to the Antarctic Treaty (known as the Madrid Protocol) was eventually signed in 1991. The Madrid Protocol bans all mineral resource activities in Antarctica (other than for scientific research). The ban can be revisited in 2048, although some countries (e.g. USA, Russia, and China) have stated that they want to revisit the ban sooner.

Tourism and scientific research

The development of small-scale tourism began in Antarctica in the 1950s, with commercial tour operators providing passenger ships. The first specially designed, ice-strengthened cruise ship, the Lindblad Explorer, visited in 1969. Since then, the industry has grown considerably, with numbers of tourists increasing from under 9,000 in 1992/93 to over 55,000 in 2018/19. Tourists go to see the wildlife and, as this activity is relatively small-scale, it could be argued to be sustainable. However, the summer is the breeding season for most of the wildlife they visit, and any disturbance could upset the balance. There is also pressure on the landing sites which receive most tourists, especially the old whaling stations and historic sites such as McMurdo Sound, where the original huts from Scott’s expedition in 1912 are located.

All tour operators providing visits to Antarctica are members of the International Association of Antarctica Tour Operators (IAATO), which seeks to ensure that tourism in Antarctica is conducted in an environmentally friendly way. The British Antarctic Survey (BAS) also welcomes a small number of visits to its stations during the austral summer, and groups are given a guided tour of the facilities, where they can learn about the scientific research the BAS undertakes.