Antarctica (GSGG) Flashcards
Location
- Rocky, mountainous continent and contains 90% of the world’s land ice.
- 4th largest continent.
- Unevenly divided into East (Greater) Antarctica and West (Lesser) Antarctica by the Transantarctic Mountains.
Antarctic Convergence
A natural boundary around Antarctica where the cold, northward-flowing Antarctic waters meet the relatively warmer waters of the sub-Antarctic.
Climate
- Average temperature = -50°C, can be as low as -89°C.
- Precipitation = very low, less than 50 mm per year in the interior.
Biodiversity
- Cold, dry climate and limited availability of sunlight = biological productivity is very low, with vegetation mostly limited to moss and lichens.
- The Southern Ocean is an exception = higher rates of productivity due to phytoplankton.
Threats - CLIMATE CHANGE
- West Antarctica’s ice sheet is smaller and more vulnerable = glacial ice is more likely to slide into the sea > raise global sea levels by 5 m.
- Impacts of ocean warming = changing distribution of penguin colonies and decline in Antarctic krill.
- ocean acidification = waters may become corrosive to unprotected shells and skeletons > loss of organisms and disrupt food web.
Threats - FISHING
- Fishing replaced whaling = Russian and Japanese exploitation of the Southern Ocean for rock cod and krill.
- Research shows that krill numbers have dropped by about 80% since the 1970s.
- Fishing ships may directly destroy marine habitats and contaminate water by dumping waste.
Threats - SCIENTIFIC RESEARCH
- Vital for research into climate change where ice cores have been extracted to include ice that is up to 400,000 years old.
- Scientists are well-briefed about the need for care of the environment and are mainly invested in its protection.
- Many research stations are seasonal = BAS’s Port Lockroy research station is manned between November and March.
Threats - TOURISM
- Risen from less than 2000 per year in 1980s to 27,000 in 2011-2012.
- Lindblad Plan = groups are divided into boatloads of around 20 people with an expert guide, with each around 200 possible sites only visited every 2 to 3 days to minimise impacts.
- Concerns = fragile ecosystem can be disturbed in the long-term, summer tourist season coincides with peak wildlife breeding periods, future development of land-based tourism.
Threats - MINERAL RESOURCES
- There has never been any commercial mining and this is banned by the Antarctic Treaty, however future demand for resources is likely to put pressure on the vast reserves found on the continent.
- Known mineral deposits = coal, oil manganese, titanium and even gold and silver.
- Any mineral exploitation would have to overcome the seriously hostile environment = major problems of inaccessibility, the extreme climate and deep covering of moving ice sheets and glaciers.
Resilience
- Gives an ecosystem the ability to recover from shock events, disturbances or ongoing change.
- E.g. sealing, whaling and hunting penguins pushed species to the brink of extinction, but once these activities ceased, many species recovered and others thrived (e.g. king penguin).
Adaptation
- Linked to the ability of an ecosystem to return to an equilibrium status.
- E.g. some organisms may benefit from climate change in the short term, while others will be vulnerable as their ability to adapt is slower and environmental change is happening too quickly for them.
Mitigation
- Intervention by humans to eliminate or reduce the impacts presented by these threats.
- For Antarctica, this requires governance of a continental land mass with agreements at a global level, so that mitigation efforts are effective.
The Antarctic Treaty (AT) - 1959
- to be used exclusively for peaceful purposes; military activities are banned.
- promotes international scientific cooperation including the exchange of research plans and personnel and sharing of research results.
Criticisms:
- not mandatory = countries can choose to sign it.
- includes a dispute settlement procedure and a review mechanism by which the treaty can be modified.
The Madrid Protocol - 1991
- Designates Antarctica as a ‘natural reserve, devoted to peace and science’.
- Bans all activities relating to mineral resources.
- Ban on mining can only be modified if all parties agree = next review is due in 2048, any modifications are unlikely beforehand and only then if 75% of the consultative parties agree.
International Whaling Commission (IWC) - 1946
- Responsible for the conservation of whales and the management of whaling activities.
- Introduced Whaling Moratorium in 1982 = banned all commercial whaling on all species and all populations.
Criticisms:
- member states choose to freely be in the IWC, as well as opt out = no penalties for member leaving, e.g. Japan left in 2018 to resume commercial whaling in its own territorial waters and exclusive economic zone (EEZ).
- countries can object to the IWC’s regulations, e.g. Norway and Iceland continue to hunt common minke whales commercially within their own EEZ, but neither takes whales from the Southern Ocean.
