4.3.2 Impacts of Human Activity on Antarctica
Wildlife Disturbance: Frequent visits to penguin colonies can increase stress levels in birds, leading to lower reproductive success or nest abandonment. Guidelines often mandate a minimum distance (e.g., 5 meters), but cumulative foot traffic still erodes fragile moss banks and lichens that take decades to grow.
Invasive Species Introduction: Tourists and scientists inadvertently transport seeds, spores, and insects on their clothing, boots, and equipment. As the Antarctic Peninsula warms, these non-native species are more likely to survive and outcompete native flora and fauna.
Vessel Impacts: The rise in cruise ship traffic increases the risk of maritime accidents in poorly charted, ice-filled waters. Large vessels also contribute to 'black carbon' deposits on snow, which reduces albedo and accelerates localized melting.
Climate Warming: Antarctica is one of the fastest-warming regions on Earth. Rising temperatures lead to the collapse of ice shelves, which act as buttresses for land-based glaciers; their removal accelerates sea-level rise globally.
Ocean Acidification: The Southern Ocean absorbs a disproportionate amount of anthropogenic . This increases acidity, which interferes with the ability of calcifying organisms like pteropods (sea butterflies) and krill larvae to form shells, threatening the base of the entire food web.
Ozone Depletion: While recovering due to international agreements, the annual 'Ozone Hole' caused by CFCs increases UV-B radiation. This radiation can damage phytoplankton, the primary producers of the Antarctic sea, reducing the total biomass available for higher trophic levels.
The Antarctic Treaty (1959): This international agreement sets Antarctica aside as a scientific preserve, bans military activity, and suspends all territorial claims. It provides the legal foundation for all subsequent environmental regulations.
The Madrid Protocol (1991): Formally known as the Protocol on Environmental Protection to the Antarctic Treaty, it designates Antarctica as a 'natural reserve, devoted to peace and science.' It prohibits all mining and mineral extraction indefinitely.
Environmental Impact Assessments (EIA): Under the Madrid Protocol, any proposed activity (scientific or touristic) must undergo a rigorous evaluation to determine its potential impact. Activities with more than a 'minor or transitory' impact require comprehensive multi-national review.
Distinguish Scales: When asked about impacts, clearly categorize them into 'Local/Direct' (e.g., sewage from a base) and 'Global/Indirect' (e.g., ocean acidification). This demonstrates a sophisticated understanding of environmental geography.
Focus on Fragility: Always mention the 'slow recovery rate' or 'low resilience' of the environment. In exams, explaining why an impact is significant (e.g., moss taking 50 years to recover from a footprint) earns more marks than just listing the impact.
Legal Knowledge: Be prepared to cite the Madrid Protocol specifically regarding the ban on mining. It is a frequent focal point for questions regarding the future protection of the continent.
Verify Logic: If discussing melting ice, distinguish between sea ice (which doesn't raise sea levels) and land-based ice/ice shelves (which do). Misidentifying these is a common error that loses marks.