Written by Rebecca Greatorex
The Antarctic, as one of the most pristine environments on earth, is under the protection of a treaty agreed to by many countries to protect and preserve it. The Antarctic Treaty System (ATS) protects everything south of 60oS which includes the entirety of the Antarctic Continent. It was implemented to highlight the importance of the Antarctic for scientific research, its “wilderness and aesthetic” value, and the importance of its ecosystems in terms of human living resources.
The risk level of the Antarctic is calculated based off positive and negative impacts of climatic (temperature) and non-climatic (fishing/ tourism) drivers on ecosystem services. The Antarctic and its oceans provide globally important ecosystem services and benefits. It is imperative that these are preserved.
This article relates directly to a recently published review associated with the British Antarctic Survey titled ‘Future risk for Southern Ocean ecosystem services under climate change’. The paper utilises the Special Report on the Ocean and Cryosphere in a Changing Climate (SROCC) to predict how key drivers of environmental change threaten the ecosystem services of the Antarctic. The study focuses on the combined effects of these drivers on three ecosystem services; the blue carbon pathway, the Antarctic krill fishery, and Antarctic tourism. It also considers how future demand and distribution of these services may change and how best to manage negative climate-related impacts.
The Blue Carbon Pathway
The blue carbon pathway refers to two methods of carbon storage within the ocean; storage within the bodies of organisms (this is typically less than 100 years) and sequestration in the sediment (typically far more than 100 years). Carbon capture is increasing in the polar regions are a result of sea ice loss, glacier retreat and increased primary productivity. This is contrary to most other ocean ecosystems where habitat destruction and pollution are decreasing their blue carbon potential. Whilst melting of the ice is clearly a bad thing, increase in carbon capture in polar regions may help to offset the negative effects of carbon loss in other global ecosystems.
Blue carbon storage increases with phytoplankton density which in turn increases with sea ice loss, but there are several factors to be aware of. Not only is sea ice melt limited by finite ice in polar regions, ice melt does also not occur over winter due to a lack of sunlight and photosynthesis.
Current management policy within the ATS is not sufficient to protect the Antarctic against further sea ice loss so the future projection of carbon storage in the Antarctic is uncertain. Large areas of the Antarctic are unused, and these habitats would be ideal for protection as they provide a negative feedback loop for climate change. However, quantifying the actual positive effects of protecting these areas is difficult, time consuming, and expensive.
The Antarctic Krill Fishery
The Antarctic krill (Euphausia superba) is a pelagic crustacean living in vast shoaling communities in the polar seas. These krill have an extremely high combined biomass and provide a food source for popular tourism organisms such as whales. They are also fished by for fishmeal, aquaculture and omega-3 supplements. The current exploitation of the krill fishery is limited by area and depth, i.e. fishing takes place within a certain geographic location and within a certain depth range. Under current climate conditions, the fishery is theoretically capable of being fished to a much greater extent. This is rare for marine fisheries and may make it a viable option for the future, but this must be carefully considered.
Climate change is expected to reduce krill habitat and the productivity of the population as a result of direct physiological stress. pH and temperature both impact the embryonic and larval development of krill. Alongside this, krill life cycles are strongly linked to seasonal change which is a particularly big issue with current climate change offsetting usual weather patterns. Other factors, such as the recovery of the whale populations, may also affect overall krill stocks. All these variables must be considered before further exploitation of the species.
Antarctica, largely inaccessible, has a small but growing tourism industry. It’s ‘pristine’ habitat, charismatic wildlife and spectacular views attract cruises throughout the summer season. Much of the tourism is dependent on the close proximity of wildlife such as penguins, walruses and whales. In 2019/20, tourism generated over $600 million. Part of this profit goes towards conservation making tourism an essential ecosystem service.
However, increases in tourism may make the Antarctic vulnerable to over-exploitation via loss of wildlife, introduction of non-native species, pollution, and disturbance. A large part of selling trips to Antarctica includes advertising to see it before it is gone. However, an increase in tourism traffic may reduce the ‘pristineness’ of the environment and thus take away some of the value of visiting one of the last truly wild places on earth.
To control tourism, there are rules and regulations known as ‘General principles of Antarctic Tourism’ which operators from ATS nations must follow. However, those from outside the ATS are unregulated and may be disproportionately harming the environment. The negative effects don’t necessarily outweigh the positives, but policies should be implemented to reduce human impact as more tourists visit the area.
Key drivers (temperature, tourism, fishing) will have a range of negative and positive effects on Antarctic ecosystem services such as the blue carbon pathway, the krill fishing industry and Antarctic tourism. The study suggests that, despite some positive effects of climate drivers, the relative risk level of the Antarctic should be raised from intermediate to high level due to the global importance of the Antarctic ecosystems and predicted future benefits and threats from key drivers.
To read the review this article was about, click here:
To learn more about the Antarctic Treaty, follow this link:
To learn more about Antarctic conservation and to donate to conservation projects, click here: