Antarctica the unknown
Dr Anjani Ganase discusses the most extreme environment on earth, the unknown continent, which has been positioned by the international community as a place of conservation, collaboration and human accord.
Extreme environment
When learning about the seventh continent, Antarctica, it’s hard to really understand how alien this landscape is. On google maps, there’s nothing but a blank white visual. This is the coldest, driest and highest place on earth. Antarctica is covered in ice – in some locations five kilometres deep. It is a place that continues to defy human civilization, ancient and modern.
Antarctica has some of the lowest temperatures ever recorded – -89.2 C the lowest ever recorded on earth at Vostok Station. Geographically, Antarctica is two parts, East and West Antarctica divided along the Transantarctic mountains with eastern and western faces controlling the flow of ice sheets, either east or west. Mount Kirkpatrick is the highest mountain on the continent towering 4,528 m (Mt Everest is 8,848 m) in the Queen Alexandra Range. East Antarctica is much larger than West Antarctica with thicker ice sheets and higher elevations. The Antarctica Peninsula extends north from west Antarctica towards South America. Antarctica is surrounded by the Southern Ocean that whips around the continent. During the winter, sea ice forms and adds 19 million square-kilometres (records from 1981 – 2020) more than doubling the area (13.66 million squared-kilometres). During the summer the sea ice recedes to about three million km2. Within the Antarctic circle, you can experience 24 hours of daylight for several months in the summer, but there’s the same total (24 hours) darkness in the winter.
Antarctic landscape. Credit: Jeff Hester / Ocean Image Bank
Antarctic wildlife
Life in the cold is mastered by only a handful of creatures. With no terrestrial wildlife, Antarctica is home to marine mammals that divide their time between foraging the relatively warmer oceans and coastal areas of the icy continent. Eighteen species of penguins are the only birds. The Antarctic food web is founded in the ocean. Phytoplankton are fed upon by krill (zooplankton) which are consumed by fish. The fish and the krill are the main source of food for most of the marine animals, penguins, seals, whales, and elephant seals. Leopard seals also hunt seals and penguins. The top carnivore is the killer whale that preys on all the marine mammals. Research on the wildlife is focused on estimating populations, and studying the adaptations to the environment, such as the diving physiology of penguins. Innovative ways have been devised to track Emperor penguins for example: satellite imagery of their colonies shows up as reddish-brown poo stains on the sea ice. From the stained areas, colony size may be estimated.
Research on what is hidden beneath the ice sheets reveals the long history and ecology of Antarctica. About a third of Antarctica’s continental shelf seabed sits below a layer of ice. For a study in 2021 by the British Antarctic Survey, cores were drilled 900 m through the ice shelf to access the seabed below. The drop cameras revealed an array of marine organisms living on top of submerged rocks. Many of the organisms were unidentifiable but there were species of filter feeding marine sponges. What they were feeding on, however, stumped the scientists as there was no discernible food source nearby and an up current photosynthetic food source over 600 km away (Griffiths et al 2021).
Leopard Seal. Credit: Jeff Hester / Ocean Image Bank
Climate change research
Antarctica Is home to about 5,000 human residents during the summer but only 1,000 during the cold dark winters. Most of these residents work at research stations, of which there are about 82. Many of the stations are located along the Antarctic Peninsula. Research covers biology, geology, and the complex science of climate change. While long-term trends in the seasonal changes in the extent of sea ice are not showing the severe declines we see in the Arctic. On the land, Antarctica is losing ice mass at increasing rates because of ice loss from the ice shelves that collapse into the ocean to form icebergs. While ice mass is being lost in both east and west Antarctica, the loss is greater in west Antarctica because of the warm ocean undermining the glacier in low-lying coastal areas. More specifically, the Antarctic Peninsula in west Antarctica is experiencing warming at a rapid and severe rate. Here, the air temperature has increased by at least four degrees between 1958 and 2010, making the Peninsula the most rapidly warming place on earth. In contrast, east Antarctica temperatures only rose by an average of 0.1 degree for the same period. The ecological consequences in places of rapid temperature rise includes the decline in the krill populations and changes in the locations of penguin colonies as the sea ice distribution changes.
Political and scientific collaboration
Antarctica is governed by 30 countries who signed on to the Antarctic Treaty initiated in 1959 by 12 countries. The treaty is made up of 14 articles that include: (1) Antarctica will be used only for peaceful purposes; (2) Freedom of scientific investigation in Antarctica and cooperation toward that end…; (3) Scientific observations and results from Antarctica shall be exchanged and made freely available. Article 4 dictates that while the Treaty is in force, no activities shall constitute a basis for asserting, supporting or denying a claim to territorial sovereignty in Antarctica or create any rights of sovereignty in Antarctica. Essentially, Antarctica is meant to be a hub of research and international scientific collaboration for all.
Signatories to the Treaty must follow the protocol for environmental conservation and the protection of flora and fauna. This includes no harm to wildlife (permitted situations usually associated with scientific research); and avoiding the introduction of non-native species. Antarctica is designated a shared space for science and conservation and a suitable setting for collaborating on the pressing issues that affect the health of our planet. Antarctica regulates global climate systems and drives global ocean circulation that connects the Caribbean Sea and the Southern Ocean.
Later this year, I join a group of international women scientists journeying to Antarctica on a voyage of discovery, research, networking, and training as part of the Homeward Bound leadership programme. On expedition, professionals in the fields of Science, Technology, Engineering, Math, and Medicine (STEMM) will discuss and develop projects to combat major issues of climate change impacting communities and environments in their home countries and around the world. As I proceed on this journey, I promise to share my experiences and findings.
We will be exposed to the most extreme and harsh environment and challenged to collaborate for the benefit of the planet. If it can be done in Antarctica, it can be done anywhere.
Signy Island Antarctica base at dusk. Photo courtesy
www.coolantarctica.com
References
Griffiths, Huw J., et al. "Breaking all the rules: the first recorded hard substrate sessile benthic community far beneath an Antarctic ice shelf." Frontiers in Marine Science (2021): 76.
https://discoveringantarctica.org.uk/challenges/sustainability/impacts-of-climate-change/
https://www.antarctica.gov.au/about-antarctica/geography-and-geology/geography/maps/
Understanding climate: Antarctica sea ice extent - https://www.climate.gov/news-features/understanding-climate/understanding-climate-antarctic-sea-ice-extent#:~:text=Historically%2C%20Antarctic%20sea%20ice%20has,million%20square%20miles)%20in%20summer.
Secretariat of Antarctica Treaty - https://www.ats.aq/index_e.html
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