In our final oceans blog, we visit the end of the world: the ocean surrounding Antarctica.
“Huge blocks of ice, weighing many tons, were lifted into the air and tossed aside as other masses rose beneath them. We were helpless intruders in a strange world, our lives dependent upon the play of grim elementary forces that made a mock of our puny efforts.” ― Ernest Shackleton, South!
The Southern Ocean, which encircles Antarctica, is the fourth largest but “newest” of the planet’s five oceans. It was named by the International Hydrographic Organisation in 2000 and refers to all the waters south of 60°S latitude, including the seas and straits found there. The new definition and the demarcation of the northern border of the ocean have yet to be ratified by all of the IHO’s member states, and some still call it the Antarctic Ocean, if they recognize it as being separate from the Atlantic, Pacific, and Indian oceans at all.
As well as being, literally, polar opposites, the Arctic and Antarctic are very different in a number of ways: Antarctica is composed of bedrock, covered by ice and snow, and surrounded by ocean, and therefore has much lower temperatures and does not fluctuate winter/summer as much as the Arctic, which is mostly frozen water, does. The lowest temperature ever recorded on Earth, -89.6°C, was at Vostok Base near the South Pole. The landscape of Antarctica is still being explored. “The bed of Antarctica is less well known than the surface of Mars…,” said Dr Stewart Jamieson of Durham University in the UK.
Exploring Antarctica gives scientists a picture of very early life on Earth. When it was first formed, the planet had no oxygen. What caused our atmosphere to change so drastically? Bacteria found at the bottom of Lake Fryxell, in the McMurdo Dry Valleys, produce tiny amounts of oxygen, even though they live below the level at which the lake becomes anoxic or without oxygen. It’s possible that these kinds of bacteria, forming green “mats” on the lakebed, echo the producers of the Great Oxidation Event, when the planet’s atmosphere acquired oxygen, millions of years ago.
Antarctica is the only region on Earth that belongs to no one and everyone. Although it appears that at one time the area was temperate, mixed forest, there are no indigenous peoples, and no traces of any, and the region is governed by the 1961 Treaty of the Antarctic, which stipulates that the territory and its resources may be used only for scientific and peaceful purposes. Therefore, although, we know there are mineral deposits and there are probably oil deposits beneath the surface, nobody is allowed to drill for them. At 14 million square kilometres, covered in ice up to the depth of a mile, Antarctica contains 90 per cent of the ice on Earth, and ¾ of our freshwater deposits, but again, they are not accessible to commercial interests. Unfortunately, the Treaty, which in any case expires in 2018, covers only the land mass and not the surrounding ocean. China has announced that it is conducting research into the possibilities of deep-sea mining in the Antarctic. Commercial fishing is also a huge threat to the area and besides the massive krill harvesters, the worst offender for exploiting Antarctic resources is Japan. Despite the 1982 international moratorium on commercial whaling, Japan manages to kill hundreds of whales every year under the guise of “research.” No other country in the world finds it necessary to kill whales to study them. And certainly, those “research subjects,” including more than 150 pregnant cows, should not end up in Japanese restaurants, but they do. Worst of all, despite killing 14, 410 whales since 1982—95 per cent of the whale deaths during the period—Japan has produced only two peer-reviewed research papers on the subject.
The newly formed Swiss Polar Institute has also announced research plans, although its project is more international and environmentally useful: beginning in December 2016, 50 scientists from around the world will undertake the first circumnavigation of Antarctica, monitoring the impact of climate change and pollution in the Southern Ocean.
As with the Arctic, Mount Everest, and other extreme environments on the planet, tourism is increasing in Antarctica. There were 40,000 visitors last year, but cruise ships operate under strict regulations: no heavy fuel, limited numbers of people on shore at any one time, and no landing except at approved sites. The effect of this activity is unknown and must be closely monitored.
A strange phenomenon in Antarctica has been exploited by climate change deniers who claim that it proves our environment is experiencing natural, cyclical changes as opposed to catastrophic events. While we can see the effects of climate change in the western part of the Antarctic continent, where the glaciers and ice shelf are melting into the sea, on the eastern side the ice sheet is actually gaining depth. Why? Scientists say it doesn’t refute the reality of climate change but rather the area is still showing the effects of the last ice age, 12-18,000 years ago. In the low temperatures of the Antarctica, it takes millennia for snow to turn to ice. So, the snow from that time is still becoming ice and therefore increasing the density of the ice shelf. Furthermore, the formation of sea ice is affected by winds and global warming has increased the circumpolar winds. More ice is forming, but it’s thinner and less stable. In the end, insists Bristol University’s Jonathan Bamber, writing in Real Climate, it won’t make a difference: global warming is real and we are seeing its effects everywhere.
There are also a number of theories about exactly why the western Antarctic ice shelf, the ice that extends out from the shore over the water, is melting, including one that says volcanic activity on the ocean floor is warming the water. The ice certainly is being hit from above and underneath: above, the “hole” in the ozone layer allowing more of the sun’s ultraviolet rays to penetrate increases the melt exponentially; below, plumes of warmer water rise from the ocean floor, burrowing into the ice. In the past few decades, seven of the 12 ice shelves in Antarctica have seen crumbling activity. Just last month, a 20km long chunk calved off the Nansen Ice Shelf. We have known for some time that when the ice sheet melts entirely, projected to occur around 2500 at the current melt rate, the sea level on Earth will rise by 12 feet or more. It had been assumed that the rate of melting would be very slow, but now it seems that by 2100, the seas could rise by at least three feet. Studying past ice ages, American scientists Robert DeConto and David Pollard are working to predict the rate of collapse of Antarctic ice, and their results are very frightening. Because of human settlement patterns, many large cities are on or near the coast or tidal rivers: New York, London, Venice, Shanghai, and Sydney would all be threatened by higher water levels.
There is some good news, however: models suggest that the ice will survive if current greenhouse gas emission targets—to limit temperature rise to no more than 2°C—are met. The Paris conference in December 2015 produced an agreement to reduce emissions from coal-fired power plants, supported by enthusiastic polluters like China, India, and the USA. Unfortunately, in February 2016, the US Supreme Court found in favour of 27 coal-producing states and agreed to halt the Clean Power Plan temporarily. Donald Trump, the Republican nominee for US President, says he “doesn’t believe” in climate change and has promised that if he is elected he will re-open coal mines instead of supporting alternative, clean energy sources. Both Hilary Clinton and Bernie Sanders have comprehensive environmental plans as part of their platforms.
The last word on Antarctica should belong to Roald Amundsen, the first man to reach the South Pole, and the North Pole and to traverse the Northwest Passage. He beat Ernest Shackleton to the South Pole by one month. Amundsen said, "The land looks like a fairytale," but he also summed up why his expedition succeeded and others failed: "Adventure is just bad planning."