Talk at Field Naturalist’s Club of Ballarat on 3 June 2011
Carol’s interest in the geography of polar regions began when she was a form 6 student. Since then she has visited the Antarctic, and she spoke to the Club about her 2010 Arctic trip to Svalbard and Greenland. The Aurora Expeditions tour began at Longyearbyen when she boarded the Polar Pioneer, a 71m, 2000 tonne ship which is ice-strengthened but not an ice-breaker. It can move through loose pack ice.
With the aid of maps Carol outlined the route of her trip and explained that climate is affected by latitude and ocean currents. Warmth from the North Atlantic Drift of the Gulf Stream results in a lack of ice on the west coast of Svalbard while cooler currents mean that the east side has sea ice in the winter. Evidence of global warming is clearly seen in the Arctic. The extent of sea ice has shrunk from the 1979-2000 median coverage. 2007 was the year of least summer sea ice and 2010 had the least winter ice. The Greenland Sea ice is declining by 10% per year. Some consequences of global warming in the Arctic are that it is possible for shipping (oil tankers) to operate further north for longer periods. There are border disputes between countries over areas of sea bed and the oil resource they contain.
The Svalbard Archipelago is a group of islands now under Norwegian sovereignty. The main island is Spitsbergen, The main settlement is the town of Longyearbyen (until recently a company town, now under civil government), population 2000 (made of workers who live in rented houses; when no longer working people must return to the Norwegian mainland). Svalbard Archipelago had no native people. It was discovered in 1596 by Dutch explorer Barents. The archipelago has been used as a whaling base and for coal mining. In modern times research stations have been established by several countries investigating glaciology, climate change and atmospheric physics. Tourism is increasing in importance. Around town are signs warning of the danger of Polar Bears. Out of town people must carry a rifle.
A male Polar Bear was seen feeding on the carcass of a fin whale which had died the previous summer and been deep frozen over winter. The vertebrae could be seen above the water; bears had to retrieve flesh and baleen from under the water to feed. Polar Bears are solitary animals except in the mating season. Females with cubs are reluctant to approach males because the males will attack and kill cubs. Polar Bears are well adapted to live in a cold environment with black skin to absorb heat, although most of the body, including the soles of the feet, are covered with fur. A layer of blubber also insulates from the cold. Polar Bears are more likely to suffer from heat than cold.
Global warming threatens Polar Bears; as the amount of sea ice decreases, the Polar Bears are forced more onto land where they become scavengers on tips and come into contact with humans. Another threat is Persistent Organic Pollutants which become concentrated in Polar Bears at the top of the food chain. Polar Bears mate in summer, and have delayed embryo implantation. In November the female digs a den in deep snow and the naked young, about the size of a guinea pig, are born in December. The female must lift the cubs off the ice onto her thighs to nurse them. They leave the den in March-April and stay with the female for 2-3 years learning how to hunt. Polar Bears can live about 16-20 years in the wild. There are 2,500-3,000 bears in the Svalbard Barents Sea region, and 25,000-25,000 in the Arctic as a whole.
Brunnich’s Guillemots nest on dolerite cliffs. Guano produced ensures lush green gowth at the base of the cliffs where Arctic Foxes wait for any young which crash land when making their first flight to the sea. When the fledgling lands in the ocean, the male parent cares for the chick. Few Puffins were seen because the breeding season was nearly finished.
Tundra is covered with low vegetation – dwarf birch and willow reach a height of 10 cm. There is little bare ground. “Reindeer moss”, actually a lichen, covers big areas. Flowering plants have a 3 month period to grow, flower and set seed. Snow Buttercup had yellow flowers and Moss Campion purple flowers. They have adaptions to reduce transpiration because liquid water is often in short supply. Under the tundra permafrost is up to 1500m deep; the top 0.5m melts in summer. Global warming which is melting permafrost is causing problems to the stability of buildings and roads. It is also releasing methane (a potent greenhouse gas) from decaying vegetation.
Svalbard Reindeer scratch through snow in the winter to feed on vegetation.
Heaps of whale bones are a remnant of the whaling industry. Bowhead and Beluga whales were hunted. Beluga whale skin is the only whale skin that can be tanned to make leather.
Carol’s images of glaciers were spectacular. At the foot ot retreating glaciers are moraines – the rock ground up by moving ice. Glacier ice is white due to air bubbles that scatter light. Monacobreen Glacier has a 4km frontage at sea level. Glaciers are moving faster due to global warming. The melt water acts as a lubricant causing a surge and icebergs calve off. Ice cliffs were up to 300 feet high making people in Zodiacs appear very small. When it is quiet you can hear a glassy tinkling as air escapes from the floating, melting blocks of ice.
Some birds such Ivory Gull and Black Guillemot are ice specialists which hunt at the edge of the ice. Kittiwakes are the most numerous gull. Arctic Terns nest in scrapes on the ground and dive-bomb unsuspecting toursts! They are migratory and travel over 20,000km to the Antarctic in the southern summer.
Walruses laze about in large groups. The stench is very strong if you are down wind! They feed by sucking the flesh from crustaceans on the sea floor. Their long tusks are not used for feeding but for fighting and to haul themselves onto ice shelves.
Carol showed us the midnight sun; at 80oN the sun does not set in July.
From Svalbard the tour crossed the Greenland Sea and cruised down the east side of Greenland. South of about 75oN there is no pack ice in summer, so they were able to enter fjords; the weather was sunny with no wind. Icebergs form a range of interesting shapes by melting and tilting, some look like castles complete with turrets and windows. A female Polar Bear with 2 cubs approached the ship over loose pack ice, probably attracted by the smell of cooking as well as natural curiosity.
Musk Oxen have a misleading name – they do not smell like musk and are related to sheep and goats. They have a thick, double coat. The inner coat is collected and used to make (expensive) garments. The Arctic Fox was seen in its grey summer coat. Arctic Hares remain white year round. Butterflies and Bumble Bees were also seen among the vegetation. Eider Ducks were common. The female plucks down from her breast when preparing a nest and some of this is harvested for warm bed covers.
Ittoqqortoomiitt is a town of 500 people on the east coast of Greenland, established in 1925 where hunting would be more successful. Houses are built on bare rock with pipes lying on the surface.The population still uses traditional subsistence methods of fishing and hunting for food and some clothing – but there is also a supermarket! Dog teams are used to hunt Polar Bears and seals in the winter, but skidoos and boats with outboard engines are just as likely to be used. As a former Danish colony now self-governed by the Inuit (except for defence), Greenland still benefits from subsidies and has high standards of community facilities.
A Zodiac cruise in the fjords leading into Scoresbysund revealed interesting geological structures; for example, Red Island is formed from Devonian sandstone. Basalt intrusions solidified to form dykes. This harder rock forms structures when the softer sandstone is eroded. Because little soil forms in this climate, the layers of the sedimentary rocks are visible so tilted strata and even whole folds such as anticlines are visible.
Carol’s voyage finished by crossing the Denmark Strait and docking in Iceland where she undertook a tour which frequently went off the beaten track – but that’s another story!