coastal erosion

Qikiqtaryuk: the Big Island by Sam Cornish

Qikiqtaryuk - the transliterated name in Siglitun Dialect of Inuvialuktun for Canada’s westernmost Arctic island. It means: the Big Island. But the Big Island is getting smaller.

The northwestern corner of Qikitaryuk, sunlit sea ice beyond

The northwestern corner of Qikitaryuk, sunlit sea ice beyond

Large thaw slumps work their way slowly back into the interior of the island

Large thaw slumps work their way slowly back into the interior of the island

The narrative of this island is unusual. It was borne from the advance of ice, and is ultimately being destroyed by loss of ice. It has a human story - which in this post I’ll give background to with a rough intro to the changing people of the Arctic through the last few millennia. I’ll explain why the shape of the seafloor near to this island made it a great place to hunt - and live. I’ll also talk about what happened when whalemen from San Francisco started to overwinter at the island over a hundred years ago. All photos are my own, taken when I visited the island in July 2015. This blog post is informed by the excellent book, Herschel Island - Qikiqtaryuk, edited by Chris Burn. The book covers everything from climate to culture and answers the implicit request of Danny Gordon who, along with his family before him has seen scientists and archeologists come to Herschel for decades: ‘I am supportive of research as long as it is properly explained’. Danny’s sentiment is important not just in the context of conducting research on lands used by First Nations or indigenous communities, but also as a wider message to the world of research science, in which the norm is to only explain research to other scientists.

A bear skin dries in the summer air

A bear skin dries in the summer air

The origins of the island take us back to the mountains I looked at in the last post. Between 200 - 100 million years ago, rifting of the Earth’s crust north of where the British Mountains now lie opened up the Beaufort and Mackenzie sedimentary basins. As the British mountains underwent a new period of construction c. 75 Myr ago, rivers such as the Firth incised into the mountain belt and carried sediment downstream, to be deposited in these basins. As more and more sediment piled up on the continental slope of NW Canada, sediments nearer the bottom of the pile cemented into rock under pressure. Now, the top of the sediment pile - deposited and reworked by rivers, glaciers and the sea - is unconsolidated to a depth of approximately 1 km, and several kilometres of older cemented sediments lie below that. This is basically a big recycling process; the rocks that constituted the mountains - the fragments of which are now creating these new rocks - had themselves been formed from the tiny fragments of mountains washed into a shallow sea and then uplifted by tectonic convergence. And some time in the geological future the new rocks may be crunched into mountains.

The Firth spreads into a braided river upon reaching the coastal slope, where it continues to deposit sediment from the British Mountains, as it has been doing for tens of millions of years

The Firth spreads into a braided river upon reaching the coastal slope, where it continues to deposit sediment from the British Mountains, as it has been doing for tens of millions of years

At some time during the last glacial period, all traces of which had ended by 10,000 years ago, an ice sheet advancing along the northern coast of NW Canada gouged deep into this unconsolidated sediment in the coastal plain. Qikiqtaryuk was made as a sheet of sediments several hundred metres was shunted along a plane of failure up and out onto the surrounding land. The close match in size between the island and a corresponding basin (Herschel Basin) directly to its east is evidence for this genesis, as is the deformed glacier ice that can be seen exposed in the coastal bluffs on Qikiqtaryuk. Furthermore, a special explanation is required for significant topography that is formed solely of unconsolidated material, which is made of sediment that pools in basins - it does not collect into high plateaux that project above the surrounding surfaces.

As the climate warmed into the Holocene epoch - the time of relatively stable warm temperatures 10,000 yrs ago to the present - the sea level rose, and continues to rise, currently c. 100 m higher than at the glacial peak. When humans first visited Qikiqtaryuk, it would very likely have still been a peninsula.

Professor Chris Burn explains the existence of sand and gravel bars between Qikiqtaryuk and the mainland on the approach to the island

Professor Chris Burn explains the existence of sand and gravel bars between Qikiqtaryuk and the mainland on the approach to the island

The first known inhabitants of Arctic Canada and Greenland are often lumped into a broad cultural entity: the Arctic Small Tool tradition. This culture developed in parts of western Alaska around 4,500 years ago and used microblade technology - small blades made from rocks like chert or obsidian which break into sharp flakes. Microblades helped to improve hunting success for these people who often had to move significant distances when faced with food scarcity. Interestingly, the bow-and-arrow technology of the Arctic Small Tool tradition in Arctic Canada was not used by the next major group to dominate, the Dorset Culture, who instead primarily hunted seals using triangular end-blades hafted onto harpoons. The Dorset Culture, inscribed in Inuit legend as being gentle giants with shamanistic traditions and otherworldly carvings of Polar Bears, were almost entirely extinct by 1500 AD, and rapidly replaced by the ancestors of the modern Inuit and Inuvialuit, the Thule. The Thule achieved a rapid spread across Arctic Canada to Greenland in the centuries 1100-1400 AD, and skin-covered boats entered the Arctic archaeological record for the first time. The Thule are frequently characterised as intelligent toolmakers who were using iron before European contact. Unlike the Dorset Culture, there is little evidence for an emphasis on the supernatural within the Classic Thule.

Qikiqtaryuk was probably semi-permanently occupied since the advance of the Thule around 1200 AD; the longest record of inhabitation by the Inuvialuit and their ancestors in the Western Arctic. Multiple archeological sites on the island reveal how these people lived and hunted. There is, of course, so much to the history of these people - language, relations, behaviour - that I’m neglecting here.

Avadlek Spit - archeological study has uncovered a community from 1500 AD who constructed a home on this strip of land

Avadlek Spit - archeological study has uncovered a community from 1500 AD who constructed a home on this strip of land

It is the special physical and oceanographic setting of Qikiqtaryuk that has made it a desirable place to live, the Big Island.

Qikiqtaryuk lies next to the junction of two large portions of continental shelf to the east and west. At the juncture is the Mackenzie Trough, a submarine valley running down to the ocean depths. During the ice-free season, easterly winds across this part of the Arctic coast dominate. Due to the fact that we are on a spinning planet, the surface water that gains momentum from these winds actually moves to the right-hand side of the winds in the northern hemisphere, and to the left in the southern hemisphere. This is called the Coriolis Effect. As the surface water moves to the right of the easterly winds, away from the coast, water must replace it from below. The Mackenzie Trough provides a conduit for these waters to come from the nutrient-rich deep ocean. This influx of nutrients leads to plentiful growth of tiny plants in the surface waters called phytoplankton, which are then fed on by tiny animals called zooplankton. The upwelling current sweeps these zooplankton onto the shelf in an appetising brew for the Arctic’s largest mammal, the Bowhead Whale. The Bowhead has the largest mouth of any animal on Earth, and uses its enormous head to break through sea-ice up to 60 cm thick for air. Seals - and therefore polar bear - also have historically thrived at Qikiqtaryuk.

The Mackenzie River discharges 600 cubic km of freshwater each year into the Arctic Ocean. Qikiqtaryuk lies close to the Mackenzie Delta, and receives a brackish river plume that in the summer can be as warm as 16 C. The river is fed by two major lakes - the Great Slave and Great Bear lakes - meaning that in the winter, discharge continues, and freshwater moves out beneath the ice-covered ocean. Relatively buoyant due to its low salinity, it spreads out at the top of the water column below the land-fast sea ice. At the juncture between land-fast and open-water sea ice, collision of the two domains results in a jumbled pile of ice, protruding above and below the surface. This subsurface rubble acts as a barrier to the spread of freshwater, and the river plume slowly accumulates into a freshwater lake below the ice. Known as Lake Herlinveaux, by the end of winter it is supposedly the 20th largest lake in the world.

The relatively fresh water around Qikiqtaryuk provides a migration channel for freshwater fish swimming between the Alaskan Colville River to the East and the Mackenzie to the West. Fish such as the Arctic Cisco and Dolly Varden Char use the shallow channel of open water between Qikiqtaryuk and the mainland, known as Workboat Passage. This patch of water is sheltered by gravel bars at either end, and is a habitat for birds and sea-ducks. The gravel and sand bars are all that remain of an earlier shoreline, the more easily eroded land behind the gravel beaches degraded and washed away by rising sea levels.

Five-hundred year old remains from a house on the Avadlek Spit, which projects into Workboat Passage, indicate its inhabitants hunted perhaps entirely fish and birds, and stored food for the winter in a log-lined cache. Such a low reliance on seal is thought to be unique for a coastal site in the Western Arctic.

 

Tundra polygons meet the decaying coastline, where plumes of sediment are visible entering the ocean

Tundra polygons meet the decaying coastline, where plumes of sediment are visible entering the ocean

By the time John Franklin arrived at Qikiqtaryuk in the summer of 1826, the people of Qikiqtaryuk had already taken their place in a two-way passage of trade. Iron, tobacco and beads headed east, while skins and furs from the Mackenzie Delta were taken west by a series of aboriginal traders to northeastern-most Asia, where Russians took the goods onwards to markets in China and Europe. There is no record of Franklin recognising an indigenous name for the island; instead he gave it the name Herschel Island. The Herschels were a family that emigrated from Germany to the UK as musicians, and achieved fame as the foremost astronomers of their time. Herschel Island is the name dominantly used today.

It was soon realised that the sheltered waters of Pauline Cove provided protection against the movements of ice that could crush overwintering ships like tin cans. Once the whalemen fleets arrived at Qikiqtaryuk - overwintering at the island from 1890 to 1912 - lifestyle changed rapidly for the indigenous populations. In interactions that spanned the spectrum from joyful to disastrous, the whalemen brought material goods, baseball, 4th July obstacle races, alcohol, buildings, gonorrhoea, syphillis, dances, theatre, and infections such as measles, influenza, typhus and tuberculosis. Soon after the establishment of regular whaling around Qikiqtaryuk, a mission was established, as well as a school, health clinic, and police outpost. Ultimately many Inuvialuit converted to Christianity. In 1909, the Bishop of Yukon oversaw the first legal marriage of a white man and an Inuit woman in the Canadian Arctic. The previous year, the price of whalebone collapsed, and fur trading took on a greater importance at Qikiqtaryuk. The influence of the missionaries is of course controversial, even though they may have seen themselves as providing an antidote to some of the damaging effects of the new cultural connections (disease, prostitution, alcohol abuse). Trading vessels visited Qikiqtaryuk each year until 1936, when Aklavik assumed the mantle of the region's trading centre.

Today the island is a Territorial Park, co-managed with the Inuvialuit. It remains a place for traditional harvesting of Arctic animals, but is also a base for the scientific investigation. Scientists interested in Arctic ecosystem dynamics can perform surveys of its biodiversity, while permafrost scientists can study changes in ground temperatures and the decay of the coastal bluffs.

Scientists and park rangers meet at Pauline Cove

Scientists and park rangers meet at Pauline Cove

Professor Chris Burn and Parks Canada Ranger Jay Frandsen take temperature readings of the permafrost ground

Professor Chris Burn and Parks Canada Ranger Jay Frandsen take temperature readings of the permafrost ground

It’s cold at Qikiqtaryuk; the annual mean temperature over the last decade has been -9 C. However, Qikiqtaryuk is one of the most striking examples of a place affected by anthropogenic climate change. Annual mean air temperatures since 1995 are 3 C higher than recorded in the years 1899-1903, the annual freeze-up of the ocean around Qikiqtaryuk now occurs nearly an entire month later than documented by the whalemen in the 1890s, and the temperature profile of the ground - decreasing to a depth of c. 50 m - shows a warming signal gradually diffusing downwards into the permafrost ground.

Thawing of the ice that binds the permafrost with warming temperatures is leading to dramatic degradation of the ground, most spectacularly seen on the coast. As the ice that binds the sediment thaws, the ground can collapse into a slurry, and expose a new face of permafrost ground that can then thaw, collapse, and so on. These features are known as retrogressive thaw slumps, and their total area increased by 160% between 1952 and 2000. Such an ice-rich coastline is vulnerable to thermal and mechanical erosion by waves, and the island currently experiences a stunning average erosion rate of half a metre per year, highest in the northwest where the coastal bluffs face storm-surge waves head-on. Rising sea levels and a shorter ice-protected season are likely to increase the rates of coastal erosion and thaw slumping.

Deformed glacier ice revealed in the headwall of a thaw slump, slurry draining towards the sea below

Deformed glacier ice revealed in the headwall of a thaw slump, slurry draining towards the sea below

Thaw slump, with grizzly bear for scale (look in the top right corner)

Thaw slump, with grizzly bear for scale (look in the top right corner)

In summer, walking over the green tundra, spotted with wildflowers and bog cotton, Qikiqtaryuk’s inextricable relationship with ice is not immediately obvious. But it is an island created by the advance of ice in a colder climate, its ground is bound by ice, and its coastline sheltered by sea ice in winter from waves. Its very existence is made less stable by warming temperatures.

By fortune of its placement next to the Mackenzie Trough and Mackenzie River, it became a hotspot for whales, fish, birds and bears - and therefore humans. Qikiqtaryuk has witnessed profound cultural changes. But now changes brought about by humans are, via the climate, causing profound physical changes to the island. It is also another example of where indigenous people and practices are on the front lines of climate change.