Climate change in the Arctic

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The Arctic is the health barometer of the world and we, the Inuit, are the mercury of that barometer. As goes the Arctic, so goes the world.
Sheila Watt-Cloutier, Nobel Peace Prize Nominee, Inuk activist, Canada

In the summer of 2014 Nera Cornell, 15, sailed to the High Arctic onboard the yacht Aventura as part of the Blue Planet Odyssey. Read her reports here.

The opening of the Northwest Passage is among the most conspicuous results of global warming and average temperatures in the Arctic region are rising twice as fast as they are elsewhere in the world.

The Arctic icecap has been retreating at an increasingly accelerating pace as air and sea temperatures rise. According to NOAA (National Oceanic and Atmospheric Administration), in the summer of 2012 the Arctic sea ice dipped to its smallest extent ever recorded in more than three decades of satellite measurements. For 2013, and it seems 2014, Arctic ice remains consistently below its average 1981 to 2010 extent.

The melting of the Arctic ice cap due to warmer air and sea temperatures, is a simple fact. The consequences, though, are complex and far-reaching – not only for the Arctic itself, but for the entire planet.

The scale and complexity of the problem are only now becoming clear and there is still much to learn. Some of these effects will take place within our lifetime, others will occur over hundreds, and even thousands of years.

A brief description of ice

The Arctic is not a continent, but an ocean, whose waters mostly remain frozen all year round. It forms part of the “cryosphere” which describes those parts of the Earth’s surface where water is in solid form as ice, snow, and frozen ground such as permafrost.

On land

The ice locked into glaciers and ice sheets on the land has been formed by snow and rain accumulating over thousands of years. Greenland holds 10% of the world’s ice, and is the second largest ice sheet in the world, after Antarctica.

As the glacier moves by gravity slowly towards the edge of the land, pieces break off, or calve, on the coastline and these float off as icebergs.

The ice in an iceberg might be hundreds or thousands of years old, and the older it is the bluer it becomes.

Icebergs are beautiful, but dangerous to shipping, because only about one seventh of their mass can be seen above water, and also, melting can make them very unstable and liable to capsize without warning.

Sea-ice

The other type of ice to be encountered in the North West Passage is sea-ice, created when the sea freezes over during the winter. Some sea ice is young, only a year old. The older sea-ice, which has survived more summers, is less salty, as the salt leaches out into the sea, and that makes it harder also. In the past, the winter ice pack in the Arctic was mainly composed of multi-year, very thick ice, as you can read in the descriptions of historic expeditions. Today, very little old ice remains.

This animation by NOAA climate.gov shows maps of sea ice age from 1987 – 2013.
Age class 1 means “first-year ice,” which is ice that formed in the most recent winter.
The oldest ice (9+) is more than 9 years old.

Melting Ice

Extent of Arctic sea ice May 2014 (from the U.S. National Snow and Ice Data Center)

The melting and freezing of sea ice is a natural part of life in the Arctic. At the end of the short summer season, September marks the minimum extent of the sea ice, and through the long winter the sea ice builds up again, reaching its maximum in March.

Since the satellite record began in 1979, there has been an 11% decline in September ice extent. It does vary year on year, but the trend is always downward. Scientists predict that at some point the Arctic Ocean will be completely ice-free in summer.

What does this mean?

The lack of sea ice threatens species such as polar bears and ringed seals who have evolved to depend on the ice to live, breed and hunt. It also affects local populations, challenging the age-old way of life for the Inuit.

Less sea ice also increases coastal erosion, threatening local communities that live by the sea and making them more vulnerable to bad weather.

Reaching a tipping-point?

If all the water currently locked in ice sheets around the world melted, the seas would rise by up to 70 meters. Most of this ice is in Antarctica and Greenland. Recent evidence from satellite imagery shows that global warming is accelerating the melt, and some giant glaciers are reaching the point of no return.

Amplifying Global Warming

White snow and ice reflect the sun’s heat away from the planet, in what is known as the albedo effect. As the area of land and sea in the Arctic covered by snow and ice diminishes, the darker sea and land absorbs more heat.

Forest fires, another side effect from global warming, send soot into the atmosphere, much of it landing on Greenland snow. This further darkens the snow.

All of this contributes even more to the warming of the planet, in a process scientists are now calling Arctic Amplification.

What about the weather?

Less sea ice also affects polar weather, as it disrupts the seasonal heat exchange between the Arctic Ocean and atmosphere. Less sea ice may also be having an effect on the jet stream, which in turn affects weather patterns around the world.

Scientists are only now beginning to understand this complex interplay between sea ice coverage, ocean and air temperatures, air pressure, jet streams, and weather in other parts of the world.

Thawing Permafrost

Permafrost refers to ground or soil which has been frozen for at least two years. Some permafrost is hundreds of metres deep and has taken thousands of years to form. Thawing of the Arctic permafrost releases methane, and other hydrocarbons, which are all greenhouse gases. Methane is 72 times more potent as a greenhouse gas than carbon dioxide.

The thawing of permafrost can also result in erosion, causing further damage to the soil. It weakens the foundations of buildings constructed on frozen ground and threatens coastal settlements. As the ground thaws, vegetation starts to decay, releasing even more methane and CO2.

Ocean Acidification

The Arctic Ocean is more vulnerable to ocean acidification, as the seas absorb the excess carbon in the atmosphere. Accelerating ice melt and ocean warming further increase acidification.

The Arctic supports a rich array of wildlife which relies on food webs that begin at the tiniest level with plankton and other invertebrates. If acidification affects them adversely, the entire eco-system is threatened, which in turn is a threat to all Arctic life, animal and human, that relies on the sea for food.

Arctic Ecosystem (from Caff.is – Conservation of Arctic Flora and Fauna)

Other threats to the Arctic

Pollution

Less sea ice making the Arctic more accessible to shipping has had the effect that oil companies want to come and tap the large oil reserves in the Arctic Sea. The question as to how an oil spill could be cleaned up in the harsh environment remains unanswered.

Arctic Haze

The Arctic is imagined by most to be a pure, unpolluted part of the world – one of the last wildernesses left on earth. In fact, since the 18th century people have observed how every fall and winter a dirty reddish-brown smog appears in the Arctic. In the 1950s it was dubbed the Arctic Haze. Its origins were mysterious until studies in the 1970s showed it to be man-made, not natural.

The haze consists mainly of sulphur and nitrogen compounds, some of it natural (like sea salt, ash from forest fires, soil dust blown on the wind) but also airborne toxins like herbicides and pesticides, heavy metals and industrial organic compounds. Prevailing winds and ocean currents means that pollution from other parts of the world, from Europe, Asia and America, migrates north.

Studies have shown that these toxins exist in particularly high levels amongst the Inuit population, and large predators like the polar bear, which are at the top of the food chain.

Their diet consists of marine life such as whales, walruses and seals that have accumulated high levels of man-made toxins from pesticides and other chemicals.

Plastic

Recent studies have shown that tiny particles and plastic and other man-made materials are trapped in the ice; as this melts further, it will release these back into the oceans.

Scientific Research in the Northwest Passage

Jimmy Cornell’s Aventura launched 2 oceanographic buoys on behalf of Meteo France, one south and the other west of Greenland.

In the summer of 2014 Blue Planet Odyssey yachts carried out the following research in the seas around Greenland and Arctic Canada:

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