Sunday 14 November 2021

Climate change threatening Canada’s permafrost

Global News in Canada shows that here’s another piece to the climate change puzzle that Canadians must confront. 
Few countries in the world have permafrost, but Canada has 4 million square kilometres of it.
Warmer temperatures in the Arctic are thawing permafrost -  which accounts for 40 per cent of this country’s surface.
That big melt is releasing carbon that has been locked away for centuries. Not only that - life is being disrupted in these remote northern communities. Eric Sorensen explains more.

Permafrost is defined as ground that continuously remains below 0 °C (32 °F) for 2 or more years, located on land or under the ocean. Permafrost does not have to be the first layer that is on the ground. It can be from an inch to several miles deep under the Earth's surface. Some of the most common permafrost locations are in the Northern Hemisphere. Around 15% of the Northern Hemisphere or 11% of the global surface is underlain by permafrost, including substantial areas of Alaska, Greenland, Canada and Siberia. It can also be located on mountaintops in the Southern Hemisphere and beneath ice-free areas in the Antarctic. Permafrost frequently occurs in ground ice, but it can also be present in non-porous bedrock. Permafrost really is certainly formed from ice holding various types of soil, sand, and rock in combination.

Permafrost frequently contains large amounts of so-called biomass and decomposed biomass that has been stored as methane and carbon dioxide in the permafrost, making the tundra soil a carbon sink. As global warming heats the ecosystem and causes soil thawing, the permafrost carbon cycle accelerates and releases much of these so-called soil-contained greenhouse gases into the atmosphere, creating a feedback cycle that increases climate change.

"Biomass" is plant or animal material (sometimes used as fuel to produce electricity or heat). Examples are wood, energy crops, and waste from forests, yards, or farms. Since biomass technically can be used as a fuel directly (e.g. wood logs), some people use the terms biomass and biofuel interchangeably. More often than not, the word biomass simply denotes the biological raw material the fuel is made of. The word biofuel is usually reserved for liquid or gaseous fuels, used for transportation. The USA Energy Information Administration (EIA) follows this naming practice. The IPCC (Intergovernmental Panel on Climate Change) defines bioenergy as a so-called renewable form of energy. In 2017 the IEA (International Energy Agency) described bioenergy as really the most important source of renewable energy.

The International Permafrost Association (IPA), founded in 1983, has as its objectives to foster the sharing of knowledge concerning permafrost and to promote cooperation among persons and national or international organisations engaged in scientific investigation and engineering work related to permafrost and seasonally frozen ground. The IPA became an Affiliated Organisation of the International Union of Geological Sciences in July 1989.

The Association’s primary responsibilities are to convene International Permafrost Conferences, undertake special projects such as preparing databases, maps, bibliographies, and glossaries, and coordinate international field programmes and networks. The International Conference On Permafrost (ICOP) is regularly held since 1965.

Permafrost or perennially frozen ground is defined as earth material that remains at or below 0 °C for at least 2 consecutive years. As such, upwards of 25% of Planet Earth is underlain to some degree by permafrost and in extreme conditions reaches depths of 1500 meters. Permafrost occurs in the high latitudes and mountains and plateaus of both hemispheres.

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