4a. The Canadian Arctic: Geography, ecology, people and climate
The Arctic is often defined using political, climatic, biological zoning and varies greatly amongst Arctic nations. Using geophysical definition as the land and sea, north of the Arctic Circle and which experiences polar day from April to September, and polar night from October to February. Overall, Arctic climate varies greatly by location with annual mean surface temperatures of 4C in Reykjavic Iceland, to -28 C at the crest of the Greenland Ice Sheet. Even within Canada there is much variation and the vastness of the Arctic make it difficult to generalize about its climate but some trends are observable. Overall, the three coldest months are January to March and are often considered …show more content…
Large rivers connecting the interior to the Arctic Ocean and smaller tundra streams transport heat, water, nutrients, contaminants, sediment, and biota and greatly affect the regional environments. There are permanent standing waters of various sizes that include small, shallow tundra ponds, and larger, deeper water bodies. Climate change is predicted to affect the structure and function of freshwater ecosystems including species richness, biodiversity, and range as the chemical and physical systems change. This can trigger a cascading effect effecting food web and ecosystem productivity. There is a marked northward decrease in the diversity of algae and aquatic mosses and fish species; yet they remain an important resource. It is likely that many local Arctic species will disappear from certain locations when they are no longer able to adapt to the changing conditions. Although an Arctic wide extinction is not anticipated, some species are expected to diminish. Wetlands are the most abundant and productive aquatic ecosystems throughout the Arctic and in some cases, provide valuable carbon storage. They cover 11% of the Arctic land surface and have greater biodiversity than other Arctic freshwater ecosystems. Wetlands, along with the other aquatic ecosystems are home to hundreds of millions of migratory birds and are particularly sensitive to climate …show more content…
It is strongly absorbs solar radiation, is refractory and insoluble in water. During combustion, graphite particles, tens of nanometers in size are formed but rapidly change after emission as they collapse into dense clusters, take up water and combine with other co-emitted aerosols and gases (P. K. Quinn et al., 2008). Black carbon is naturally occurring but a large portion of atmospheric BC is the anthropogenic and transported to Alert by circulation systems which bring BC along with other aerosols from many other locations. Alert is primarily influenced by BC emissions from Siberia/ Europe during late winter and spring and regional sources in the summer (Sharma, Andrews, Barrie, Ogren, & Lavoué, 2006). These circulation patterns are created as wind vectors travel along mostly persistent pressure centres. The Arctic as a whole receives pollution through several of these circulation patterns. Alert, in particular, is mostly affected by the Siberian High, anti-cyclonic flow from Greenland, and winds from the polar vortex which transports pollutants from the central Arctic. The majority of Arctic BC is due to distant sources originating from agricultural burning, wildfires, residential burning, off-road diesel, and industrial combustion (“Arctic Report Card - Black Carbon in the Arctic - Sharma, et al.,
The Arctic is often defined using political, climatic, biological zoning and varies greatly amongst Arctic nations. Using geophysical definition as the land and sea, north of the Arctic Circle and which experiences polar day from April to September, and polar night from October to February. Overall, Arctic climate varies greatly by location with annual mean surface temperatures of 4C in Reykjavic Iceland, to -28 C at the crest of the Greenland Ice Sheet. Even within Canada there is much variation and the vastness of the Arctic make it difficult to generalize about its climate but some trends are observable. Overall, the three coldest months are January to March and are often considered …show more content…
Large rivers connecting the interior to the Arctic Ocean and smaller tundra streams transport heat, water, nutrients, contaminants, sediment, and biota and greatly affect the regional environments. There are permanent standing waters of various sizes that include small, shallow tundra ponds, and larger, deeper water bodies. Climate change is predicted to affect the structure and function of freshwater ecosystems including species richness, biodiversity, and range as the chemical and physical systems change. This can trigger a cascading effect effecting food web and ecosystem productivity. There is a marked northward decrease in the diversity of algae and aquatic mosses and fish species; yet they remain an important resource. It is likely that many local Arctic species will disappear from certain locations when they are no longer able to adapt to the changing conditions. Although an Arctic wide extinction is not anticipated, some species are expected to diminish. Wetlands are the most abundant and productive aquatic ecosystems throughout the Arctic and in some cases, provide valuable carbon storage. They cover 11% of the Arctic land surface and have greater biodiversity than other Arctic freshwater ecosystems. Wetlands, along with the other aquatic ecosystems are home to hundreds of millions of migratory birds and are particularly sensitive to climate …show more content…
It is strongly absorbs solar radiation, is refractory and insoluble in water. During combustion, graphite particles, tens of nanometers in size are formed but rapidly change after emission as they collapse into dense clusters, take up water and combine with other co-emitted aerosols and gases (P. K. Quinn et al., 2008). Black carbon is naturally occurring but a large portion of atmospheric BC is the anthropogenic and transported to Alert by circulation systems which bring BC along with other aerosols from many other locations. Alert is primarily influenced by BC emissions from Siberia/ Europe during late winter and spring and regional sources in the summer (Sharma, Andrews, Barrie, Ogren, & Lavoué, 2006). These circulation patterns are created as wind vectors travel along mostly persistent pressure centres. The Arctic as a whole receives pollution through several of these circulation patterns. Alert, in particular, is mostly affected by the Siberian High, anti-cyclonic flow from Greenland, and winds from the polar vortex which transports pollutants from the central Arctic. The majority of Arctic BC is due to distant sources originating from agricultural burning, wildfires, residential burning, off-road diesel, and industrial combustion (“Arctic Report Card - Black Carbon in the Arctic - Sharma, et al.,