Warming will result in: surface temp increase of 4 - 10 deg for northern canada, with the greatest increases occuring near the sea due to changing sea ice patterns.
These changes will affect the soil
Higher Autumn precipitation can be expected leading to more snow cover and insulation for the permafrost, hindering the cooling of it.
An increase in the speed of the spring warmth will cause snow melt, however as the ground is still frozen this could cause flooding as all the snow becomes run off.
Higher summer air temp and increased evaporation will result in greater wildfire frequency removing the organic later insulating the ground.
This will cause the active layer to deep/thicken => melting permafrost. In discontinuous permafrost it could disappear completely.
Smith 1988 stated a critical temperature of -3 for permafrost in order to halt/reverse melting.
If permafrost melts yet still exists discontinuously, then the area of cryosols(permafrost no more that 2 meters beneath the surface) is drastically reduced.
Degradation of cryosols leads to the formation of brunisols/gleysols. Their respective carbon balances are very different to cryosols as they store carbon for a much shorter time, so wildfires would reduce more carbon into the atmosphere that if it were cryosol.
Increased wildfire extent and frequency also leads to the removal of organic soils and trees, and can cause deep carbon to be exposed initiating decomposition.
48% of carbon stored in cryosol stated as severe or very severe risk and it is likely that substantial amounts of carbon will be released.
To summarise a lot of deep stored carbon would not be released if permafrost did not melt so much.

	Criado por samflint93 mais de 12 anos atrás

University finals GEOG3004 (2 Drivers & Contrasts) Notas sobre Supplementary reading L2, criado por samflint93 em 07-10-2013.

Supplementary reading L2