Researchers from the Centre for Northern Studies (CEN, Universite Laval, Quebec) have documented two manifestations of planetary warming in northern Quebec. The first affects the acceleration of melting permafrost in subarctic peatlands, and the second increase in the vertical growth rate of trees in the limit of the drills.
In a recent issue of Geophysical Research Letters, researchers are to benefit the accumulated data on a bog situated at the height of 56e parallel, east of Hudson Bay, to describe the evolution of the permafrost in this habitat.
The researchers used an aerial photo taken in 1957 and data harvested on the field during inspections carried out every ten years between 1973 and 2003. They discovered that the percentage of the area of the bog occupied by permafrost is going to 82 1957% in a 13% in 2003. His disappearance rate has doubled since 1993. According to researchers, the main cause of this acceleration is the increase in precipitation as snow; snow cover protecting the soil against the wave of frost and dabbing temperature differentials. The impact of the degradation of peat on the gas balance of greenhouse remains measured.
Moreover, models of planetary warming are predicting that the current northern limit of the drills will gradually repulsed north. In an article recently published in the Journal of Ecology, the researchers provide that the Nordic expansion of black spruce - a species with limited reproductive capabilities - should be preceded by a change in wearing these trees according to their analysis the rod main tree known vertical growth accelerated from
1970 years. If current conditions continue, the spruce will continue their vertical growth and produce more cones and seeds; This front promote Nordic expansion of the tree.
Sources: John Hamann - Throughout the events, 10 / 03 / 2005 - Universite Laval