Impacts of boreal forest fires on the environment in a changing climate

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Impacts of Boreal Forest Fires on the Environment in a Changing Climate     Climate change is expected to cause warmer temperatures through much of northern Canada.  This will likely increase forest fire and release more carbon and other greenhouse gases to the atmosphere from combustion, increasing the global warming effect.  The occurrence of fire also determines the vegetation of the boreal forest and dictates the amount of carbon that the forest will sequester.  Fire changes the surface characteristics of the forest, because new regenerating vegetation reflects more solar energy and alters the energy partitioning of heat and evapotranspiration.  This alteration of surface energy dissipation affects local, regional and global climate.  The research program will integrate the impact of fire on the carbon and energy balances to establish the net effect of boreal forest fire on the Earth's climate.  The research will estimate the magnitude of future combustion emissions of greenhouse gases and pollutants using global climate model projections of weather impacts on the area burned and the fire severity.  The post-fire effects on the carbon balance from recent flux studies will be integrated with the combustion losses to provide a total estimate of the greenhouse gas implications.  Analyses of the surface energy balance changes following fire will employ data from direct measurements at forested sites and from remote sensing.  The carbon and energy effects will be combined to provide a common net forcing function for fires, which will be projected over the next 100 years.  The research will evaluate the contrasting concepts that more fire causes a positive climate-warming feedback by increasing greenhouse gas emissions but causes cooling by increasing the Earth's reflectivity to solar radiation.  A centre for training students in the fields of fire, micrometeorology, carbon dynamics and climate change will be established.  This fire ecosystem approach will provide the first net estimate of the fire effect on climate, affecting policy decisions on the way that fire is considered in coping with global climate change.