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[en] The Canadian government's overall approach to resolving the environmental problems due to global warming is discussed, with reference to how this approach is related to actions taken by other countries. Canada's environmental strategy is based the need to correct the failure to take into account the environmental consequences of daily actions. One element seen necessary for such correction, better environmental decisionmaking, is underlain by such key factors as the need to provide a strong scientific base on which to make decisions, resolving uncertainties regarding the greenhouse effect, and an environmentally educated population. Direct governmental measures can be taken to factor environmental considerations into decisions, such as regulatory instruments regarding the environment and economic incentives to encourage taking the environment into account. With respect to global warming, Canada has signed the Hague Declaration on international cooperation to reduce greenhouse gas emissions. About half the annual world emissions of greenhouse gases come from fossil fuel combustion. Canada is the fourth largest producer per capita of the single most important greenhouse gas, carbon dioxide. The transport and industrial sectors each account for ca 25% of Canada's CO2 emissions, and energy conservation is seen as a first step in reducing these emissions. The greatest scope for reducing greenhouse gas emissions in the transport sector appears to lie in the development of convenient and economic alternate fuels
[en] Pavements comprise an essential and vast infrastructure system supporting our transportation network, yet their impact on the environment is largely unquantified. Previous life-cycle assessments have only included a limited number of the applicable life-cycle components in their analysis. This research expands the current view to include eight different components: materials extraction and production, transportation, onsite equipment, traffic delay, carbonation, lighting, albedo, and rolling resistance. Using global warming potential as the environmental indicator, ranges of potential impact for each component are calculated and compared based on the information uncovered in the existing research. The relative impacts between components are found to be orders of magnitude different in some cases. Context-related factors, such as traffic level and location, are also important elements affecting the impacts of a given component. A strategic method for lowering the global warming potential of a pavement is developed based on the concept that environmental performance is improved most effectively by focusing on components with high impact potentials. This system takes advantage of the fact that small changes in high-impact components will have more effect than large changes in low-impact components.