• Journal of Korean Society of Environmental Engineers
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• v.29 no.6
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• pp.722-727
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• 2007

Life Cycle Assessment(LCA) is a tool that quantifies the inputs and outputs, md evaluates the potential environmental impacts during the entire life cycle of a product, material and/or service. Inputs and outputs encompass the consumption of natural resources and emission of pollutants to the environment. One of the deficiencies of the conventional LCA methodology is that it does not consider time explicitly. In addition, there are problems associated with the temporal boundary in the normalization step of LCA. The objective of this study is to propose a new life cycle assessment method that considers time in LCA as called 'Time Load LCA'. Basically Time Load LCA is a method that divides environmental load in each life cycle stage by time duration in each life cycle stage. Time consideration in the proposed method indicated that the new LCA method not only renders new perspective on the environmental impacts of a product system but also rectifies inconsistency in temporal dimension of the normalization step. Basic premise of the time load LCA method is that same amount of load over a shorter time period would affect more seriously on the environment than over a longer time period. therefore, load per time is necessary for the assessment of an impact of the inventory parameters on the environment.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.4
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• pp.358-383
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• 2015

The concept of 'carbon footprint' has been developed as a means of quantifying the specific emissions of the greenhouse gases (GHGs) that cause global warming. Although there are still neither clear definitions of the term nor rules for units or the scope of its estimation, it is broadly accepted that the carbon footprint is the total amount of GHGs, expressed as $CO_2$ equivalents, emitted into the atmosphere directly or indirectly at all processes of the production by an individual or organization. According to the ISO/TS 14067, the carbon footprint of a product is calculated by multiplying the units of activity of processes that emit GHGs by emission factor of the processes, and by summing them up. Based on this, 'carbon labelling' system has been implemented in various ways over the world to provide consumers the opportunities of comparison and choice, and to encourage voluntary activities of producers to reduce GHG emissions. In the agricultural sector, as a judgment basis to help purchaser with ethical consumption, 'low-carbon agricultural and livestock products certification' system is expected to have more utilization value. In this process, the 'cradle to gate' approach (which excludes stages for usage and disposal) is mainly used to set the boundaries of the life cycle assessment for agricultural products. The estimation of carbon footprint for the entire agricultural and forestry sector should take both removals and emissions into account in the "National Greenhouse Gas Inventory Report". The carbon accumulation in the biomass of perennial trees in cropland should be considered also to reduce the total GHG emissions. In order to accomplish this, tower-based flux measurements can be used, which provide a direct quantification of $CO_2$ exchange during the entire life cycle. Carbon footprint information can be combined with other indicators to develop more holistic assessment indicators for sustainable agricultural and forestry ecosystems.