Methods to assess global environmental impacts from Swedish consumption : Synthesis report of methods, studies performed and future development

• The output of the project is a synthesis of methods to assess environmental impacts in other countries caused by consumption in Sweden. Over the last couple of years a number of studies have been performed testing methods and refining data sets for these types of studies. The following six areas of assessment are taken into account in this study: greenhouse gas emissions, other emissions to air, chemicals, water use, land use and biodiversity. The report includes short introductions to methods used in the different impact areas, references to performed studies and recent research. The data availability and available time series are mentioned as well as the methods’ strengths and weaknesses. The work is performed by literature studies, references to scientific articles, working papers and ongoing projects in Sweden and internationally. Generally, when calculating environmental impacts caused by consumption in other countries one can either use a bottom-up method or a top down method. In the first case the impacts caused during the production processes for each product that is consumed are summed (LCA based methods). In the other case a consumption view is applied, i.e. data on consumption of a whole nation is combined with environmental data for each industry branch and product categories (input-output based methods). There are also several hybrid methods, for example LCA methods that use input-output based data to fill in data gaps. Some of the methods described in this report are more suitable than others to use in further analyses, for example in designing policies. These methods are the ones which links environmental impact to the total economy in a nation. To get a useful indicator on the environmental pressures linked to consumption we recommend choosing a method which can be used in further analyzing. An input-output based model makes it possible to study what implications changes in consumption, or changes in emission intensities, can have on environmental impacts. For two of the six assessment areas there exist mature methods to assess environmental impacts in other countries caused by consumption in Sweden, namely for greenhouse gas emissions and other emissions to air. The recommended methods to use for these areas are the environmentally extended input-output model. Data and time series are published by Statistics Sweden. Even though these methods are considered mature, they are still under development and enhancements can be foreseen in a near future. To go further with these analyses, one could start looking deeper into the factors that the consumption model can provide. That means comparing results by product groups and also to focus on the improvement of environmental data that are needed to calculate country intensities, i.e. for emissions caused in the countries where the production process takes place. For emissions of chemicals we are suggesting to apply an input-output based approach, which to our knowledge, still has not been tried out for Sweden. We suggest using the Pollutant Release and Transfer Register (PRTR) which contains data on 90 emissions on substances by industry in an environmentally extended input output analyses. For chemicals there is a possibility to weight the chemicals according to an existing method or to work with specific chemicals. When weighting the chemicals a ”toxic potential” is obtained, which sums up the loads from different substances emissions. Emission intensities for different trade partners must be developed to get good result on emission in other countries. On the input side, i.e. the use of chemicals, there are experiences to use input-output analyses. For the three remaining areas, land use, water use and biodiversity there are no straight forward and ready to use methods or data sets. Instead we suggest initiating studies within the areas and point out possible ways to go forward. The assessment of these areas probably requires the dimension of the state in the environment, as the linkage between environmental impact and pressure is not always obvious. Regarding land use one can add the land use and land cover statistics to the inputoutput model. A prerequisite is to divide these data on industry branches. This has not been performed to a full scale and need to be initiated. Probably some reference to the state in the environment needs to be done, by using for example the HANPP index (human appropriation of net primary production in earth’s terrestrial ecosystem), in order to get interpretable results. The HANPP index gives a measure on how much biocapacity that is removed from the available biocapacity and is based on forestry and agriculture statistics, and global data is available. To get relevant land use data in the countries where the products that we import are produced the availability on international data must first be mapped. This method has yet to be tested before we can say how the results can be interpreted. A product view can be pragmatic in this area as a starting point. Critical products could possibly be identified, products known to be linked to negative land use effects, if experts can set up relevant criteria. The Swedish trade with these products can be analyzed, pointing out how Swedish consumption contributes to changes in land use in different countries. A possible way forward would be to utilize land use data for some major categories such as agriculture or forestry in the countries from which Sweden imports goods and gradually develop a database with more environmentally relevant information on the type of land use. Regarding water use one can add water use statistics to the environmentally extended input-output model. The availability on international data must first be mapped in order get relevant water use data in the countries where the products that we import are produced. This could be combined with some kind of index which indicates the state in the environment to be useful, as in the case of land use. Such an index is for example the water scarcity index which shows the global status in water basins. One could also apply a product perspective. It is known that agricultural products are those most related to water problems globally. These products can be identified in the Swedish trade, data can be analyzed and this together with the scarcity index could say something about Swedish consumption’s contribution to water related problems. These suggested methods have yet to be tested before we can say how the results can be interpreted. Biodiversity is a complex area and is also connected to the other areas to a large extent. There is no biodiversity index ready to use and probably not foreseen in a near future. However, if the five areas above are added to an environmentally extended input-output model they probably together give a relatively good measure on biodiversity related pressures. As a starting point, however, a product view can be useful to apply. In this case critical products must be listed, if this can be done by experts, so that the study of the trade with these can be performed. The outtake of wood and fish should at least be included in such a study. As the six areas of assessment differ in method and data availability there are several options for the scope of further studies and research. Firstly one can make the most mature methods even better, to make more accurate calculations and hence focus on greenhouse gas emissions and other emissions to air. Secondly, one can initiate new studies to increase the number of extensions in the input-output based calculations. Emissions of chemicals, is an extension that seem to be possible to add to the environmentally extended input-output model under some limitations. One can also focus on those diverse areas where no exact methods are available and initiate studies or research so that these can be linked to consumption in Sweden in a near future. Land use and water use can probably also be added to the environmentally extended input-output model, whereas biodiversity seem to be more distant. 

Ämnesord

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Miljövetenskap (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Environmental Sciences (hsv//eng)

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