METHODOLOGY

IMPACT World+ Framework

WorldImpactDetailedFramework

Additional informations on IMPACT World+

Most of the regional impact categories have been spatially resolved and all the long-term impact categories have been subdivided between shorter-term damages (over the 100 years after the emission) and long-term damages. IMPACT World+ provides consistent characterization factors for all regionalized impacts at four complementary resolutions: global default, continental default, country default, and native (i.e. original and non-aggregated) resolutions.

IMPACT World+ enables the practitioner to parsimoniously account for spatial variability and to identify the elementary flows to be regionalized in priority to increase the discriminating power of LCA.

 

This method, named IMPACT World+, is the update of the IMPACT 2002+, LUCAS, and EDIP methods. The IMPACT World+ method integrates developments in the following categories, all structured according to fate (or competition/scarcity), exposure, exposure response, and severity:

  1. Complementary to the global warming potential (GWP100), the IPCC Global Temperature Potentials (GTP100) are used as a proxy for climate change long-term impacts at midpoint. At damage level, shorter-term damages (over the first 100 years after emission) are also differentiated from long-term damages.
  2. Marine acidification impact is based on the same fate model as climate change, combined with the H+ concentration affecting 50% of the exposed species.
  3. For mineral resources depletion impact, the material competition scarcity index is applied as a midpoint indicator.
  4. Terrestrial and freshwater acidification impact assessment combines, at a resolution of 2°x 2.5° (latitude x longitude), global atmospheric source-deposition relationships with soil and water ecosystems sensitivity.
  5. Freshwater eutrophication impact is spatially assessed at a resolution grid of 0.5°x0.5°, based on a global hydrological dataset.
  6. Ecotoxicity and human toxicity impact is based on the parameterized version of USEtox for continents. We consider indoor emissions and differentiate the impacts of metals and persistent organic pollutants for the first 100 years from longer-term impacts.
  7. Impacts on human health related to particulate matter formation are modeled using the USEtox regional archetypes to calculate intake fractions and epidemiologically derived exposure response factors.
  8. Water consumption impacts are modeled using the consensus-based scarcity indicator AWARE as a proxy midpoint, whereas damages account for competition and adaptation capacity.
  9. Impacts on ecosystem quality from land transformation and occupation are empirically characterized at the biome level.

For more details on IMPACT World+, the scientific article in open access is available here.