FAQ

This is a short list of our most frequently asked questions. If you have any other question about LC-IMPACT, please use our Contact form.

 

1. What is the spatial differentiation of the characterization factors in LC-IMPACT?

The spatial differentiation in LC-IMPACT depends on the impact pathway modelled. For impact categories where impacts take place at a global scale only (climate change, ozone depletion, ionizing radiation) the characterization factors are given on a global level only. For categories with a regionalized scope, such as water and land stress, spatially differentiated characterization factors are derived. The highest spatial resolution depends on the relevant scale of the impacts and the data availability. For currently available spatially-differentiated impact categories the following spatial detail is available:

  • Water stress (Human health): watershed level (>11’000 spatial units)

  • Freshwater eutrophication: 0.5 ° x 0.5°

  • Terrestrial acidification: 2.0° x 2.5

In addition, characterization factors are also reported on a country and global level to increase the flexibility of the application. Country and global characterisation factors were calculated as the average of grid-specific CFs weighted by the fraction of the population of the countryor global living on that grid or weighted by the amount of resource (e.g. water) used.

2. Is there a midpoint level in the LC-IMPACT methodology?

No, there are currently only characterization factors at endpoint level available. It is our aim to include consistent midpoint indicators in a future update.

3. How complete is the LC-IMPACT methodology? 

The LC-IMPACT methodology includes many new and improved developments in LCA research, such as impacts from water and land stress, marine eutrophication or new toxicity impacts. Other impact pathways are still missing, for example the impact of noise on humans and ecosystems.

4. How are uncertainties dealt with in LC-IMPACT?

Scientific evidence of impact pathways is divided into high level and low level of robustness. Characterisation factors are reported for high level of robustness only and for high + low level of robustness, respectively.

5. Which units does the LC-IMPACT methodology use?

For human health, the endpoint unit is DALY, i.e. disability adjusted life years, in the population exposed.

For ecosystem quality, the  endpoint unit is PDF, i.e. potentially disappeared fraction of species at the global scale . Global species loss is derived on the basis of spatially differentiated global maps of today’s present number of species in various taxonomic groups, including vascular plants, fish, birds, mammals, amphibians and reptiles.

For resource scarcity, the endpoint unit is kgore, i.e. kilogram of ore which represents the extra average amount of ore produced as a result of mineral resource extraction.

6. Are intermediate impacts leading to species richness decrease (e.g. oxygen depletion in the water, aluminum toxicity, increase in primary productivity) included in the impact pathway models?

No, Since many different impact pathways are possible, the effect models included in the derivation of the characterization factors relate the concentration of the pollutant with the species richness decrease directly.

7. In the case of freshwater eutrophication, why are there no characterization factors provided for the Saharan desert?

In the freshwater eutrophication model, grids in very arid areas have no water. Therefore, there can be no emission of P to water, transport to downstream grids, or effect to freshwater species.

8. Why are only mineral resources included in the Area of Protection "Resources"?

Though fossil resource extraction is often included in the Area of Protection "Resources", this is not included in the LC-IMPACT methodology. Fossil resource extraction is highly correlated with Climate change.