The document describes Earthster Core Ontology (ECO), a domain ontology for Life Cycle Assessment (LCA). ECO aims to provide a vocabulary for core LCA concepts to publish LCA data on the web in a semantically interoperable way. It defines concepts like Process, Quantified Effect, and Elementary Flow. ECO is still under development with feedback from the LCA community. Its goals are to extend existing LCA data structures, link data sources, and allow for flexible extension over time as the field evolves.

1. Earthster Core OntologyA core domain ontology for Life Cycle Assessment

2. IntroductionsEarthster is a project, led by Greg Norris, to provide free open source solutions supporting Life Cycle Analysis – that is evaluating the environmental and social impacts of products. Brian McBride is a consultant, ontologist, developer and general dogsbody who has worked on semantic web technologies since 2000. He was co-chair of the RDFCore WG in W3C and the initiating developer of the Jena Java library.Epimorphics is a Semantic Web startup based in the UK specialising in Linked Open Data. http://www.earthster.org/http://www.epimorphics.com/

3. MenuA little bit about LCAWhy semantic web?A fragment of ECOA sense of the restThe ECO-systemA little bit on methodERF – an applicationWrapupSeason to taste with questions and discussion anytime

4. Life Cycle AssessmentWhat is a product’s impact on the environment and society?In production aka cradle to gate?In use – total lifecyle?

5. Life Cycle AssessmentImpact assessment is currently a complex, artful process – this description is considerably simplified

6. Define the goals of the assessment

7. Analyse your supply chain

8. Create an inventory of emissions and aggregated along the supply chain

9. Assess the impact of those effects on issues of interest e.g. global warming, human health, ...

10. There are impact assessment methods that define weighted contributions and give a score e.g. Emissions of CO2equivalent for GHG or DALYs for human health.Earthster Aim:Publish LCA Data on the WebTo inform folks about the sustainability implications of the decisions we makeAt all points in the supply chain:Simple measures for the consumer Decision support for the industrial buyerDetailed information for the product/process designerEnable consumer pressure to flow back down the supply chain to improve the sustainability characteristics of products

11. Why Semantic Web?EffectsPublish the data on the web makes it most freely available – and that is what the semantic web is forLinking to other data sources – that is what Linked Open Data is forFind an alternative pesticide that targets the same class of organismLink to Good Relations dataOperationsInteroperabilityHarmonize competing systems by defining a common conceptual modelHarmonize competing vocabularies by defining common reference dataLCA research is ongoing – the data required is changing over timeFinding the best available data

12. ECO: A Core Domain OntologyAim is to offer a vocabulary for core concepts in LCANot lists of instancesInstances are present if they are a logical necessity of the conceptCore ontology changes when core concepts change not when a new instance is inventedTrying to express the consensus conceptual model for the field Reverse engineering existing file formats and database schemas

13. A Fragment of ECO - 1ProcessModelModels Distinguish between statements about a process and a model of the process

14. Allows multiple inconsistent descriptions of the process with a contradiction

15. Gives us somewhere to hang model metadata without named graphs or reificationA Fragment of ECO – 2ProcessModelQuantified EffecthasQuantifedEffectModelsQuantityEffect Effect is a new abstraction not found in current LCA data structures

16. Key feature is that it is aggregatable

17. Abstraction of product flow, waste flow, elementary flow, land use, wages paid, ...

18. Don’t yet know if it will stick with the LCA community A Fragment of ECO - 3ProcessModelQuantified EffecthasQuantifedEffectModels Follows the SUMO upper ontology model for quantities and units

19. Adds the notion of an uncertainty distribution – not part of SUMO

20. There is a separate ontology of uncertainty distributions – they are not a logical necessity of the concept of an uncertainty distribution

21. What about the Zero uncertainty distribution – that is a logical necessityQuantityEffectmagnitudeunitsUncertainty distribution

22. A Fragment of ECO - 4LakeWaterSO2Quantified EffectQuantityElementary FlowCurrent LCA data structures have a fixed set of possible elementary flows, or at best a fixed set of properties of elementary flowsmagnitudeunitsUncertainty distribution

23. A Fragment of ECO - 5LakeWaterSO2Quantified EffectQuantityElementary FlowECO allows for more flexibility than that e.g. Could specify the size of the lake into which they emissions occur or provide some information about the kind of fish that live in it

24. Should we have allowed that extension:

25. giving in to the temptation to ‘improve’ the current shared conceptual model

26. done in a way that extends the legacy and does not contradict it