Expressing weather observations as linked data;

Transcription

1 Expressing weather observations as linked data; ISO geographic information meets semantic web head on Jeremy Tandy Smile for the camera (Earth Observation) / Linking Geospatial Data 5 March 2014 Crown copyright Met Office Open Government License v2

2 World Meteorological Organisation (WMO) WMO specialised agency of the United Nations since 1951 weather, water and climate facilitates free and unrestricted exchange of data and information [ ] Met Office is WMO Member on behalf of UK Crown copyright Met Office 2

3 Weather, water and climate in context WMO meteorological information Crown copyright Met Office 3

4 Weather, water and climate in context WMO meteorological information geographic information Crown copyright Met Office 4

5 Building on broader standards: memorandum of understanding «mou» «mou» WMO TC 211 meteorological information geographic information Crown copyright Met Office 5

6 Geographic information: abstract specifications TC 211 abstract specifications Crown copyright Met Office metadata features geometry time spatial referencing coverages observations and measurements etc. 6

7 Geographic information: domain or application specific data models Application Schema ******** **** ******* ********* ********* «imports» ******** ** ******* ********** ** Modele pour l'echange des informations sur le Temps, le Climat et l'eau (METCE) ICAO Meteorological Information Exchange Model (IWXXM) WaterML2 TC 211 abstract specifications Crown copyright Met Office 7

8 Application Schema = semantic model Application Schema ******** **** ******* ********* ********* «imports» ******** ** ******* ********** ** Modele pour l'echange des informations sur le Temps, le Climat et l'eau (METCE) ICAO Meteorological Information Exchange Model (IWXXM) WaterML2 TC 211 abstract specifications technology independent description of content and structure of information to be exchanged for a given application: semantic model (logical model) Crown copyright Met Office 8

9 ISO/DIS Geographic information Ontology Part 2: Rules for developing ontologies in the Web Ontology Language () Application Schema ******** **** ******* ********* ********* «imports» ******** ** ******* ********** ** ontology geometry metadata temporal lineage feature dataset ISO/DIS provides systematic rules for converting Abstract Specifications and conformant Application Schema into ontologies as a result, we can use the semantic model defined in the Application Schema when publishing linked data TC 211 abstract specifications (logical model) coverage observat n sampling (physical model) Crown copyright Met Office 9

10 Example: simple weather observation data from Met Office Weather Observation Website (WOW) Air temperature of 11.2 C measured at 09:00 13-Dec-2013 using a sensor hosted on a weather station deployed at Exeter Airport weather station location (site ) Crown copyright Met Office 10

11 Example: simple weather observation RDF encoding using draft ontologies from basic: gm: tm: om: sam: < gm:position gm:srs < gm:coordinates gm:position gm:point tm:instant tm:datetimeposition T09:00:00Z < rdfs:label Celsius basic:uom basic:measure basic:value 11.2 sam:shape < sam:samplingpoint rdfs:label Exeter Airport (site ) om:featureofinterest om:phenomenontime om:result <site/ /date-time/ t0900z> om:measurement om:observedproperty < rdfs:label Air temperature dct:description The temperature indicated by a thermometer exposed to the air in a place sheltered from direct solar radiation. sam:sampledfeature sam:hostedprocedure om:procedure < os-50kgaz:namedplace rdfs:label Exeter Airport < om:process dct:description Unknown sensor 700db520-[...] at site OL RE OF URI LD Crown copyright Met < 11

12 Existing open vocabularies not a green-field site Linked Open Vocabularies (LOV) LOV provides an entry point into the growing ecosystem of linked open vocabularies (RDFS or ontologies) used in the Linked Data Cloud 410 vocabulary spaces (as of March 2014) Crown copyright Met Office 12

13 Example: simple weather observation RDF encoding using draft ontologies from basic: gm: tm: om: sam: < gm:position gm:srs < gm:coordinates gm:position gm:point tm:instant tm:datetimeposition T09:00:00Z < rdfs:label Celsius basic:uom basic:measure basic:value 11.2 sam:shape < sam:samplingpoint rdfs:label Exeter Airport (site ) om:featureofinterest om:phenomenontime om:result <site/ /date-time/ t0900z> om:measurement om:observedproperty < rdfs:label Air temperature dct:description The temperature indicated by a thermometer exposed to the air in a place sheltered from direct solar radiation. sam:sampledfeature sam:hostedprocedure om:procedure < os-50kgaz:namedplace rdfs:label Exeter Airport < om:process dct:description Unknown sensor 700db520-[...] at site OL RE OF URI < Crown copyright Met Office 13

14 Example: simple weather observation RDF encoding using ontologies in common qudt: < # Quantities, units, sf: < # Simple time: < # ssn: < # Semantic Sensor sam: < sf:point geo:aswkt < Point( ) sam:shape < sam:samplingpoint rdfs:label Exeter Airport (site ) sam:sampledfeature time:instant time:inxsddatetime T09:00:00Z ssn:featureofinterest sam:hostedprocedure < rdfs:label qudt:unit Celsius ssn:observationsamplingtime <site/ /date-time/ t0900z> ssn:observation qudt:unit ssn:observationresult ssn:observedby qudt:quantityvalue qudt:numericvalue 11.2 ssn:hasoutput ssn:sensoroutput ssn:observedproperty ssn:observes qudt:valuequantity qudt:quantity qudt:quantitykind < ssn:property, qudt:quantitykind rdfs:label Air temperature dct:description The temperature indicated by a thermometer exposed to the air in a place sheltered from direct solar radiation. < os-50kgaz:namedplace rdfs:label Exeter Airport < ssn:sensingdevice dct:description Unknown sensor 700db520-[...] at site OL RE OF URI < Crown copyright Met Office 14

15 Ontology harmonisation activity? community effort to make the vocabulary space less confusing Application Schema TC 211 ******** **** ******* ********* ********* «imports» ******** ** ******* ********** ** abstract specifications ontology geometry temporal metadata lineage feature dataset coverageobservat n sampling To further align the geographic information and Linked Data communities it is important that vocabularies in common usage are recognised and mapped to the Abstract Specifications Crown copyright Met Office 15

16 Crown copyright Met Office Thank you.