Using a Simple Knowledge Organization System to facilitate Catalogue and Search for - PowerPoint Presentation

Slide1

Using a Simple Knowledge Organization System to facilitate Catalogue and Search for theESA CCI Open Data Portal

EGU

, 21 April 2016

Antony Wilson

, Victoria Bennett, Steve

Donegan

, Martin

Juckes

,

Philip Kershaw

, Ruth Petrie, Ag Stephens, and

Alison

Waterfall

OverviewESA CCI and the open data portalChallengedifferent data sources

provide a range of search and data services

Solution

Use of linked data and SKOS

ESAClimate Change InitiativeEarth observation data

13

essential climate variables (

ECVs

)

Multiple sourcesDifferent scientific communitiesHeterogeneous data

The ChallengeProduce an Open Data Portal

Establish

a central repository to bring together the data from

multiple

sources and make

them available in a consistent way, in order to maximize their dissemination amongst the international user community

Data Reference SyntaxA data reference syntax (DRS) was developed by the Earth System Grid Federation (

ESGF

) to support CMIP5

Storage and discovery of

model

dataConcept of DRS reused for CCI, but focussing on observation

dataDefines a number of grouping /

facets common to all observationsThe CCI DRS was

agreed and published in a standards documenthttp://cci.esa.int/sites/default/files/CCI_Data_Requirements_Iss1.2_Mar2015.pdf

data type

institute

platform

sensor

essential climate variable (

ecv

)

product

processing level

time frequency

data scientist adds metadata

cataloguing

searching

standards document

output data

CataloguingData are archived at the Centre for Environmental Data Analysis (CEDA)

CEDA

are responsible for the

cataloguing of the data

Data from

13 different providersMetadata encoded in:

The file name2 different formats

Attributes of NetCDF files

data scientist adds metadata

validation

cataloguing

searching

vocabulary server

machine interface

machine interface

machine interface

human interface

output data

standards document

Vocabulary Server

Vocabulary ServerSingle point of authority of the DRSThe use of SKOS to

represent the

DRS

is well suited to deal with

its complexity

and varietySKOS provides:a means to represent controlled vocabularies a way to represent relationships between similar terms used in different

ECVsa way to easily represent hierarchies and navigation up and down hierarchies of

termsData is stored in a triple store with a SPARQL endpoint

http://

vocab-test.ceda.ac.uk/collection/cci/sensor

a

skos:Collection

;

skos:

prefLabel

"Sensor"@

en

;

dc:title "Sensor"

;

dc:

description

"The sensors that have been used in the collection of the data for the ESA Climate Change Initiative (CCI)." ;

dc:creator "Science and Technology Facilities Council" ; dc:date

"2016-03-22" ; dc:publisher "STFC"@en

; rdfs:comment "This collection represents the sensors used by the CCI project" ;skos:member

<http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_aatsr>, <http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_ace>, <http://vocab--test.ceda.ac.uk/collection/cci/sensor/sens_meris>

<http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_meris> a skos:Concept ;

skos:

prefLabel

"

MERIS

"@

en

;

skos:

definition

"Medium-Spectral Resolution, Imaging Spectrometer"@

en

;

cci:hasPlatform <http://vocab-test.ceda.ac.uk/collection/cci/platform/plat_envisat>

.

SKOS

searching

machine interface

cataloguing

data scientist adds metadata

human interface

output data

validation

MOLES (ISO19156)

vocabulary server

machine interface

machine interface

ESGF

Publisher

OGC

CSW

ISO19115

records

machine interface

search data files

CCI Open

Data Portal

search datasets

u

nder development

http://

vocab-test.ceda.ac.uk/collection/cci/sensor

a

skos:Collection

;

skos:

member

<http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_aatsr>,

<http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_ace>, <http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_aceFts>, <http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_airs>,

<http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_amiWs>,

<http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_amsr2>,

<http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_amsre>,

<http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_amsu>,

<http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_asar>,

<http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_ascat>,

<http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_aster>, <http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_atsr>, <http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_avhrr>, <http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_avhrrGac>,

<http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_avhrrHrpt

>,

<http://vocab-test.ceda.ac.uk/collection/cci/sensor/sens_meris> a

skos:Concept

;

skos:

prefLabel

"

MERIS

"@en

;

skos:

definition

"Medium-Spectral Resolution, Imaging Spectrometer"@

en ;

cci:hasPlatform <http://vocab-test.ceda.ac.uk/collection/cci/platform/plat_envisat> .

<

csw:GetRecords

xmlns:csw

="http://www.opengis.net/cat/csw/2.0.2" service="

CSW

" version="2.0.2"

resultType="results" outputSchema="http://www.isotc211.org/2005/gmd">

<csw:Query typeNames="csw:Record"><csw:ElementName>/gmd:MD_Metadata

</

csw:ElementName

>

<

csw:Constraint

version="1.1.0"> <Filter xmlns="http://www.opengis.net/ogc" xmlns:gml="http://www.opengis.net/gml">

<And> <PropertyIsEqualTo> <PropertyName>

keywordUri

</

PropertyName

>

<Literal>

http://

vocab-test.ceda.ac.uk/collection/cci/sensor/sens_meris</Literal> </

PropertyIsEqualTo> </And> </Filter> </csw:Constraint> </csw:Query

></csw:GetRecords>' http://csw1.cems.rl.ac.uk/geonetwork-CEDA/srv/eng/csw-CEDA-CCI

ConclusionsVocabulary server enables central management ofControlled vocabularies

Definitions of terms

Relationships between term, internally and externally

Assists in integrating multiple services, providing richer content

Reuse by

CLIPC projectMake use of NERC vocabulary server

AcknowledgementsTelespazio VEGA UKUniversity of ReadingCGI

Centre for Environmental Data Analysis

Scientific Computing, RAL

This

project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no

607418