GI standards and the WIS - Clemens Portele Report on using Geographic Information standards (ISO 19100, OGC) in the planning of the WIS with a focus on metadata Clemens Portele – interactive instruments GmbH

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Overview This presentation addresses four topics: Topic A: Assessment of the ISO series and OGC specifications; identification of standards that have the highest priority in order to deliver a workable metadata system in the WIS plus such that are relevant for supporting the work of the data provision centres Topic B: WMO Core Profile of the ISO metadata standard; identification of issues and recommendations; coverages vs features Topic C: Metadata tools Topic D: High level road map

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele WMO Information System (WIS) In 2003 WMO approved the concept of a WIS. The WIS will provide a single coordinated global infrastructure for the collection and sharing of information in support of all WMO and related international programmes.

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic A: Assessment of ISO series plus OGC specifications Identify a subset of the standards that have the highest priority in order to deliver a workable metadata system in the WIS Identify a further subset of standards that is required to support the work of the data provision centres being designed by the WIS team Note: The following assessment was done after a brief analysis and discussion of the WIS (metadata) requirements with WMO experts and is intended as a starting point for the future work within WMO

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele WIS tasks (simplified) Node Consumer (Client) Retrieve data Subscribe to data Discover data (retrieve metadata) Abstracted from the requirements, scenarios, use cases as described in [SIMDAT] Node = GISC, NC, DCPC

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele WIS tasks (simplified) Node Provider (Client) Send data Send metadata Abstracted from the requirements, scenarios, use cases as described in [SIMDAT] Node = GISC, NC, DCPC

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele WIS tasks (simplified) Node Admin (Client) Manage node Monitor and control node Manage users, data policy and billing Abstracted from the requirements, scenarios, use cases as described in [SIMDAT] Node = GISC, NC, DCPC

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele WIS tasks (simplified) Node Send data Send metadata Request data (returns data) Request data (returns reference + maybe credentials) Node Abstracted from the requirements, scenarios, use cases as described in [SIMDAT] Node = GISC, NC, DCPC

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele WIS tasks (simplified) Authenticate user Authorize user Log actions Manage real-time data Node Watch subscriptons Abstracted from the requirements, scenarios, use cases as described in [SIMDAT] Node = GISC, NC, DCPC

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Relevant standards for WMO (WIS, metadata) Metadata standards (including drafts): ISO/TC 211 ISO Metadata ISO Metadata extension for imagery and gridded data ISO Services ISO/TS – XML Schema implementation of ISO OGC OGC Catalog Service ebRIM Application Profile of the OGC Catalog Service (Web Registry Service) ISO 19115/19119 Application Profile of the OGC Catalog Service See Topic B for details Adopted/Published document Draft document documents with high relevance (underlined)

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Relevant standards for WMO (WIS, metadata) Data quality standards ISO Quality principles ISO Quality evaluation procedures ISO – Data quality measures Reference Model ISO – Reference model ISO – Reference model (Imagery)

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Relevant standards for WMO (WIS, metadata) Application schemas, feature catalogues, data product specifications ISO Rules for application schema ISO Feature cataloguing methodology ISO Data product specification Coverages / Imagery and gridded data ISO Schema for coverage geometry and functions ISO Imagery, gridded and coverage data framework ISO Sensor and data model for imagery and gridded data

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Relevant standards for WMO (WIS, metadata) Spatial information ISO Spatial schema ISO Spatial referencing by coordinates ISO Spatial referencing by geographic identifiers Temporal information ISO Temporal schema ISO – Schema for moving features

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Relevant standards for WMO (WIS, metadata) Registers and registries ISO – Procedures for registration of geographic information items OGC Catalog Service ebRIM Application Profile of the OGC Catalog Service (Web Registry Service) Encoding OGC Geography Markup Language (GML) / ISO ISO/TS – XML Schema implementation of ISO OGC GML in JPEG 2000 for Geographic Imagery (GMLJP2)

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Relevant standards for WMO (WIS, metadata) Data Access Web Services OGC Web Map Server Interface (WMS) / ISO OGC Web Feature Service (WFS) / ISO OGC Filter Encoding / ISO OGC Web Coverage Service (WCS) Portrayal ISO – Portrayal OGC Styled-Layer Descriptor

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Relevant standards for WMO (WIS, metadata) Sensors and Sensor Web Enablement OGC Sensor Observation Service OGC Sensor Planning Service OGC Sensor Alert Service ISO Sensor and data model for imagery and gridded data Geographic Digital Rights Management (GeoDRM) OGC GeoDRM Reference Model

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B: WMO Core Profile of the ISO metadata standard Consistency of the WMO Core Profile of the ISO metadata standard with future evolution of the ISO family of standards Key omissions that would prevent widespread uptake of data described using the WMO Core Profile among other communities Use of Coverages vs Features a combination of both to describe data of interest to WMO

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Metadata standards overview (including drafts) ISO Metadata ISO Metadata extension for imagery and gridded data ISO Services ISO/TS – XML Schema implementation of ISO OGC Catalog Service ebRIM Application Profile of the OGC Catalog Service (Web Registry Service) ISO 19115/19119 Application Profile of the OGC Catalog Service

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele ISO 19115: Metadata Identifies the metadata required to describe digital geographic data. Metadata is applicable to independent datasets, aggregations of datasets, individual geographic features, and the various classes of objects that compose a feature. Metadata shall be provided for geographic datasets and may, optionally, be provided for aggregations of datasets, features, and attributes of features. International Standard Used as basis for WMO Core Metadata Profile

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele ISO 19115:2003 Packages

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele ISO Part 2: Extensions for imagery and gridded data Extends ISO 19115:2003 Geographic Information – Metadata by defining the schema and additional metadata required for imagery and gridded data Still a Working Draft ! Not stable Recommendation: Monitor development Evaluate drafts Provide comments

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele ISO WD Part 2 Packages

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele ISO/DTS – XML Schema implementation Given the abstract nature of the ISO specification, the actual execution of geographic information metadata could vary based on the interpretation of the metadata producers *). In an attempt to facilitate the standardization of implementations, this comprehensive dataset metadata implementation specification provides single UML interpretation and XML schema for carrying out the ISO metadata standard. This specification is meant to enhance interoperability by providing a common specification for describing, validating and exchanging metadata about geographic datasets, dataset series, individual geographic features, feature attributes, feature types, feature properties, etc. *) and it does, see WMO Core Metadata Profile XML vs other XML encodings of ISO 19115

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Approach of ISO/DTS Composed of three essential parts in the Requirements Clause: ISO expands Annex E of ISO to show all the metadata elements (Not XML Specific) ISO also defines new constraint types to further refine the metadata elements for implementation (Not XML Specific) ISO defines XML Schema for geographic information dataset metadata (XML Specific) Community profiles may extend schema of ISO ISO Abstract Specification ISO Implementation Specification XML Schema Community Profile UML UML UML ext XML Schema ext. Adaptation scripts ISO Implementation Specification Status: Submitted to ISO as DTS (Draft Technical Specification), but not yet published expected to be stable, but changes may still occur

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele ISO 19119:2005 – Services Scope: Identifies and defines architecture patterns for service interfaces used for geographic information and definition of the relationships to the Open Systems Environment model Presents a geographic services taxonomy and a list of example geographic services placed in the services taxonomy Prescribes how to create a platform-neutral service specification, and how to derive platform-specific service specifications that are conformant with this Provides guidelines for the selection and specification of geographic services from both platform-neutral and platform-specific perspectives.

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele ISO 19119:2005 Packages Service Model > Service Metadata > Identification information > Records and Class Metadata > Data quality information >

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele ISO 19119: Geographic services taxonomy Geographic human interaction services Geographic model/information management services Geographic workflow/task management services Geographic processing services Geographic processing services – spatial Geographic processing services – thematic Geographic processing services – temporal Geographic processing services – metadata Geographic communication services

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Proposed amendment to ISO 19119:2005 An amendment to Service Metadata defined in ISO has been proposed based on implementation experience and has been accepted by ISO/TC 211 as a new work item Changes are proposed to the abstract schema, primarily concerning the relation between service metadata and dataset metadata. The extensions being proposed to ISO stem from requirements arising as a result of the practical experience being made with services in a Spatial Data Infrastructure in connection with and a nationwide catalogue service and the countries/states/regions bordering it. Hence the extensions are proposed from the background of usage within spatial data infrastructures, following the publish-find-bind principle.

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele OGC Web Services Typical pattern of usage Publish Find Bind Search Engine Information Resources Chain

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele OGC Catalog Service and Profiles The OGC Catalog Service provides the ability to search and retrieval of descriptive information (metadata) on an information resource (dataset, service, schema, etc.) using the same set of fields, the same operations and get similarly structured results from different servers The OGC Catalog Service itself provides an abstract catalog access model and supports any metadata model with abstract query points Requires core queryable and core returnable properties based on Dublin Core metadata elements Three protocol bindings: CORBA, Z39.50/ISO 23950, and HTTP Expects companion Application Profile document to complete implementation Two Application Profiles available (next slides), both are OGC Recommendation Papers (i.e., not yet adopted specifications) Adopted OGC Implementation Specification, scheduled to be submitted to ISO/TC 211 for standardization

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele OGC Catalog Service Core queryable properties Enable simple cross-profile discovery, must be supported by all application profiles Current list: Subject Title Abstract AnyText Format Identifier Modified Type Envelope (lat-lon bounding box) CRS (coordinate reference system) Association (source and target resource plus relation name)

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele OGC Catalog Service Core returnable properties Permit the minimal implementation of a catalogue service independent of a companion application profile use of metadata returned from different systems and protocol bindings Expressed using the nomenclature and syntax of Dublin Core Metadata, ISO Current list: dc:title dc:creator dc:subject dct:abstract dc:publisher dc:contributor dc:date dc:type dc:format dc:identifier dc:source dc:language dc:relation dct:spatial dc:rights

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele ISO 19115/19119 Application Profile of the OGC Catalogue Service Manages metadata resource types for data and service descriptions based on ISO and ISO (including the proposed amendment) All characteristic metadata are searchable Assertions can be traversed that effectively define data and service associations Originated in SDIs in Germany and is in deployment in various parts of Europe Uses ISO/PDTS for the XML encoding of ISO OGC Recommendation Specification, expected to become an adopted specifciation

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele ebRIM Application Profile of the OGC Catalogue Service ebRIM = ebXML Registry Information Model (developed by OASIS, ) offers a method for defining and managing interoperable registries and repositories. General purpose registry that can be applied to describe data, services, schemas, documents, dictionaries, symbol libraries, etc. Adopts ebXML RIM metadata model for query on small set of common properties Can be used to implement the ISO19115/19119 Application Profile OGC Recommendation Specification, expected to become an adopted specifciation

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.1: Consistency / potential issues of the WMO Core Profile The core metadata elements of ISO are included in the profile XML encoding: It is expected that ISO/TS will become the de-facto standard for XML encoding of ISO data Recommendations: Use ISO/TS (not a WMO specific encoding) at least we communicating with external systems If more economic, it may make sense to continue to use the current proprietary encoding internally in a system Create a two-way mapping using XSLT between the two encodings to verify that a lossless mapping is possible

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.1: Consistency / potential issues of the WMO Core Profile Catalog Service support: It is expected that Catalog Services will be a standard mechanism to access metadata Recommendation: Map WMO Core Profile information to the core properties of the Catalog Service Test use of the Catalog Service with WMO Core Profile Extensions to ISO do not follow the extension mechanism specified in ISO Recommendation: Revise the WMS Core Profile to use the extension mechanism of ISO (and ISO/TS for XML Schema); see in particular Annex C of ISO 19115

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.1: Consistency / potential issues of the WMO Core Profile (394) allows only a single date and not a period Recommendation: Delete or period (as the dateTypes all reference an instant) or use the metadata extension mechanism (143) must be a code list entry but the WMO description suggests that other data types may be used, too Recommendation: Restrict to the use of the code list or use the metadata extension mechanism (n) row in the ISO data dictionary

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.1: Consistency / potential issues of the WMO Core Profile (39) is mandatory in the ISO Core metadata, but it is optional in he WMO Core Profile Recommendation: Use a default value if data has no text in a language (new) irregularPointSet is the domain of a multi point coverage for WMO internal use. For external use, the mandatory bounding box is used (currently codes are used to encode the irregular point sets). Recommendation: Use the metadata extension mechanism

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.1: Consistency / potential issues of the WMO Core Profile (new) keywordReferenceSource is meant to extend the topic category enumeration which is too restricted to be useful for WMO; the element is intended to be a detailed reference to a hierarchical, multi-language dictionary Recommendation: Create, Publish and maintain the dictionary in a registry; XML encodings can be based on GML = ISO gml:Dictionary (can be used to define hierarchical dictionaries) or ISO CT_Catalogue (supports dictionaries with multi-lingual entries) Reference this dictionary through the thesaurusName citation

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.1: Consistency / potential issues of the WMO Core Profile (357) the axis orientation (signConvention) is part of the datum definition and not of the unit of measure information; however, this was considered important by WMO as it is a constant source of errors and ISO was considered insufficient Recommendation: If the information shall be represented seperately, then an additional element should be defined using the extension mechanism to redundantly express this information – instead of encoding this in the unit information

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.1: Consistency / potential issues of the WMO Core Profile (new) HorizontalCoordinateType is redundant as the coordinate reference system of a geometry object is always provided as part of it Recommendation: Delete this metadata element; if the intention is to provide information about the coordinate reference system of the data (rather than the extent information), then this should be provided via the referenceSystemInfo element (341, 342) The definition of polygon is not consistent with ISO (which is used by ISO 19115); also, a polygon may contain holes Recommendation: Reference the types specified in ISO Spatial Schema

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.1: Consistency / potential issues of the WMO Core Profile (351) If the temporal primitive is not used, this is not an instance of EX_TemporalExtent Recommendation: Use the metadata extension mechanism to specify an extension of EX_TemporalExtent where extent is a TM_Period (beginDateTime,endDateTime) and referenceDateTime is added as an additional element (new) CalendarType Recommendation: Verfify, if temporal reference systems as defined in ISO (and GML/ISO 19136) are insufficient for WMO; if yes, create a metadata extension according to the rules; if no, delete this element

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.1: Consistency / potential issues of the WMO Core Profile (68) The note regarding the useLimitiation text is unclear. The data type is a free text, it is unclear what ISO parameters are Recommendation: clarify (285) Multiple formats Recommendation: Encode as multiple MD_Format instances – not in a single name element

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.1: Consistency / potential issues of the WMO Core Profile (new) WMO_Source (WMO centre identifier, required because currently a private, non-TCP/IP network is used, a URL is not sufficient) Recommendation: Use the metadata extension mechanism to specify the additional element (232) See Topic B.3

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.1: Consistency / potential issues of the WMO Core Profile Other questions and recommendations: (4) What are standard character sets? (10,11) should be fixed for a particular version of the WMO Core Profile; example: WMO Core Profile, 0.2 (187, 206): Do additional rules for the use and naming of coordinate reference systems exist? (365): Do rules for unique identifiers exist? (348,349): Does a list of well known Gazetteers exist? Are these online-accessible?

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.2: key omissions preventing uptake of WMO data in other communities Limited experience is available about which factors are key metadata elements and best practices to stimulate uptake of previously unknown data sets Some recommendations: Try to identify the questions asked by the (potential) users of other communities when looking for data that could be provided by WMO and assess whether the WMO core metadata answers the questions Test the use of WMO core metadata using existing metadata tools, in particular how easy it is to execute the identified scenarios Support metadata for both the initial discovery and the evaluation phase of metadata searches Provide information in searchable registries, including codelists, thesauri, units of measurements, etc.

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.3: Feature types, features and coverages in WMO metadata Feature Types are defined on the schema level Real-world objects (features) are instantiated as data; coverages are features (from ISO 19109)

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.3: Feature types, features and coverages in WMO metadata Feature Catalogue and Coverage descriptions in 19115: MD_FeatureCatalogueDescription is used to describe catalogues of feature types (not catalogues of features!) MD_CoverageDescription and MD_ImageDescription are used to describe individual coverages / images Some examples of potential WIS feature catalogues seem to represent individual coverages; this is not the intention of a feature catalogue MD_CoverageDescription is not sufficient for the requirements of WMO and would need to be extended to address the requirements It should be checked in how far MI_CoverageDescription of ISO/WD addresses at least some of the issues Feature

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic B.3: Feature types, features and coverages in WMO metadata Coverages are Features. Coverage types are Feature types. Probably both descriptions (feature catalogue and coverage descriptions) are required in WIS: It makes sense to describe the types of features (including coverages) that are provided by the WIS, otherwise potential users will have difficulties discovering the data products offered through the WIS In addition, it may also make sense to include specific coverage descriptions in the metadata, if it is expected that users may search or look for specific characteristics of the individual coverages Feature

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic C: Metadata software tools (only ISO19115-based and/or Catalog Service products) Catalog Service products (server and/or client with support for ISO metadata) ArcIMS Metadata Server ( ESRI GIS Portal Tool Kit ( Indicio ( deegree Web Catalog Service ( FREE) sdi.suite terraCatalog ( Cubewerx WRS ( RedSpider Catalog ( These include implementations of both Application Profiles Dedicated metadata capture tools M3Cat ( ANZLIC Metadata Entry Tool (MET) ( FREE; not yet available)

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic D: Identify high level road map A high level road map for implementing a standards- based metadata system to achieve the goals of WIS depends on the time frame, available resources and other constraints and conditions In general, an iterative, spiral development approach with manageable steps, gradually increasing scope and prompt validation is highly recommended

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Topic D: Identify high level road map Possible steps (based on discussions that led to this report): Define scenarios and test cases for the metadata system Scenarios for (meteorology/climatology) experts Scenarios for other users with less know-how... Review and update WMO Core Profile Clarify conformance issues Identify issues in the standards that do not address the WMO metadata requirements and report them and/or define WMO specific extensions (including ISO 19111, ISO 19108, ISO 19123) Develop mapping to Set up Catalog Service serving the metadata Execute test cases Review results and update specifications / add additional or more detailed specifications

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele Contact Information Clemens Portele interactive instruments GmbH Trierer Straße Bonn Germany

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele References [SIMDAT]SIMDAT Project Deliverable D Consolidated Meteorology Requirements, Version 1.1, [WMOCore]WMO Core Metadata Profile of ISO 19115, Version 0.2, August 2004 [WMOCoreXML]WMO Core Metadata Profile of ISO 19115, Version 0.2, August 2004 [HMMG]ISO/TC 211 Harmonized Model ( [19101]ISO 19101:2002 ( [ ]ISO WD (ISO/TC211/N1737), [19108]ISO 19108:2002 ( [19109]ISO 19109:2005 ( [19110]ISO 19110:2005 ( [19111]ISO/DIS rev. (sent to ISO Central Secretariat)

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele References [19115]ISO 19115:2003 ( [ ]ISO WD (ISO/TC211/N1697), [19117]ISO 19117:2005 ( [19119]ISO 19119:2005 ( [19123]ISO 19123:2005 ( [19129]ISO WD (ISO/TC211/N1869), [19130]ISO CD (ISO/TC211/N1772), [19135]ISO (sent to ISO Central Secretariat) [19139]ISO/DTS (sent to ISO Central Secretariat) [CAT]OGC Catalogue Service, OGC r2 [WRS]ebRIM Application Profile of [CAT], OGC r1 [CATAP]ISO 19115/19119 Application Profile of [CAT], OGC r2 [GMLJP2]GML in JPEG 2000 for Geographic Imagery, OGC r2

© 2005 interactive instruments GmbH GI standards and the WIS - Clemens Portele References [WMS]Web Map Service 1.3, OGC [WFS]Web Feature Service 1.1, OGC [WCS]Web Coverage Service 1.0, OGC r6 [FES]Filter Encoding 1.1, OGC [GML]Geography Markup Language 3.1, OGC r1 [OWS3]OGC Web Services Phase 3 initiative ( [GALEON]OGC GALEON WCS Interoperability Experiment ( [SAS]OGC Sensor Alert Service Interoperability Experiment ( [SWE]Sensor Web Enablement White Paper ( n=2&format=pdf)