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Rationale. Interoperability between the Geosciences (Earth Sciences) info Community and the Geo-Information CommunityData model Harmonization issuesProtocols adaptation issuesNon-functional issuesQuality of Service (e.g. Real-time access)Fault tolerance for critical missionsData policy and vol
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1. INSPIRE Architecture:Interoperability with the Geosciences Information Community Stefano Nativi1 and Gil Ross2
Members of INSPIRE Metadata Drafting Team
1 Italian National Earth & Environment Research Community (INTERO)
2 MetOffice UK
2. Rationale Interoperability between the Geosciences (Earth Sciences) info Community and the Geo-Information Community
Data model Harmonization issues
Protocols adaptation issues
Non-functional issues
Quality of Service (e.g. Real-time access)
Fault tolerance for critical missions
Data policy and volume
Trustworthiness
….
3. Data Model HarmonizationIssues
4. Earth Science (Geosciences) Info Communities Disciplinary Communities
Geology
Oceanography, limnology, hydrology
Glaciology
Atmospheric Sciences
Meteorology, Climatology, Aeronomy, …
Interdisciplinary Communities
Atmospheric chemistry
Paleoceanography and Paleoclimatology
Biogeochemistry
Mineralogy
….
Basic Disciplines
physics, geography, mathematics, chemistry and biology
5. Earth Science (Geosciences) Info Communities Disciplinary and Interdisciplinary models
6. Geographic Information Realm Stack of model layers
A couple of general models (see ISO 19100)
Boundary model
Coverage model
7. ES and GI Info realms Historical and technological differences:
8. ES and GI Info realms Historical and technological differences:
9. WMO case Observation and Forecast domain
Real time data involve observations from surface stations, ships, buoys, upper air balloons and in-flight aviation transmissions. There are also remote soundings from surface sites, radar and satellite soundings which are much greater in volume.
The raw data from forecasts are “fields” of individual parameters from Numerical Weather Prediction models (NWP).
Each NWP model run has values on 4 D grids, which are usually projected and sliced onto horizontal grids for dissemination.
The forecast fields are used to create summary forecast products to aid decision making which are also disseminated on the GTS.
Both the observational data and the forecast fields normally require processing for human consumption.
10. WMO case Observation and Forecast domain
WMO data or NWP (Numerical Weather Prediction) models do not have the resolution of geographic data
The highest resolution of NWP models in operation is about 4km;
The global models use typically a 50km grid resolution.
The trend is to higher resolutions, with limitations.
Models in the 1 km range, for example may need to resolve individual cloud processes.
A large part of WMO exchanged data is in the form of real-time data
WMO data are (almost) all spatio-temporal, and while (almost) every dataset has a spatial extent, the data is organized instead by date and time.
Data all have a time-stamped identifier, while there is (almost) no spatial information in the identifier.
11. WMO case Boundary and coverage models
No well-developed features (boundary) and coverage models for weather data
Projects are developing such models
Parts of WMO’s Weather Information System (WIS) project – a portal-like system to replace the GTS – are working on such models for the specification of all WMO real-time and climate summary data.
OGC experts on observation and measurements are involved in these projects
12. WMO case Metadata model
In practical terms there are effectively no WMO discovery metadata holdings for a general user
Metadata for public discovery are not generally available, in ISO discovery or any similar form.
WMO services do not have service metadata in the intended form
13. Service-Oriented Architecture
14. Distributed Systems Vs Architectural Styles
15. SOA: Service Oriented Architecture Suitable for extensible and heterogeneous distributed systems
Interoperability is granted by declaring in a self-contained, self-explanatory and neutral way
Application Interfaces
Service specification (protocol based; e.g. WSDL)
Payload data models (data encoding)
Important part of the service description; semi-structured models (e.g. XML schema)
16. SOA: payload data models harmonization GI realm
OGC GML (Geography Markup Language)
Product related
Google KML (Keyhole Markup Language) -- GoogleEarth
ESRI ArcXml (Arc eXtensible Markup Language) -- ArcIMS
Earth Science info realm
Plethora of new MLs
Holistic approach (at different model levels)
ESML, ncML, HDF XML encoding, GeoSciML, SensorML, etc.
Reductionist approach
Structural Geology ML (SGeoML)
Exploration and Mining ML (XMML)
MarineXML
Hydrological XML Consortium (HydroXC)
Climate Data ML (CDML)
Climate Science Modelling Language (CSML)
Digital Weather ML (DWML)
….
Binary Data Encoding format
GRIB, NetCDF, HDF, BUFR, …
17. SOA: Interface protocols adapters GI realm
OWS (i.e. WMS, WFS, WCS, CS-W, WPS, ….)
Product related
Google Map and Google Earth service interfaces
ArcIMS service interfaces
Earth Science info realm
Holistic approach (at different levels)
OPeNDAP, THREDDS catalog service, …
Reductionist approach
CDI, EOLI, …
18. WMO case Distribution systems
More Push than Pull-based
Several service buses
Global Telecommunications System (GTS)
highly resilient – and therefore costly - worldwide distribution system
The Weather Information System (WIS) project is a portal like system to supplement then replace the GTS
GEONETCast: a global network of satellite dissemination systems (involving inter alia, NOAA, WMO and EUMETSAT)
TV and Radio.
Architectural Style
None of the existing WMO services operate through Web Services
For services with the volume required for WMO operational services or WMO archives, Internet is unlikely to bear the load (bandwidth costs and constraints)
19. WMO case Data encoding
None of the WMO codes (alphanumeric and table-driven) have yet been converted to an agreed XML form,
This process is under consideration by the World Weather Watch Programme expert teams.
Information on observing stations and sensors are not formatted in XML
Table driven code forms include BUFR and CREX , and GRIB data forms.
20. WMO case Registry and Catalog services
There are lots of catalogues, but not in the form of a registry service.
This is under development in the WIS project
Almost all WMO registers are on-line documents or searchable databases.
The WMO catalogue for GTS data is available as a searchable database, and as published documents for the catalogue of bulletins, transmission schedule and information for shipping.
The catalogue of bulletins does not list bulletins by time, but it does list the bulletin and the originator – the disseminating station in WMO terms.
21. WMO case Registry and Catalog services
WMO Public Weather Services are browser based on NMHS websites and not of a standard form.
WMO metadata is document based, for WMO users.
22. WMO case View Services
WMO members do not offer view services as defined by INSPIRE
WMO view services (Public Weather Services) are referenced through related links, through NMHSs web services and through WMO PWS weather forecast offices.
It is difficult to mix the map paradigm for INSPIRE (to pan, zoom, navigate etc.) with the natural meteorological paradigm of time sequence and animation.
While it is technically possible to mix horizontal panning with time sequencing, it would be difficult for anyone to understand such a display.
The view service with time sequencing is a service which is missing from the INPIRE Architecture Overview.
23. WMO case Gazetteers Services
There are gazetteers of WMO registered observing stations, radiosonde stations, synoptic and climatological networks, and lists of observing ships.
This is not a gazetteer service in OGC terms.
24. WMO case Download Services
Example of available delivery services by request over Internet
Web Werdis Web Weather Request and Distribution System of DWD Deutscher WetterDienst
DPDS Data Production and Delivery System of the UK Met Office
Météo France secure download service.
A download service is not the usual or preferred mechanism by which the NMHSs distribute their data.
NMHSs do not rely on users actively requesting data.
Nearly all the data services are delivered by a regular dissemination of data to registered users.
There are always time-critical requirements, particularly for safety of life.
For security, reliability and robustness, these are usually disseminated over fixed links or dial-up rather than by Internet.
25. WMO Case Clearinghouse services
WMO’s Weather Information System (WIS) project is a portal-like system to subsume the GTS
It is highly unlikely that any purely geographic portal would have or would want to have the capability to handle meteorological data in the way the manner being designed for WIS.
26. References G. Ross, “World Meteorological Organisation data and services relevant to the INSPIRE Architecture Overview”, version 0.8, 15 January 2007.
S. Nativi, “Interoperability between Earth Sciences and GIS models: an holistic approach”, seminar at NCAR and UCAR-UOP, Boulder (CO) USA, 27 July 2006. available at http://www.unidata.ucar.edu/Presentations/UPCsemseries/Presentation_Nativi_2.ppt
For more information:
nativi@imaa.cnr.it
gil.ross@metoffice.gov.uk