Coverages and Earth Observation in Linked Data (CEO-LD)

A starry night sky with a prominent streak showing the movement of a satellite

The UK and China are both at the forefront of Remote Sensing and Earth Observation technologies, with extensive scientific and commercial programmes to maximise the use of the huge amounts of data being beamed down from space every day. Lead by CODATA, the CEO-LD project brings together stakeholders from both countries who will help to establish how that data is best shared and exploited on the Web. This will be achieved via contributions to the Spatial Data on the Web Working Group, a collaboration between W3C and the Open Geospatial Consortium (OGC), enabling rapid progress to be made with that group's Coverages in Linked Data standard.


Spatial data is integral to many human endeavours and there is clearly high value in making it easier to integrate that data into Web-based datasets and services. The desire to make better connections between geospatial information systems and the Web is what triggered the formation of the W3C/OGC collaboration. That group is chartered to produce a set of best practices for publishing and using spatial data on the Web, and to complete the standardisation of the OWL Time Ontology and Semantic Sensor Network Ontology.

The CEO-LD project will ensure that Earth Observation (EO) imagery is a prime target for the remaining deliverable: Coverages in Linked Data. That is, how to use Web technologies to encode and access information related to points on a grid laid out across time and space. Things like land use, crop types and yields, ecological damage, moisture and soil maps, aircraft and shipping tracks, oceanographic and climate data.

Relationship with the Working Group

The CEO-LD project is separate from the standard-setting Working Group, participation in which is subject to the two standards bodies' normal rules. However, several members of the CEO-LD project are members of the WG and it is through them and the OGC and W3C staff that direct links will be maintained1.


In summary, the work programme for the CEO-LD project is as follows:

September 2015 Kick Off Seminar
The stakeholders will meet in London on Tuesday 29th – Wednesday 30th September 2015. The seminar will review the use cases and requirements already developed by the WG and suggest additions to that document as necessary. This fits in well with the expected publication of the second iteration of that document during September or October.
September 2015 – June 2016 Drafting the Coverages in Linked Data standard
The project will offer direct editorial support to the working group (through individuals who are members of both) to draft the standard. Stakeholders will hold regular conference calls to facilitate this.
26 – 27 October 2015 TPAC
The Spatial Data on the Web Working Group is meeting at W3C's big annual meeting TPAC which this year is being held in Sapporo, Japan. Members of the CEO-LD project are encouraged to join that meeting.
Spring 2016 Beijing Seminar
The second & final face to face meeting of the project was held in Beijing on Sunday 28th February 2016, organised by CODATA China and Beihang University (W3C's host in China). See the report.

The aim is to help the Working Group advance the Coverages in Linked Data as far as possible before calling for implementations. In W3C terms this means developing the standard to 'Candidate Recommendation.'


Crucial to success and to the growth of a large market will be international take-up of the resulting standard. To this end, the UK and Chinese National Committees of CODATA will report to its parent body, ICSU, and through that to other key bodies concerned with sharing Earth monitoring data, including the Belmont Forum of funders and other members of the International Science and Technology Alliance for Global Sustainability that has established Future Earth (an international programme for sustainability research), the international committee on Integrated Research on Disaster Risk (IRDR), and GEO. It is from these bodies that funding for the phase II follow-on project of software implementation will be sought.

The two seminars will be a means of creating UK /Chinese collaboration to test the outcome and to ensure that the emerging standard meets the needs of both countries and so that Earth Observation data can be shared seamlessly. In this way, the UK-China collaboration will be pivotal in setting the world standard and the future direction in sharing Earth Observation data on the Web. The collaboration will greatly increase the integrity of the work and take it to the point where it can be implemented and its recommendations tested.


The CEO-LD project is open to organisations in the UK and China with an interest in developing methods for sharing and maximising the re-use of Earth Observation data. Initial stakeholders include:

In China
Institute of Remote Sensing and Digital Earth (RADI) of the Chinese Academy of Sciences.
Beihang University, the China host of W3C
In the UK
The Satellite Applications Catapult
The UK Met Office
Sir Martin Sweeting, chair of Surrey Satellite Systems Ltd and DCMii, and director of the Surrey Space Centre.
Markup Systems Ltd (for W3C)
The Open geospatial Consortium (OGC).
Ed Parsons, Google

The set up of the W3C/OGC Working Group is itself unusual. Formally there are two WGs, one each for the two SDOs. Details are given in the charter.