The OGC Observations and Measurements Specification & Applicability to TDWG’s Domain Phillip C. Dibner Ecosystem Associates TDWG Annual Meeting Saint Louis, Missouri October 17, 2006

Context The Observations and Measurements spec provides encoding-neutral foundation classes upon which to build models for observations relevant to a particular domain, like TDWG’s. O&M was developed within the OGC’s Sensor Web Enablement (SWE) “thread” NB: The notion of a Sensor is entirely general. (first versions of O&M included an example of quadrat measurements from a grassland survey) A related spec, SensorML describes “sensors.” A quadrat, transect, or grid of quadrats, points, etc. would qualify… Notion of process or procedure for conducting the measurement is fundamental. (In fact there’s talk of calling it “ProcedureML,” but Sensor is too strong a “brand” to abandon…)

History Objects and Measurements first version developed in original OWS initiative - ~ Developed in the context of the OGC’s Web Services (OWS) initiatives Current public draft from OWS-3, completed in April, 2005 and undergoing further refinement in OWS-4 Foundational notions come from Martin Fowler, 1998, Analysis Patterns: reusable object models (Addison Wesley Longman, Menlo Park), metrology, and a variety of scientific disciplines Bottom line: well reviewed, mature and open for further refinement!

How Does It Relate to TDWG? Take TDWG Observation Group notions and apply them to the O&M model. There is a process for this. In brief: - Decide what doesn’t go in the domain of interest and belongs in someone else’s. - Identify the common elements that everyone agrees on, and that all implementations will include. … as the TDWG Observations Group have already substantially done! - These form the basis of a Conceptual Model There is an emerging spec, the Sensor Observation Service (SOS), that serves Observations. If we serve our data as Observations, they will be broadly accessible. For more detail: we will discuss in the Geospatial Interest Group, Wednesday, 11:15 AM.