AQ Community Metadata Discussion

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• Sample ISO Metadata Records
• AQ Community Fields
• Airbase v5 Metadata descriptions Media:Airbase_Metadata_Example.xls and Media:AirBase_IT_v5_xmldata.zip

Remember: the following are facets for finding data!

Dataset

• generally: data from one provider, one (satellite) instrument or one model.
• Need to further clarify granularity for model data. For example: "MACC" or "MACC forecast" and "MACC reanalysis"

Parameter

• relatively clear (= "variable name", "field name" or "layer name")
• issue: same parameter can come in different units (e.g. surface ozone in ug/m3 or ppb) - "units" is a separate facet, so it is possible to make selection if two variants of the same data are on offer
• rerlation to CF standard_name: parameter name should be extract from standard_name describing the physical quantitiy without its representation

Platform

• predefined values: satellite, surface station, sonde, aircraft, model, emission (/!\ CHANGED) -- check common data model; climate community
• Lorenzo: look at evolution of standard where these problems are dealt with (platform and geometry); can we adopt their language

new facet: Geometry or FeatureType

• see also CF featureType; climate science markup language (CSML 3 writeup)
• time series (=point), vertical profile, layer, column, multi-dimensional (=gridded), trajectory

DataType

• unclear

Instrument

• new tag for method should be added
• instrument tag may not be available in some services and will get lost in aggregation
• present agreement on "coarse resolution catalogue" would not allow mapping of intrument and method as it will not go down to the level of individual stations
• use "instrument" also for "modelname" (rename facet to "instrument_modelname"?)

Domain

• remove this facet

Topic Category

• comes from ISO

Time Resolution

• rename to "Sample_Length"
• Tim Dye to sort this out...

new facet: Periodicity

• add "irregular" as value

new facet: revision_status

• trace dataset version: version number? Code "preliminary" and "final"? ...

• describes processing of data along any dimension. See cell_methods attributes in CF convention and follow same syntax. See [1]

Originator

• only lists originator short name

Data Distributor

• only lists distributor short name

Space

• bounding box

resurrect facet: vertical (rename to "vertical_extent"?)

• range with fixed keywords: surface, troposphere, stratosphere, mesosphere, whole atmosphere

Time

• min-max; allows for "now"