CMIP6 Extension Specification

• Title: cmip6
• Identifier: https://stac-extensions.github.io/cmip6/v1.0.0/schema.json
• Field Name Prefix: cmip6
• Scope: Item, Collection, Asset
• Extension Maturity Classification: Proposal
• Owner: @TomAugspurger

This document explains the CMIP6 Extension to the SpatioTemporal Asset Catalog (STAC) specification.

This extensions defines how to encode metadata using the CMIP6 Controlled Vocabulary in STAC.

When specified in Item properties, the values are assumed to apply to all Assets in that Item.

• Examples:
  • Item example: Shows the basic usage of the extension in a STAC Item
  • Collection example: Shows the basic usage of the extension in a STAC Collection
• JSON Schema
• Changelog

Item Properties and Collection Fields

These are the required global attributes. See CMIP6 Global Attributes, DRS, Filenames, Directory Structure, and CV's for more.

Field Name	Type	Description
cmip6:Conventions	string	convention version
cmip6:activity_id	string	activity identifier(s) (part of DRS)
cmip6:creation_date	string	date file was created
cmip6:data_specs_version	string	version identifier
cmip6:experiment	string	short experiment description
cmip6:experiment_id	string	root experiment identifier (part of DRS)
cmip6:forcing_index	number	index for variant of forcing
cmip6:frequency	string	sampling frequency
cmip6:further_info_url	string	location of documentation
cmip6:grid	string	grid
cmip6:grid_label	string	grid identifier (part of DRS)
cmip6:initialization_index	number	Index for variant of initialization method
cmip6:institution	string	institution name
cmip6:institution_id	string	institution identifier (part of DRS)
cmip6:license	string	license restrictions
cmip6:mip_era	string	activity's associated CMIP cycle (part of DRS)
cmip6:nominal_resolution	string	approximate horizontal resolution
cmip6:physics_index	number	index for model physics variant
cmip6:product	string	product type (part of DRS)
cmip6:realization_index	number	realization number
cmip6:realm	string	realm(s) where variable is defined (part of DRS)
cmip6:source	string	full model name / version
cmip6:source_id	string	model identifier (part of DRS)
cmip6:source_type	string	model configuration
cmip6:sub_experiment	string	description of sub-experiment
cmip6:sub_experiment_id	string	sub-experiment identifier (part of DRS "member_id")
cmip6:table_id	string	table identifier (part of DRS)
cmip6:tracking_id	string	unique file identifier
cmip6:variable_id	string	variable identifier (part of DRS)
cmip6:variant_label	string	"variant" label (part of DRS "member_id")

Additional Field Information

Contributing

All contributions are subject to the STAC Specification Code of Conduct. For contributions, please follow the STAC specification contributing guide Instructions for running tests are copied here for convenience.

Running tests

The same checks that run as checks on PR's are part of the repository and can be run locally to verify that changes are valid. To run tests locally, you'll need npm, which is a standard part of any node.js installation.

First you'll need to install everything with npm once. Just navigate to the root of this repository and on your command line run:

npm install

Then to check markdown formatting and test the examples against the JSON schema, you can run:

npm test

This will spit out the same texts that you see online, and you can then go and fix your markdown or examples.

If the tests reveal formatting problems with the examples, you can fix them with:

npm run format-examples