René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Compliant Checker portential issue: Check requires legacy `branch_time` even though CMIP6 uses `branch_time_in_child` / `branch_time_in_parent`","articleBody":"## Summary\n\n`compliance-checker --test wcrp_cmip6:1.0` reports a MED-priority failure on\nevery CMIP6 file we tested:\n\n```text\nRequired global attribute 'branch_time' is missing.\n```\n\nBut CMIP6 does not require a singular `branch_time` global attribute. The\nrequired CMIP6 attributes for branching are `branch_time_in_child` and\n`branch_time_in_parent`, both of which are present in every failing file. The\nsingular `branch_time` was a CMIP5-era convention.\n\nThis looks like a checker / `esgvoc` registry asserting a legacy attribute,\nproducing a universal false positive on otherwise CMIP6-compliant files.\n\n## Checker Output (verbatim)\n\n```text\n[ATTR001] Global attribute 'branch_time' existence   (weight=2)  value=[0, 1]\n  Required global attribute 'branch_time' is missing.\n```\n\n## What the Files Actually Have\n\nCMIP6-compliant branch attributes are present and well-formed in every file:\n\n```text\n:experiment_id           = \"historical\" ;\n:parent_experiment_id    = \"piControl\" ;\n:parent_activity_id      = \"CMIP\" ;\n:parent_source_id        = \"ACCESS-ESM1-5\" ;\n:parent_variant_label    = \"r1i1p1f1\" ;\n:parent_time_units       = \"days since 0001-01-01 00:00:00\" ;\n:parent_mip_era          = \"CMIP6\" ;\n:branch_time_in_child    = 0. ;\n:branch_time_in_parent   = 0. ;\n:branch_method           = \"standard\" ;\n```\n\nThere is no `branch_time` global attribute — by CMIP6 convention there\nshould not be.","author":{"url":"https://github.com/rhaegar325","@type":"Person","name":"rhaegar325"},"datePublished":"2026-05-29T05:29:49.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":0},"url":"https://github.com/413/ACCESS-MOPPy/issues/413"}