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      "licence": "Contains OS data \u00a9 Crown copyright and database right 2026; Open Government Licence"
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      "referencePeriod": "1991-2020",
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      "url": "https://www.arcgis.com/home/item.html?id=4d5f49b8e0de4119a4579444aed5f6a0",
      "licence": "Contains Met Office data licensed under the Open Government Licence v3.0"
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  "frost": "Road-length-weighted 1991\u20132020 air-frost normal, public 2 km HadUK-Grid v1.1.0.0; at least 99% mapped-road coverage required. Not annual weather or carriageway ice."
}
