{
  "schemaVersion": "climate-polar-source/v1",
  "version": "Sea Ice Index v4",
  "snapshot": "v4-2026-09-11",
  "datasetId": "G02135",
  "doi": "10.7265/A98X-0F50",
  "publisher": "NOAA / National Snow and Ice Data Center",
  "landing": "https://nsidc.org/data/g02135/versions/4",
  "rights": "https://nsidc.org/about/data-use-and-copyright",
  "rightsNote": "Reuse with dataset citation and NSIDC attribution; source-product identifiers retained.",
  "retrievedAt": "2026-09-11T07:15:08.414Z",
  "files": [
    {
      "region": "N",
      "month": 1,
      "filename": "N_01_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/north/monthly/data/N_01_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "61938dffac6f610d1d9610f70e8fb54fd14dfa93eaeec4047fd6ad13cbe2628f"
    },
    {
      "region": "N",
      "month": 2,
      "filename": "N_02_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/north/monthly/data/N_02_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "cf1df2e3730acdc39831c386fc4c5ae765fc0d661f7466290e9239490422b32e"
    },
    {
      "region": "N",
      "month": 3,
      "filename": "N_03_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/north/monthly/data/N_03_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "01c4fa25d1a4a35aee9558eeecd652564fc91582e35e7b2fcaf8c19ebf56aff7"
    },
    {
      "region": "N",
      "month": 4,
      "filename": "N_04_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/north/monthly/data/N_04_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "31ededc3210d6b30dce1ac5c3bf1009d8ab8faee75d1cdf6a9ff39dcc7fe6e94"
    },
    {
      "region": "N",
      "month": 5,
      "filename": "N_05_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/north/monthly/data/N_05_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "143786739a6f3d5d1a3208fa61f299a4afdff142974dfc973bfd1ee86670dc72"
    },
    {
      "region": "N",
      "month": 6,
      "filename": "N_06_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/north/monthly/data/N_06_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "33f08540d96b62554ebcd8e27030364815be3e0836d03453e9bb078ef4452d0f"
    },
    {
      "region": "N",
      "month": 7,
      "filename": "N_07_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/north/monthly/data/N_07_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "0be2b36d07f5eb3ec2ddb7a8604fcdf508ef718254ae3795c655681b3e567bf4"
    },
    {
      "region": "N",
      "month": 8,
      "filename": "N_08_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/north/monthly/data/N_08_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "099dfed84622912b5dc11d56acfa81193788e0d81a2e751ebeecb16ddb1de504"
    },
    {
      "region": "N",
      "month": 9,
      "filename": "N_09_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/north/monthly/data/N_09_extent_v4.0.csv",
      "bytes": 2304,
      "sha256": "bdeb4dea8b52f6dc8a8faecfd5d220dc758b6dd2ddea345d7b18897df0d9716f"
    },
    {
      "region": "N",
      "month": 10,
      "filename": "N_10_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/north/monthly/data/N_10_extent_v4.0.csv",
      "bytes": 2304,
      "sha256": "5b54b8bab1785d704c78a59d0df03171f4c9fccb88438d56b28e4c2befe2c150"
    },
    {
      "region": "N",
      "month": 11,
      "filename": "N_11_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/north/monthly/data/N_11_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "2e883fcb0968770e2e6e02147e7004b75d9f937dbea353a78a60cb19aaa626ea"
    },
    {
      "region": "N",
      "month": 12,
      "filename": "N_12_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/north/monthly/data/N_12_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "4bda9d85fd7212bb847dea3a19a5e6a28aa65bb6e38db6a586a88251049ffc94"
    },
    {
      "region": "S",
      "month": 1,
      "filename": "S_01_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/south/monthly/data/S_01_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "ab782f15f3fb878f5c668e29095f200790ca5fa73805508b4ee78a273e3a0a86"
    },
    {
      "region": "S",
      "month": 2,
      "filename": "S_02_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/south/monthly/data/S_02_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "ee9717d02fbc7f5ad66fb6982d3a5cb746c02a011311f2419f1483384ce9f8b3"
    },
    {
      "region": "S",
      "month": 3,
      "filename": "S_03_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/south/monthly/data/S_03_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "569eb0d2eeb49ffb195d623476998aab9d5b0d3f4b9657a34bef7a818556c92f"
    },
    {
      "region": "S",
      "month": 4,
      "filename": "S_04_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/south/monthly/data/S_04_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "0970d41942ff99a4bc15cfba95d7e4ed944db774e9fd79ecbc0af4e7a98d2139"
    },
    {
      "region": "S",
      "month": 5,
      "filename": "S_05_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/south/monthly/data/S_05_extent_v4.0.csv",
      "bytes": 2361,
      "sha256": "65bee706e7aabae72e1fc9c8bc37ad21009d1415ff7a49002dab469e2c9b3555"
    },
    {
      "region": "S",
      "month": 6,
      "filename": "S_06_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/south/monthly/data/S_06_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "ccbe22a3b01f37d48405a6f7898fc63fde30e740f45d29d775f526b5ce875b1e"
    },
    {
      "region": "S",
      "month": 7,
      "filename": "S_07_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/south/monthly/data/S_07_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "eabbacf263faf23a01b8db13252a798485a8a5ef4294a6fbdae5aa0c9af9b527"
    },
    {
      "region": "S",
      "month": 8,
      "filename": "S_08_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/south/monthly/data/S_08_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "64c76142efc35e76f8e593d90e958621cee9ca0a104d3b337494deb3dbcdc2e8"
    },
    {
      "region": "S",
      "month": 9,
      "filename": "S_09_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/south/monthly/data/S_09_extent_v4.0.csv",
      "bytes": 2304,
      "sha256": "b3144d6e841eac3e6320d2037c3d34db0054795b93836c77de715b19c113af7a"
    },
    {
      "region": "S",
      "month": 10,
      "filename": "S_10_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/south/monthly/data/S_10_extent_v4.0.csv",
      "bytes": 2304,
      "sha256": "c2c343b117cb1e04c8f08821ee9982c124312d3cce59c86e90f0a75b6ee8af4e"
    },
    {
      "region": "S",
      "month": 11,
      "filename": "S_11_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/south/monthly/data/S_11_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "1ad02149c0e754021fb136324550bcb171390805e34ea0501b8136874f1f4e5a"
    },
    {
      "region": "S",
      "month": 12,
      "filename": "S_12_extent_v4.0.csv",
      "url": "https://noaadata.apps.nsidc.org/NOAA/G02135/south/monthly/data/S_12_extent_v4.0.csv",
      "bytes": 2352,
      "sha256": "dafcb0df80ac1fb828ae66bb40f28b10539ace084b0a9fb2e19cef145abe1dc2"
    }
  ]
}