{
  "id": "2026-10-08-greenland",
  "region": "greenland",
  "status": "published",
  "draftedAt": "2026-10-08",
  "publishedAt": "2026-10-08",
  "dataThrough": "2026-08-31",
  "headline": "Greenland lost ice over the latest annual period.",
  "value": "191",
  "unit": "Gt",
  "valueLabel": "Estimated net ice loss",
  "baselineLabel": "September 2025\u2013August 2026 \u00b7 source uncertainty \u00b198 Gt",
  "copy": "Greenland\u2019s ice sheet lost an estimated 191 billion tonnes over September 2025\u2013August 2026. This is the balance between ice gained and ice lost across the whole ice sheet. The estimate lies within the 1990/91\u20132019/20 historical range, with source uncertainty of \u00b198 billion tonnes. It records a net reduction in land ice, which contributes to sea-level rise; it does not describe the past fortnight.",
  "mapHref": "#ice-overview-title",
  "mapLabel": "Explore the annual ice record",
  "methodsHref": "/data.html#greenland-annual-balance",
  "source": "PROMICE mass balance product (Mankoff et al. 2021)",
  "sourceUrl": "https://doi.org/10.22008/FK2/OHI23Z",
  "licence": "CC BY 4.0",
  "evidence": {
    "annualRecord": {
      "year": 2026,
      "MB": -191.146921,
      "MB_err": 98.316961,
      "SMB": 330.492777,
      "SMB_err": 29.744357,
      "D": 497.663102,
      "D_err": 63.815599,
      "BMB": 23.976572,
      "BMB_err": 5.567392
    },
    "referenceMeanGt": -157.43547519999998,
    "referenceSdGt": 142.38910781598642,
    "rangeLowerGt": -442.2136908319728,
    "rangeUpperGt": 127.34274043197286,
    "periodStart": "2025-09-01",
    "periodEnd": "2026-08-31",
    "retrievedAt": "2026-10-04",
    "providerCsv": "https://thredds.geus.dk/thredds/fileServer/MassBalance/MB_SMB_D_BMB_ann_hydro.csv"
  },
  "selectionReason": "Latest complete annual estimate in the saved PROMICE record. This is an annual context briefing, not a newly detected fortnightly anomaly.",
  "method": {
    "kind": "Estimate from surface-mass-balance models, solid-ice discharge and basal mass balance",
    "limitations": [
      "Annual estimates may be revised.",
      "Source uncertainty is preserved without assigning an unsupported confidence level.",
      "Ice mass balance is distinct from glacier surface speed and sea-ice extent."
    ]
  },
  "sourceSha256": "c50e842b72cd9e991a96966d2aba46351e0630a0253c724a5c157ecc055e2df5",
  "editorialAssessment": {
    "analyse": "The saved PROMICE record estimates net whole-ice-sheet balance of \u2212191.147 Gt over 1 September 2025\u201331 August 2026.",
    "evaluate": "The central estimate lies within the mean plus/minus two sample-standard-deviation range of the 30 annual balances from 1990/91\u20132019/20 (-442.2 to 127.3 Gt). Source uncertainty is \u00b198.317 Gt; no unsupported confidence level is assigned. Within the range does not imply a stable ice sheet.",
    "explain": "Net loss of land ice contributes to sea-level rise. This is an annual balance estimate rather than local melt or glacier speed; we have not calculated a sea-level contribution from this value."
  },
  "reviewedAt": "2026-10-08",
  "contextSourceUrl": "https://science.nasa.gov/earth/explore/earth-indicators/ice-sheets/",
  "archivedInputs": "/briefings/evidence/2026-10-08-greenland-inputs.json",
  "archivedInputsSha256": "c50e842b72cd9e991a96966d2aba46351e0630a0253c724a5c157ecc055e2df5"
}