{"finding":{"findingId":"01a0e1f1-2bce-79d7-8daf-fd43ca7561fe","status":"published","tier":1,"rule":{"name":"indicator_trend","version":"1.0","params":{"indicator":"tree-cover-loss"}},"title":"Tree cover loss rose to 29.6 million (ha/yr) in 2024 — the world keeps losing tree cover faster","summary":"Tree cover loss rose to 29.6 million (ha/yr) in 2024, from 28.2 million in 2023 (+4.7%). Over the last ten years of data it is worsening (+11.9% per decade). Source: Global Forest Watch (Hansen / UMD), via Our World in Data. A later read showing the same value confirms the source has not revised it.","geometry":{"type":"Polygon","coordinates":[[[-180,-90],[180,-90],[180,90],[-180,90],[-180,-90]]]},"bbox":[-180,-90,180,90],"aoi":{"id":"wp-tree-cover-loss","name":"World: tree cover loss","tags":["world-indicator","worsening"]},"context":{"enso":{"phase":"El Niño","oni":1.8},"events":[{"id":"EONET_24811","title":"Tropical Storm Gonzalo","category":"Severe Storms"},{"id":"EONET_6510","title":"Iceberg D33C","category":"Sea and Lake Ice"},{"id":"EONET_24786","title":"Hurricane Nolo","category":"Severe Storms"},{"id":"EONET_24787","title":"Typhoon Surigae","category":"Severe Storms"},{"id":"EONET_24809","title":"Wildfire Merit Creek, Greene, Mississippi","category":"Wildfires"},{"id":"EONET_24785","title":"Tropical Cyclone 01B","category":"Severe Storms"},{"id":"EONET_24721","title":"Hurricane Polo","category":"Severe Storms"},{"id":"EONET_24710","title":"Wildfire Round Prarie, Morehouse, Louisiana","category":"Wildfires"},{"id":"EONET_24722","title":"Tropical Storm Fay","category":"Severe Storms"},{"id":"EONET_24720","title":"Hurricane Odalys","category":"Severe Storms"},{"id":"EONET_24810","title":"Prescribed Fire CRAWFORD CORRAL RX, Tulare, California","category":"Wildfires"},{"id":"EONET_6523","title":"Iceberg A83","category":"Sea and Lake Ice"},{"id":"EONET_10212","title":"Iceberg B22F","category":"Sea and Lake Ice"},{"id":"EONET_24719","title":"Prescribed Fire D2 Dye RX, Coconino, Arizona","category":"Wildfires"},{"id":"EONET_24718","title":"Prescribed Fire D2 Vincent RX, Coconino, Arizona","category":"Wildfires"},{"id":"EONET_24483","title":"Wildfire Breezy, Starr, Texas","category":"Wildfires"},{"id":"EONET_24488","title":"Wildfire FLORISTON, Nevada, California","category":"Wildfires"},{"id":"EONET_24317","title":"Typhoon Dujuan","category":"Severe Storms"},{"id":"EONET_24499","title":"Prescribed Fire RX CALV BU 104-108, Vernon, Louisiana","category":"Wildfires"},{"id":"EONET_24482","title":"Wildfire Clark, Edwards, Texas","category":"Wildfires"}],"notes":["Dataset: Global Forest Watch (Hansen / UMD) via Our World in Data (grapher tree-cover-loss); annual series, direction = 10-year linear trend."]},"blindSpots":["Annual global indicators lag reality by 1–5 years: a 'new' value can describe a year long past.","The direction is the 10-year trend, not the single year: one year can move against the trend, and the title then says so.","Global aggregates hide where it happens — a stable global number can mask collapse in one region and recovery in another.","Confirmation only proves the source did not revise the number on a later read — same provider, not an independent measurement.","Some series are single sites (ocean pH is Station ALOHA, Hawaii) or modelled composites (Living Planet Index) with wide uncertainty bands we do not show.","Upstream methods change between releases; a revised back-series can make a year look new or change the trend."],"observedAt":"2024-01-01T00:00:00Z","createdAt":"2026-09-27T08:16:26.160Z","updatedAt":"2026-09-30T01:23:40.499Z","createdBy":"system:indicator_trend@1.0","confirmed":{"at":"2026-09-27T13:40:21.136Z","independence":"method","signal":{"id":"owid-tree-cover-loss-2024-reread-2026-09-27","kind":"series","source":"owid-grapher","collection":"tree-cover-loss","datetime":"2024-01-01T00:00:00Z","href":"https://ourworldindata.org/grapher/tree-cover-loss","method":{"name":"indicator_trend","version":"1.0","params":{"indicator":"tree-cover-loss","retrievedAt":"2026-09-27T13:40:21.136Z"}},"summary":"Re-read on 2026-09-27: 2024 value unchanged at 29559676 — the source has not revised it. Same provider (data stability, not an independent measurement).","values":{"value":29559676,"year":2024}}},"evidence":[{"id":"owid-tree-cover-loss-2024","kind":"series","source":"owid-grapher","collection":"tree-cover-loss","datetime":"2024-01-01T00:00:00Z","href":"https://ourworldindata.org/grapher/tree-cover-loss","method":{"name":"indicator_trend","version":"1.0","params":{"indicator":"tree-cover-loss","retrievedAt":"2026-09-27T08:16:26.160Z"}},"summary":"Tree cover loss: 2024 = 29559676 (2023 = 28231408) ha/yr; 10-year trend 11.9% per decade (worsening). Upstream: Global Forest Watch (Hansen / UMD).","values":{"changePct":4.7,"pctPerDecade":11.9,"previous":28231408,"value":29559676,"year":2024}}],"attribution":null,"narration":{"v":1,"eventId":"01a0efe8-f565-7798-8aa1-bd8495f86500","findingId":"01a0e1f1-2bce-79d7-8daf-fd43ca7561fe","at":"2026-09-30T01:23:36.933Z","actor":"model:claude-opus-5","prev":"acd11b0cab21154b1de017bf55cfff54c41b18727e09d7da5fd47c47ca5d0309","kind":"narrated","text":"Global tree cover loss hit 29.6 million hectares in 2024, up 4.7% on 2023\n\nGlobal Forest Watch data (Hansen/UMD), published via Our World in Data, records 29,559,676 hectares of tree cover lost worldwide in 2024, up from 28,231,408 hectares in 2023 — a rise of 4.7%. Across the last ten years of data the series is worsening by 11.9% per decade. A re-read of the same source on 27 September 2026 returned the identical 2024 value, showing the figure has not been revised; that is a stability check by the same provider, not an independent measurement.\n\nWhat this is not: \"tree cover loss\" is not the same as deforestation or clearing. It counts canopy disappearing for any reason — fire, storm damage, disease, drought stress, logging rotations and replanting cycles all register. 2024 sits in an El Niño phase (ONI 1.8), which tends to bring hotter, drier conditions and more fire in forested regions, and the period's event log includes multiple wildfires and tropical storms. A global total also hides geography: it can mask sharp losses in one region and regrowth in another.\n\nWhat would change our mind: a revised back-series or changed upstream method, or regional breakdowns showing the rise is dominated by fire and storm years rather than a sustained trend.\n\nKey numbers:\n- Tree cover loss, 2024 (ha/yr): 29559676 [owid-tree-cover-loss-2024]\n- Tree cover loss, 2023 (ha/yr): 28231408 [owid-tree-cover-loss-2024]\n- Year-on-year change (%): 4.7 [owid-tree-cover-loss-2024]\n- 10-year trend (% per decade): 11.9 [owid-tree-cover-loss-2024]\n- Re-read value, unchanged (ha/yr): 29559676 [owid-tree-cover-loss-2024-reread-2026-09-27]\n\nConfidence: medium\nCaveats:\n- Tree cover loss includes fire, storm and disease damage as well as clearing; it is not a deforestation count.\n- Annual global indicators can lag reality by 1–5 years.\n- The confirming read is the same provider, so it only shows the number was not revised.\n- El Niño (ONI 1.8) and an active fire and storm season can lift loss in a single year.\n- A global total can hide regional collapse or regional recovery.\n- Upstream method changes or a revised back-series could shift both the 2024 value and the trend.","model":{"id":"claude-opus-5","provider":"anthropic"},"promptSha256":"ce18d4d8791831253be568cdaf582e0d188ff40bb02ddc7c89167f12df0cc4c6","transcriptSha256":"ed1edd4e9afe21ec383d1a3b3926b5ff17a42a69392e6e07b1ff0aba3c302715","evidenceRefs":["owid-tree-cover-loss-2024","owid-tree-cover-loss-2024-reread-2026-09-27"]},"reviews":[{"v":1,"eventId":"01a0efe9-034a-7961-a7dd-01c3e221cbf7","findingId":"01a0e1f1-2bce-79d7-8daf-fd43ca7561fe","at":"2026-09-30T01:23:40.490Z","actor":"model:claude-sonnet-5","prev":"9d446e9b3b1b0ffe56517b48fa2e5250cca4aa2e3bfc5803204e4c9faef8a3d0","kind":"reviewed","decision":"approve","tier":1,"note":"All figures (29,559,676; 28,231,408; 4.7%; 11.9% per decade; reread value) match evidence exactly; Narration correctly caveats that tree cover loss is not deforestation, notes El Niño/wildfire/storm context, lag issues, same-provider re-read limitation, and regional aggregation blind spot; No individuals are named; AOI is world-indicator/worsening, not tagged control, consistent with a global monitoring finding rather than a control check","verdict":"publish"}],"notifications":[],"replies":[],"retracted":null,"history":[{"at":"2026-09-27T08:16:26.160Z","kind":"created","status":"candidate","actor":"system:indicator_trend@1.0"},{"at":"2026-09-27T13:40:21.136Z","kind":"confirmed","status":"confirmed","actor":"system:indicator_trend@1.0"},{"at":"2026-09-30T01:23:36.933Z","kind":"narrated","status":"confirmed","actor":"model:claude-opus-5"},{"at":"2026-09-30T01:23:40.490Z","kind":"reviewed","status":"confirmed","actor":"model:claude-sonnet-5"},{"at":"2026-09-30T01:23:40.499Z","kind":"status_changed","status":"published","actor":"model:claude-sonnet-5"}],"eventCount":5,"lastEventHash":"0a00d3df59733bf36b80a192ace8bcbe96de1a683551b0c753ce809be77fcb18"},"events":[{"v":1,"eventId":"01a0e1f1-2bce-7c55-8947-ed6a0be8fa27","findingId":"01a0e1f1-2bce-79d7-8daf-fd43ca7561fe","at":"2026-09-27T08:16:26.160Z","actor":"system:indicator_trend@1.0","prev":null,"kind":"created","rule":{"name":"indicator_trend","version":"1.0","params":{"indicator":"tree-cover-loss"}},"title":"Tree cover loss rose to 29.6 million (ha/yr) in 2024 — the world keeps losing tree cover faster","summary":"Tree cover loss rose to 29.6 million (ha/yr) in 2024, from 28.2 million in 2023 (+4.7%). Over the last ten years of data it is worsening (+11.9% per decade). Source: Global Forest Watch (Hansen / UMD), via Our World in Data. A later read showing the same value confirms the source has not revised it.","tier":1,"geometry":{"type":"Polygon","coordinates":[[[-180,-90],[180,-90],[180,90],[-180,90],[-180,-90]]]},"bbox":[-180,-90,180,90],"aoi":{"id":"wp-tree-cover-loss","name":"World: tree cover loss","tags":["world-indicator","worsening"]},"observedAt":"2024-01-01T00:00:00Z","evidence":[{"id":"owid-tree-cover-loss-2024","kind":"series","source":"owid-grapher","collection":"tree-cover-loss","datetime":"2024-01-01T00:00:00Z","href":"https://ourworldindata.org/grapher/tree-cover-loss","method":{"name":"indicator_trend","version":"1.0","params":{"indicator":"tree-cover-loss","retrievedAt":"2026-09-27T08:16:26.160Z"}},"summary":"Tree cover loss: 2024 = 29559676 (2023 = 28231408) ha/yr; 10-year trend 11.9% per decade (worsening). Upstream: Global Forest Watch (Hansen / UMD).","values":{"changePct":4.7,"pctPerDecade":11.9,"previous":28231408,"value":29559676,"year":2024}}],"context":{"enso":{"phase":"El Niño","oni":1.8},"events":[{"id":"EONET_24811","title":"Tropical Storm Gonzalo","category":"Severe Storms"},{"id":"EONET_6510","title":"Iceberg D33C","category":"Sea and Lake Ice"},{"id":"EONET_24786","title":"Hurricane Nolo","category":"Severe Storms"},{"id":"EONET_24787","title":"Typhoon Surigae","category":"Severe Storms"},{"id":"EONET_24809","title":"Wildfire Merit Creek, Greene, Mississippi","category":"Wildfires"},{"id":"EONET_24785","title":"Tropical Cyclone 01B","category":"Severe Storms"},{"id":"EONET_24721","title":"Hurricane Polo","category":"Severe Storms"},{"id":"EONET_24710","title":"Wildfire Round Prarie, Morehouse, Louisiana","category":"Wildfires"},{"id":"EONET_24722","title":"Tropical Storm Fay","category":"Severe Storms"},{"id":"EONET_24720","title":"Hurricane Odalys","category":"Severe Storms"},{"id":"EONET_24810","title":"Prescribed Fire CRAWFORD CORRAL RX, Tulare, California","category":"Wildfires"},{"id":"EONET_6523","title":"Iceberg A83","category":"Sea and Lake Ice"},{"id":"EONET_10212","title":"Iceberg B22F","category":"Sea and Lake Ice"},{"id":"EONET_24719","title":"Prescribed Fire D2 Dye RX, Coconino, Arizona","category":"Wildfires"},{"id":"EONET_24718","title":"Prescribed Fire D2 Vincent RX, Coconino, Arizona","category":"Wildfires"},{"id":"EONET_24483","title":"Wildfire Breezy, Starr, Texas","category":"Wildfires"},{"id":"EONET_24488","title":"Wildfire FLORISTON, Nevada, California","category":"Wildfires"},{"id":"EONET_24317","title":"Typhoon Dujuan","category":"Severe Storms"},{"id":"EONET_24499","title":"Prescribed Fire RX CALV BU 104-108, Vernon, Louisiana","category":"Wildfires"},{"id":"EONET_24482","title":"Wildfire Clark, Edwards, Texas","category":"Wildfires"}],"notes":["Dataset: Global Forest Watch (Hansen / UMD) via Our World in Data (grapher tree-cover-loss); annual series, direction = 10-year linear trend."]},"blindSpots":["Annual global indicators lag reality by 1–5 years: a 'new' value can describe a year long past.","The direction is the 10-year trend, not the single year: one year can move against the trend, and the title then says so.","Global aggregates hide where it happens — a stable global number can mask collapse in one region and recovery in another.","Confirmation only proves the source did not revise the number on a later read — same provider, not an independent measurement.","Some series are single sites (ocean pH is Station ALOHA, Hawaii) or modelled composites (Living Planet Index) with wide uncertainty bands we do not show.","Upstream methods change between releases; a revised back-series can make a year look new or change the trend."]},{"v":1,"eventId":"01a0e31a-b25d-7759-9e66-1f20be5b8a51","findingId":"01a0e1f1-2bce-79d7-8daf-fd43ca7561fe","at":"2026-09-27T13:40:21.136Z","actor":"system:indicator_trend@1.0","prev":"08b8aecb26aaae54daeed8dbd8c15e99c9995316762f360bf10f0313c08cf9e5","kind":"confirmed","signal":{"id":"owid-tree-cover-loss-2024-reread-2026-09-27","kind":"series","source":"owid-grapher","collection":"tree-cover-loss","datetime":"2024-01-01T00:00:00Z","href":"https://ourworldindata.org/grapher/tree-cover-loss","method":{"name":"indicator_trend","version":"1.0","params":{"indicator":"tree-cover-loss","retrievedAt":"2026-09-27T13:40:21.136Z"}},"summary":"Re-read on 2026-09-27: 2024 value unchanged at 29559676 — the source has not revised it. Same provider (data stability, not an independent measurement).","values":{"value":29559676,"year":2024}},"independence":"method"},{"v":1,"eventId":"01a0efe8-f565-7798-8aa1-bd8495f86500","findingId":"01a0e1f1-2bce-79d7-8daf-fd43ca7561fe","at":"2026-09-30T01:23:36.933Z","actor":"model:claude-opus-5","prev":"acd11b0cab21154b1de017bf55cfff54c41b18727e09d7da5fd47c47ca5d0309","kind":"narrated","text":"Global tree cover loss hit 29.6 million hectares in 2024, up 4.7% on 2023\n\nGlobal Forest Watch data (Hansen/UMD), published via Our World in Data, records 29,559,676 hectares of tree cover lost worldwide in 2024, up from 28,231,408 hectares in 2023 — a rise of 4.7%. Across the last ten years of data the series is worsening by 11.9% per decade. A re-read of the same source on 27 September 2026 returned the identical 2024 value, showing the figure has not been revised; that is a stability check by the same provider, not an independent measurement.\n\nWhat this is not: \"tree cover loss\" is not the same as deforestation or clearing. It counts canopy disappearing for any reason — fire, storm damage, disease, drought stress, logging rotations and replanting cycles all register. 2024 sits in an El Niño phase (ONI 1.8), which tends to bring hotter, drier conditions and more fire in forested regions, and the period's event log includes multiple wildfires and tropical storms. A global total also hides geography: it can mask sharp losses in one region and regrowth in another.\n\nWhat would change our mind: a revised back-series or changed upstream method, or regional breakdowns showing the rise is dominated by fire and storm years rather than a sustained trend.\n\nKey numbers:\n- Tree cover loss, 2024 (ha/yr): 29559676 [owid-tree-cover-loss-2024]\n- Tree cover loss, 2023 (ha/yr): 28231408 [owid-tree-cover-loss-2024]\n- Year-on-year change (%): 4.7 [owid-tree-cover-loss-2024]\n- 10-year trend (% per decade): 11.9 [owid-tree-cover-loss-2024]\n- Re-read value, unchanged (ha/yr): 29559676 [owid-tree-cover-loss-2024-reread-2026-09-27]\n\nConfidence: medium\nCaveats:\n- Tree cover loss includes fire, storm and disease damage as well as clearing; it is not a deforestation count.\n- Annual global indicators can lag reality by 1–5 years.\n- The confirming read is the same provider, so it only shows the number was not revised.\n- El Niño (ONI 1.8) and an active fire and storm season can lift loss in a single year.\n- A global total can hide regional collapse or regional recovery.\n- Upstream method changes or a revised back-series could shift both the 2024 value and the trend.","model":{"id":"claude-opus-5","provider":"anthropic"},"promptSha256":"ce18d4d8791831253be568cdaf582e0d188ff40bb02ddc7c89167f12df0cc4c6","transcriptSha256":"ed1edd4e9afe21ec383d1a3b3926b5ff17a42a69392e6e07b1ff0aba3c302715","evidenceRefs":["owid-tree-cover-loss-2024","owid-tree-cover-loss-2024-reread-2026-09-27"]},{"v":1,"eventId":"01a0efe9-034a-7961-a7dd-01c3e221cbf7","findingId":"01a0e1f1-2bce-79d7-8daf-fd43ca7561fe","at":"2026-09-30T01:23:40.490Z","actor":"model:claude-sonnet-5","prev":"9d446e9b3b1b0ffe56517b48fa2e5250cca4aa2e3bfc5803204e4c9faef8a3d0","kind":"reviewed","decision":"approve","tier":1,"note":"All figures (29,559,676; 28,231,408; 4.7%; 11.9% per decade; reread value) match evidence exactly; Narration correctly caveats that tree cover loss is not deforestation, notes El Niño/wildfire/storm context, lag issues, same-provider re-read limitation, and regional aggregation blind spot; No individuals are named; AOI is world-indicator/worsening, not tagged control, consistent with a global monitoring finding rather than a control check","verdict":"publish"},{"v":1,"eventId":"01a0efe9-0353-77ca-9e40-a4a06b0d0fd6","findingId":"01a0e1f1-2bce-79d7-8daf-fd43ca7561fe","at":"2026-09-30T01:23:40.499Z","actor":"model:claude-sonnet-5","prev":"c7aafe79e0d75aa665cb70e69305162897d8bd538e48a0863c79e4c558f07e48","kind":"status_changed","from":"confirmed","to":"published","reason":"autonomous publish: narrated by model:claude-opus-5, reviewed by model:claude-sonnet-5 (policy 2026-09-26-autonomous)","gates":{"narratedBy":"model:claude-opus-5","reviewedBy":["model:claude-sonnet-5"],"policy":"2026-09-26-autonomous"}}],"inclusion":{"index":958,"leafHash":"357e4ab9d709c270d5434f05bb6dae450f4ba477d4e5804e79c65b9a8421366c","proof":["69f11d06fd289dbbf0e1464a5b0a4b96f87169b58925628491c8f009af6d40ca","2ca7f81108e118aeb27202a67d471ce627e18e644fd268e646cc95ff41aa228f","519e40571fe97e6bc4744a71a0ddc3ed2418eeaedc637ac2fd698d5218cebb73","dd2c9fe6ae688c5475aff3e46cbdfeaf464df870ad3a941c7f428943a0ab02f3","0045955efc1ce8cbac08a8733861af830ac685c100ede195c387e074963da34e","881a017e2581f97da1c46804177dfd5f924565433e1166705255b96348abe25d","a72c3339b408a45e95e937a87116707abc006bf01b9d03fe3f1a13fbcc11992a","d4a69eb9bd4aba2b04a0c06f8365d5c370a5591fa80d0e8a9962a94eea222b01","b151de5eaefddf3d1cfc86f94cdbc3995ed5d406a6c0acfc99649a5d48d50794","5f7580b7f5a7f09ff7675565fb36c19876079a6c101f721419a5a07a7a23b1c1"],"size":971,"root":"65becba35e7b7adb50a8f9aed2d9bcf019d64a4302dd924c1051516e6bcfb1ac"}}