IMBIE 2026 — Greenland and Antarctic ice-sheet loss, 1979–2023: 84% linked to ice dynamics
The IMBIE study in Scientific Data finds Greenland and Antarctica lost 11,309 ± 565 billion tonnes of ice in 1979–2023; glacier dynamical imbalance drove 84% and reduced surface mass balance 16%.
Ice loss is not solely surface melting
The intuitive picture of polar ice loss is warm air melting ice at the surface. The paper splits the 1979–2023 loss into two components: "Increased glacier dynamical imbalance drove 84% of the ice sheets mass loss and reduced SMB the remainder (16%)." Surface mass balance (SMB) is the net of snowfall gains and surface losses, so the 16% is not the same thing as surface melt alone. ESA's article puts it more simply: "84% of the combined ice loss resulted from glaciers accelerating and discharging more ice into the ocean, while just 16% was caused by melting at the surface of the ice sheets."[1][2]
Inès Otosaka of Northumbria University, who led the study, is quoted by ESA: "More than four-fifths of the ice lost was discharged into the ocean by faster-flowing glaciers, rather than melted at the surface – which tells us the long-term trend is being driven by the dynamic response of the ice sheets to a warming ocean."[1]
The totals
The paper reports that Antarctica and Greenland lost 11,309 ± 565 Gt of ice between 1979 and 2023, raising the global sea level by 31.4 ± 1.6 mm. ESA rounds this to 11.3 trillion tonnes and 3.14 centimetres, and headlines it as "a staggering 11 trillion tonnes of ice since the 1970s".[1][2]
Split by ice sheet, ESA says Greenland accounted for 1.81 centimetres of the sea-level rise, compared with 1.33 centimetres from Antarctica. The paper gives Greenland's loss as 6,215 ± 467 Gt over 1972–2023 and Antarctica's as 4,780 ± 513 Gt over 1979–2023. Greenland contributed more.[1][2]
ESA adds that "Together, Greenland and Antarctica are now responsible for around a quarter of global sea-level rise." That leaves roughly three-quarters from other sources — an approximate inference from ESA's wording, not a measured share, and the article does not list those sources.[1]
How far back the record goes
The record "goes back to 1972 for Greenland and 1979 for Antarctica." Otosaka frames the significance as reach: "By reaching back to the 1970s, we can now see how the ice sheets have changed across half a century."[1][2]
Greenland's own record starts in 1972, seven years before Antarctica's, but the combined total and the 84% and 16% shares on this page all refer to the same period, 1979–2023.[2]
Who produced it
The results come from the Ice Sheet Mass Balance Intercomparison Exercise (IMBIE), which ESA describes as "a large international collaboration involving polar scientists from institutes around the world", supported by ESA and NASA. The paper says it compares and combines 42 independent estimates of ice-sheet mass balance.[1][2]
Andrew Shepherd, also of Northumbria University and founder of IMBIE, is quoted by ESA: "Just over three centimetres of sea-level rise may sound small, but that puts another six to nine million people at risk of coastal flooding and erosion."[1]
IMBIE reconciles many separate measurement efforts, so its numbers are a combined estimate across teams, not one instrument's reading.[2]
About the sourcing
The figures on this page come from the paper in Scientific Data and from ESA's article about it. ESA supports IMBIE, so its article is not an independent check on the study; the paper is the authors' own record of the results.[1][2]
Verified facts
Each fact is labelled with its evidence typeEach fact in this section carries its evidence type — either cross-checked against independent sources, or confirmed from a single authoritative record.
Combined, Antarctica and Greenland lost 11,309 ± 565 Gt of ice between 1979 and 2023, raising global sea level by 31.4 ± 1.6 mm; ESA rounds this to 11.3 trillion tonnes and 3.14 centimetres.[1][2] 1 source · authoritative record
Increased glacier dynamical imbalance drove 84% of the ice sheets' mass loss over 1979–2023 and reduced surface mass balance the remainder (16%).[1][2] 1 source · authoritative record
The reconciled record starts in 1972 for Greenland and 1979 for Antarctica and runs to 2023, combining 42 independent estimates of ice-sheet mass balance.[1][2] 1 source · authoritative record
Greenland lost 6,215 ± 467 Gt between 1972 and 2023 and Antarctica 4,780 ± 513 Gt between 1979 and 2023.[2] 1 source · authoritative record
Statements and readings
Not counted as facts — each item shows what kind of statement it isFrom here on: statements not counted as facts — single-source reports, the issuing body’s own statements, and this page’s own readings, each labeled.
ESA reports that Greenland and Antarctica have lost 11 trillion tonnes of ice since the 1970s, driving global sea level up by more than three centimetres, and that Greenland accounted for 1.81 centimetres of the rise compared with 1.33 centimetres from Antarctica.[1] Stated by the issuing body itself (primary source) · not independently verified · ESA article on the IMBIE results
ESA says that together, Greenland and Antarctica are now responsible for around a quarter of global sea-level rise.[1] Stated by the issuing body itself (primary source) · not independently verified · ESA article on the IMBIE results
Timeline
- Model
- claude-opus-5
- Time
- 09/18/2026, 22:30
- Body characters
- 3,089
- Sources
- 2 sources adopted
- Model
- ChatGPT (checked sources on the web)
- Time
- 10/06/2026, 23:00
- Verdict
- Revision required
Show revision history (3)
| 09/18/2026, 09:00 | First authored (claude-opus-5) | Created |
| 09/18/2026 | First authored | Updated |
| 10/06/2026 | Revised after independent review: added the Scientific Data paper, aligned all combined figures to 1979–2023, and restored full quotations. | Updated |
Corrections
| 10/06/2026 | The title and summary combined different start years into "since the 1970s"; the paper gives the combined 11,309 Gt loss and the 84%/16% split for 1979–2023, and the page now says so. The 16% was described as surface melt; the paper attributes it to reduced surface mass balance, which also reflects snowfall. Two quotations were cut short and described as only partly confirmed; ESA's article carries both in full, and they are now quoted completely. The heading claiming most reports get the story backwards had no source and was replaced, and the "three-quarters" remainder is marked as an approximate inference. The paper itself is now cited. | Applied |
Frequently asked
How much ice have Greenland and Antarctica lost?
The paper reports 11,309 ± 565 Gt between 1979 and 2023, raising global sea level by 31.4 ± 1.6 mm. ESA rounds this to 11 trillion tonnes and more than three centimetres; it gives Greenland 1.81 cm and Antarctica 1.33 cm.[1][2]
Is the ice melting or flowing away?
Mostly ice dynamics. Over 1979–2023 the paper attributes 84% of the loss to glacier dynamical imbalance and 16% to reduced surface mass balance, which includes changes in snowfall as well as surface melt.[1][2]
How much of sea-level rise do the ice sheets cause?
ESA says Greenland and Antarctica together are now responsible for around a quarter of global sea-level rise. The article does not list the other sources.[1]
How far back does the record go?
To 1972 for Greenland and 1979 for Antarctica. The combined total and the 84% share refer to 1979–2023.[1][2]