Satellites show Earth lost more than 12 trillion tons of ice from Greenland and Antarctica over ~47 years (roughly 1979- 2023), according to a major study published in Scientific Data.

Key findings from the international collaboration (led in part by the European Space Agency’s IMBIE initiative, incorporating NASA satellite data for a longer record):

Total ice loss: about 12.5 trillion tons (11.3 trillion metric tons). This is enough to cover the continental United States with ice roughly 5 feet (1.5 meters) deep.

Sea- level contribution: This melt alone raised global sea levels by about 1 inch (≈3.1 cm) since 1979 (on top of other factors). Greenland accounts for a somewhat larger share.

Main driver: ~5/6 (about 84%) of the loss comes from dynamic processes, warmer ocean water undercutting and melting ice sheets from below/sides, accelerating glacier flow into the ocean, rather than surface melting from warmer air.

Acceleration: Ice sheets were relatively stable in the 1970s-1990s; losses ramped up later, especially in the 2010s. A temporary slowdown around 2020- 2023 (partly due to heavy snowfall in East Antarctica offsetting West Antarctic losses) was viewed as short- term variability; the longer- term accelerating trend has resumed.

Methods: Combined data from dozens of independent surveys and 27 satellites (including earlier Landsat archives) for the longest continuous satellite- based mass- balance record of the two ice sheets.

Scientists involved (including Ines Otosaka of Northumbria University and Eric Rignot of UC Irvine) emphasize that the dynamical ice discharge raises concerns about potential tipping points or instability, particularly in parts of Antarctica, with implications for continued sea- level rise and coastal flooding risk even if warming stabilizes. Independent experts noted the multi- method approach increases confidence in the upward trend.

The article is an Associated Press report by Seth Borenstein (dated around mid- to- late September 2026 in various outlets).

This extends earlier satellite records (previously focused more on the 1990s onward) and aligns with the broader observed pattern of accelerating polar ice loss linked to climate change.

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SMB models refer to Surface Mass Balance models (or, more precisely, the surface mass balance components derived from regional climate models).

In the context of the Greenland and Antarctic ice- sheet mass- balance study we discussed:

What is Surface Mass Balance (SMB)?

SMB is the net gain or loss of mass at the surface of an ice sheet. It is calculated as:

$$\text{SMB} = \text{snowfall accumulation} – (\text{meltwater runoff} + \text{sublimation} + \text{evaporation} + \text{blowing-snow erosion})$$

Positive SMB means the ice sheet is gaining mass at the surface (mainly from snowfall). Negative SMB means net surface loss (mainly from melting and runoff).

Role of SMB models in the study

The paper uses regional climate models (RCMs) to estimate SMB. These models simulate the atmosphere– ice- sheet interactions at relatively high spatial resolution over the polar regions. Common examples used in ice- sheet research include:

• MAR (Modèle Atmosphérique Régional)
• RACMO (Regional Atmospheric Climate Model)
• HIRHAM
• Other similar atmospheric models forced by global reanalyses (e.g., ERA5) or climate models

These models provide the time- varying SMB fields that are combined with satellite observations in the input- output method (also called the mass- budget method):

• Ice discharge (how much ice flows into the ocean) is measured from satellites (velocity + ice thickness).
• SMB is taken from the regional climate models.
• Mass balance = SMB − ice discharge (plus any basal melt terms where relevant).

Key finding from the paper related to SMB

Of the total 11,309 ± 565 Gt of ice lost from Greenland and Antarctica (1979- 2023):

• 84% came from ice dynamical imbalance (accelerated glacier flow and discharge into the ocean, largely driven by warmer ocean water).
• 16% came from reduced SMB (mainly increased surface melting and runoff, especially in Greenland).

In Greenland, the split was roughly 67% dynamics / 33% SMB. In Antarctica, nearly all the loss was dynamical; SMB changes were smaller or even positive in some periods due to increased snowfall.

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Mass balance of the Greenland and Antarctic ice sheets from the 1970s to 2023

The Greenland and Antarctic ice sheets are major contributors to global mean sea- level rise and the largest source of uncertainty in future projections. This data descriptor compares and combines 42 independent estimates of ice- sheet mass balance derived from satellite observations of changes in ice flow, volume, and gravitational attraction.

It covers:

• Greenland Ice Sheet (GrIS): 1972- 2023
• Antarctic Ice Sheet (AIS) and its sectors (West Antarctica/WAIS, East Antarctica/EAIS, Antarctic Peninsula/APIS): 1979- 2023

Regional climate models are used to partition total mass balance into surface mass balance (SMB) and ice dynamical imbalance.

Key result: The ice sheets lost 11,309 ± 565 billion tonnes (Gt) of ice between 1979 and 2023. Glacier dynamical imbalance drove 84% of the loss; reduced surface mass balance accounted for the remaining 16%. The dataset supports tracking ice-sheet contributions to sea- level rise and constraining future projections.

Main quantitative findings

• Combined (1979- 2023): 11,309 ± 565 Gt lost → 31.4 ± 1.6 mm global sea- level rise.
• Antarctica (1979- 2023): 4,780 ± 513 Gt lost → 13.3 ± 1.4 mm sea- level rise. Essentially all of Antarctica’s losses were driven by ice dynamics.
• Greenland (1972- 2023): 6,215 ± 467 Gt lost (average rate 119 ± 9 Gt yr⁻¹). ~67% from increased ice discharge, ~33% from reduced SMB. Greenland was near balance in the 1970s; losses rose from ~60 Gt yr⁻¹ in the 1980s to much higher rates later (e.g., hundreds of Gt yr⁻¹ in the 2010s). nature.com

Losses accelerated from the 1990s onward. A temporary slowdown in overall loss rates around 2020- 2023 (linked to high snowfall in East Antarctica and milder Greenland summers) is described as short- term variability rather than a change in the long- term trend.

Methods overview

Techniques: Input- output method (ice discharge and SMB models), satellite altimetry (volume change), and satellite gravimetry (mass change from gravity).

Satellites: Data from 27 missions, including early Landsat archives for velocity back to the 1970s.

Standardization: Individual estimates converted to monthly rates of mass change; reconciled into consensus time series with uncertainties. Peripheral glaciers/ice caps are accounted for where relevant.

Only mass changes that contribute to sea level are included (ice- shelf thinning/retreat and grounded ice below sea level are excluded from the sea-level contribution figures).

Data availability

Reconciled mass- balance time series (rates and cumulative anomalies for total mass, SMB, and dynamics, with uncertainties) are freely available at:

https://doi.org/10.5285/128c5e33-5224-4197-82f0-19dcc95b80a0

Code for aggregation is also openly available.

This extends previous IMBIE assessments (which focused more on the post- 1992 period) and provides the longest continuous satellite- based consensus record of the two ice sheets. The paper is open access.

Published:  Scientific Data volume 13, Article number: 1301 (2026)

DOI: 10.1038/s41597-026-08088-0

Authors: Lead authors include Inès N. Otosaka, Andrew Shepherd, and a large international team (IMBIE – Ice Sheet Mass Balance Inter-comparison Exercise).

Abstract

The Greenland and Antarctic ice sheets are major drivers of global mean sea level rise and are predicted to continue to do so in the future. However, they also represent the largest source of uncertainty in projections of future sea level rise making robust estimates of observed ice sheet mass changes critical. Here, we compare and combine 42 independent estimates of ice sheet mass balance derived from satellite observations of temporal changes in ice sheet flow, volume, and gravitational attraction to determine the ice sheet mass balance from 1972 (Greenland) and 1979 (Antarctica) until 2023. We then use regional climate models to partition the total mass balance into contributions associated with surface mass balance and ice dynamical imbalance. The ice sheets lost 11,309 ± 565 billion tonnes of ice between 1979 and 2023, with glacier dynamical imbalance driving 84% of the ice loss and surface mass balance the remainder. This dataset can be used to track the contribution of the ice sheets to sea level rise and constrain projections of future sea level rise.