Just 3% (specifically 3.2%) of the world’s glaciers, those ending in lakes, oceans, or ice shelves, account for more than half of global glacier ice loss.
A study led by researchers from the University of Birmingham and the University of Leeds, published in Nature Communications (23 October 2026), examined 216,502 glaciers worldwide (excluding the Greenland and Antarctic ice sheets). These water- terminating glaciers lost an estimated 134 billion tonnes of ice per year between 2000 and 2019.
Key findings
- These glaciers represent only about 3.2% of the total number but cover more than half of the world’s glacier area because they tend to be much larger than land- terminating ones.
- Breakdown of terminus types: ~96.8% end on land, 1.6% in lakes, 1.5% in the ocean, and 0.1% on ice shelves.
- Mass loss shares (2000–2019): land- terminating glaciers ~49.4%; lake-terminating ~24.0%; marine- terminating ~22.8%; shelf-terminating ~3.9%. The water- contact group therefore contributed slightly over half of total loss.
- After controlling for climate, size, and elevation, lake- terminating glaciers lost ice ~57% faster (relative to their size) than land– terminating ones. They also flow ~10% faster on average; ocean- terminating glaciers flow ~44% faster.
Why lake- ending glaciers lose ice faster
Possible mechanisms include calving (large ice chunks breaking off as icebergs) and melting of ice below the waterline by lake water. The exact relative contributions of the lakes themselves versus glacier size and shape remain under investigation. Lake- terminating glaciers occur in every major glacier region and, in most regions, lose ice faster than land- or ocean- ending ones.
Implications
Many models used to project glacier change, sea- level rise, water resources, and hazards do not fully account for lake- terminating glaciers.
The study provides a new global classification (freely available) to help improve those projections.
As the climate warms, more glaciers are shifting types: some ocean- ending glaciers in the Arctic are retreating onto land (potentially slowing loss), while growing proglacial lakes are turning land- ending glaciers into lake- ending ones (potentially accelerating loss).
Lead researcher Dr Joe Mallalieu (research done at Birmingham, now at Leeds) noted that lake- ending glaciers “really stand out” for rapid ice loss, and understanding the causes is especially important as glacier lakes become more common. Co-author Dr Nicholas Barrand (University of Birmingham) highlighted the value of combining expanded global datasets to compare glacier behaviour across settings.
Paper: Mallalieu et al. (2026), “Global-scale variability of glacier velocity and mass loss across terminus environments,” Nature Communications (DOI: 10.1038/s41467-026-78654-y).
The 57% faster loss rate refers specifically to lake- terminating glaciers compared with land- terminating glaciers.
What the number means
After researchers controlled for major confounding factors (climate, glacier size, and elevation), lake- ending glaciers still lost mass ~57% faster relative to their size than land- ending glaciers during 2000- 2019.
In other words:
- It is not simply that lake glaciers are bigger (though they often are).
- It is a higher specific mass- loss rate (ice lost per unit area or volume), once size and other variables are accounted for.
How the comparison was made
The team analysed 216,502 glaciers worldwide (excluding the Greenland and Antarctic ice sheets) and classified them by terminus type:
- Land- terminating
- Lake- terminating
- Ocean (marine)- terminating
- Ice- shelf- terminating
They then compared ice- flow speeds and mass-change rates across these categories.
Statistical controls removed the influence of climate, overall size, and elevation so the remaining difference could be more confidently linked to the terminus environment itself.
Why lake- ending glaciers lose ice faster
Two main physical processes are thought to drive the elevated rates:
- Calving: Large blocks of ice break off the glacier front into the lake as icebergs. This removes ice much more rapidly than surface melting alone.
- Subaqueous (underwater) melting: Relatively warmer lake water contacts the submerged ice front and melts it from below the waterline, undercutting the glacier and further promoting calving.
These processes are largely absent (or far weaker) for glaciers that end on dry land.
Supporting observations
- Lake- terminating glaciers flow ~10% faster on average than land- terminating ones (ocean- terminating glaciers flow ~44% faster).
- Lake- ending glaciers occur in every major glacier region and, in most regions, show higher specific mass- loss rates than both land- and ocean- ending glaciers.
Why this matters
As the climate warms, proglacial lakes are becoming more common.
Many currently land- terminating glaciers are expected to start ending in lakes, which could accelerate their mass loss beyond what models that ignore terminus type would predict.
Conversely, some marine- terminating glaciers that retreat onto land may slow down.
Accurately capturing the ~57% relative difference therefore improves projections of future sea- level rise, regional water resources, and glacier-related hazards.
Global-scale variability of glacier velocity and mass loss across terminus environments
The 57% figure refers to the specific (area- normalised) mass- loss rate of lake- terminating glaciers.
In the paper (Nature Communications, 2026), the authors state:
“specific (area- normalised) mass loss rates at lake- terminating glaciers are 57% greater than those at land- and marine-terminating glaciers.”
Precise meaning
After applying linear mixed- effects statistical models that controlled for climate (temperature and precipitation) plus a range of geometric and topographic factors (elevation, area, debris cover, polar deviation, etc.), lake-terminating glaciers still showed significantly greater specific mass loss than land- terminating glaciers.
The model- predicted difference was −0.162 m water equivalent per year (m w.e. a⁻¹). Relative to the land- terminating baseline, this equates to 57% greater losses.
Raw (uncontrolled) numbers for context
- Median specific mass- change rate (2000– 2019):
- Lake- terminating: −0.490 m w.e. a⁻¹
- Land- terminating: −0.245 m w.e. a⁻¹
- Marine- terminating: −0.239 m w.e. a⁻¹
So, the raw median for lake glaciers is roughly double that of land or marine glaciers. After statistical controls, the residual difference shrinks to the 57% figure, isolating the association with terminus type itself.
Why “specific” (area- normalised) matters
Total ice loss is dominated by the large size of many non- land glaciers.
The specific rate removes the size effect and shows how rapidly ice is being lost per unit area. The 57% value therefore indicates a higher intensity of loss at lake termini, not merely a size effect.
Note on the comparison
The abstract groups the comparison as “57% greater than those at land- and marine- terminating glaciers” because the land and marine medians are nearly identical.
In the detailed model results the primary contrast is with land- terminating glaciers (the statistical baseline). Marine- and shelf-terminating glaciers actually showed slightly lower specific losses than land-terminating ones after controls.
In short: once climate, size, elevation and other factors are accounted for, lake-ending glaciers still lose mass ~57% faster per unit area than land- ending ones.
Journal: Nature Communications, 17, Article number: 10873 (2026)
DOI: 10.1038/s41467-026-78654-y
Provided: University of Birmingham
Authors: Joseph Mallalieu,
Jonathan L. Carrivick,
Matthias Huss,
Iestyn D. Barr,
Nicholas E. Barrand &
Cassandra L. Raby
Abstract
The environment in which a glacier terminates can strongly influence its behaviour, stability and future evolution, yet the relationship between terminus type and glacier dynamics at the global scale remains poorly constrained. Here we present a globally-complete classification of glacier termini distinguishing between land, lake, marine and shelf environments, and integrate it with datasets of glacier geometry, dynamics and climate. We show that although lake-, marine- and shelf-terminating glaciers comprise only 3.2% of glaciers globally, they account for over half of global glacier area and mass loss. We also show that lake- and marine-terminating glaciers flow, on average, 10% and 44% faster than land-terminating glaciers, respectively. Furthermore, specific (area-normalised) mass loss rates at lake-terminating glaciers are 57% greater than those at land- and marine-terminating glaciers. Our findings underscore the need for improved representation of non-land glacier termini in models of glacier evolution and sea-level rise, and suggest that distinguishing the environmental and geometric controls of termini on glacier dynamics remains an important challenge for future research.
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