New map captures the Greenland Ice Sheet in unprecedented detail

Published 22-01-2026
News

A new high-resolution dataset provides the most detailed and up-to-date map of the Greenland Ice Sheet so far, showing the ice margin in late summer 2022. The dataset can be used to improve ice sheet and climate models, track changes in ice loss over time and support assessments of future sea-level rise.

Outline of the ice margin in 2022 (red line) shown in a small section of the new map. The green line shows the ice margin placement in the 1980's for comparison (Map: GEUS)

The Greenland Ice Sheet responds to a warming climate by losing mass. This mass loss is expressed through ice-margin retreat and ice thinning. To understand how the Greenland Ice Sheet responds to climate change, an accurate and up-to-date picture of its exact shape and size is needed. This ice-sheet outline can then serve as a baseline for models that predict the future evolution of the Greenland Ice Sheet.

That picture – called an ice mask – is now provided by a new dataset produced by researchers at GEUS and published in the journal Earth System Science Data. The dataset maps the Greenland Ice Sheet as it appeared in late summer 2022, offering a precise, time-specific snapshot of an ice sheet responding rapidly to a warming climate.

Mapped manually

The new ice mask – officially referred to as the PROMICE-2022 Ice Mask – is based on imagery from the European Union’s Copernicus Sentinel-2 satellite at 10-metres resolution. Rather than relying on automated classification, the research team manually delineated the entire ice margin around Greenland using these satellite images. This approach was particularly important in areas with complex terrain, debris-covered ice, seasonal snow and nunataks – rocky peaks protruding through the ice.

“Automated methods have improved a lot, but they still struggle in difficult areas,” says lead author Gregor Luetzenburg from GEUS. “Human judgement remains essential if you want a consistent and reliable outline.”

Therefore, producing the map is a substantial undertaking. This is why the map from 2022 now represents the most recent possible depiction of the actual extent of the ice – the work on the map has simply continued since the summer of 2022.   

Countless hours have been spent drawing the exact outline of the Greenland Ice Sheet manually (Photo: GEUS)

What the new map shows

According to the dataset, the Greenland Ice Sheet covered about 1.73 million square kilometres in 2022, about five times the size of Germany. The total length of the ice margin is approximately 53,000 kilometres, longer than Earth’s circumference, and more than 19,000 nunataks have been mapped within the ice-sheet interior. The ice mask also distinguishes between land-terminating ice and glaciers that terminate directly in the ocean – a key distinction for understanding ice dynamics and contributions to sea-level rise.

Future work should aim to systematically compare the newly derived ice mask with earlier products to show changes over time, Gregor Luetzenburg points out. However, earlier masks were generated using different data sources and methodologies, meaning that a direct comparison would largely capture methodological differences rather than genuine changes in ice-covered area.

“Developing approaches to level out these methodological differences is therefore an important next step and remains high on the research agenda,” he says.

Why does the ice margin matter?

An ice sheet outline like the one in the ice mask defines the boundary between ice-covered and ice-free terrain. These boundaries are fundamental inputs for climate and ice-sheet models, estimates of sea-level rise and studies of how meltwater flows from glaciers into the ocean.

Many widely used ice masks for Greenland are still based on satellite imagery from the 1990s or early 2000s. That is increasingly problematic, as the ice sheet has retreated substantially since then.

“When new measurements are combined with outdated ice margins, you risk introducing hidden biases into your analyses,” Luetzenburg explains. “This new dataset is designed to avoid exactly that.”

Open data – and updates to come

The PROMICE-2022 Ice Mask is openly available and distributed in several formats, making it suitable for both detailed satellite analyses and large-scale ice sheet and climate models. The researchers expect future updates as new satellite data become available.

“This is not a final product, but a new reference point. If we want to track how the Greenland Ice Sheet evolves in a warming climate, we need to keep our baseline data up to date,” says Luetzenburg.

Ice Sheet outline 2022

Below, you can download the map of the entire Greenland Ice Sheet margin as it was in late summer 2022.    

Scientific paper

Read the scientific publication 'PROMICE-2022 ice mask: a high-resolution outline of the Greenland Ice Sheet from August 2022' published in Earth System Science Data: 

https://doi.org/10.5194/essd-18-411-2026

Here, you'll also find access to all data. 

Gregor Luetzenburg
Postdoc
Glaciology and Climate
Phone+45 50101193
Johanne Uhrenholt Kusnitzoff
Editor
Press and Communication
Phone+45 91333954