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Retreating glaciers created 2,500km of “new” coastline and 35 “new” islands in the Arctic between 2000 and 2020, according to a new study.
The research uses satellite images of more than 1,700 glaciers in Greenland, Alaska, the Canadian Arctic, Russian Arctic, Iceland and Svalbard.
The findings show that 85% of these glaciers retreated over 2000-20, revealing 123km of new coastline per year on average.
The study, published in Nature Climate Change, links the acceleration in glacier melt to warmer ocean and air temperatures.
The authors find that just 101 glaciers – less than 6% of the total – were responsible for more than half of the total additional coastline length.
For example, the retreat of the Zachariae Isstrom glacier in north-east Greenland revealed 81km of new coastline alone.
The study warns that the freshly revealed coastlines are more prone to landslides, which may, in turn, create “dangerous tsunamis” that pose risks to human life and infrastructure.
A scientist not involved in the study tells Carbon Brief that it remains “unclear” what the implications of the new coastlines will be for the people and ecosystems of the Arctic.
He suggests that they “may become home to important ecosystems that play a hitherto unquantified role in the global carbon cycle”.
Glacier melt
Glaciers are slow-moving rivers of ice found on almost every continent in the world. They typically advance downhill by a few centimetres every day, driven by their own weight.
The head of a glacier is always found on land – typically at high altitude, where temperatures are low. Here, precipitation and avalanches cause snow to build up on the surface of the glacier. Over time, the snow compacts into ice, adding mass to the glacier.
Meanwhile, the tail end of the glacier is typically found at lower elevations where the air is warmer. Here, melting ice and evaporating water cause glaciers to lose mass.
As the planet warms, glaciers are melting more rapidly. This often causes the bottom of the glacier – known as the “terminus“, “snout” or “toe” – to recede, reducing the overall length of the glacier. This is known as terminus retreat.
Over 2000-19, glaciers collectively lost around 267bn tonnes (gigatonnes, or Gt) of ice every year. A recent report by the UN warned that many glaciers will “inevitably” disappear entirely over the coming decades.
A separate study estimated that even if the world successfully limits global warming to 1.5C, glaciers could lose a quarter of their total mass by 2100.
Glaciers can be broadly split into categories based on their location. For example, while “land-terminating” glaciers end on land, “marine-terminating” glaciers flow into the ocean, where they often end in a “floating glacier tongue” that sits on the surface of the water.
When marine-terminating glaciers melt and retreat, new areas of coastline are often revealed. Research shows that marine-terminating glaciers in the northern hemisphere have cumulatively lost 10Gt of mass every year over 2000-20 due to terminus retreat.
The northern hemisphere is home to around 1,500 of the world’s roughly 200,000 glaciers.
The new study assesses how much new coastline has been exposed due to terminus retreat in marine-terminating glaciers in the northern hemisphere over 2000-20.
Satellite monitoring
The authors used a pre-existing dataset to identify all the marine-terminating glaciers in the northern hemisphere. They then manually assessed satellite imagery – mainly from Sentinel-2 – to digitise the new coastline that was exposed as a result of glacier retreat around Greenland, Alaska, the Canadian Arctic, Russian Arctic, Iceland and Svalbard over 2000-20.
Dr Jan Kavan is the lead author of the study and a researcher at the University of South Bohemia’s Centre for Polar Ecology. He tells Carbon Brief that the researchers opted for a manual approach because algorithms trained to identify the position of glaciers “don’t work very well” on coastlines.
This is because Arctic coastlines tend to be highly variable, Kavan explains. For example, glaciers near the coastline may be covered in debris – making it hard for an algorithm to recognise them.
Dr Simon Cook is a senior lecturer in environmental sciences at the University of Dundee, who wrote a “news and views” piece about the study published in Nature climate change. He praises the study, telling Carbon Brief that manually identifying coastlines is “labour-intensive and slow work, but widely regarded to be robust”.
The authors inspected 1,704 marine-terminating glaciers in total. They find that 2,466km of new coastline formed between 2000 and 2020 – an average of 123km of new coastline every year.
The map below shows where the coastline was added (red) and lost (blue) due to changes in glacier terminus positions over 2000-20. The yellow circles the total length of new coastline added in different regions, where larger circles indicate greater additions.
The authors note that the rate of new coastline formation varies highly between regions. Just 101 glaciers were responsible for more than half of the total additional coastline length, they say.
Two-thirds of the new coastline identified in this study were in Greenland, the authors say. The melt of the Zachariae Isstrom glacier in north-east Greenland has resulted in the formation of 81km of new coastline – more than twice as much as any other glacier in the study – according to the paper.
Retreating glaciers also exposed 35 new islands with areas larger than 0.5 square kilometres (km2), according to the study.
Changing coastlines
Rising ocean and air temperatures are the main reason that marine-terminating glaciers are rapidly losing mass, the study says. However, many other factors may affect how quickly new coastline forms due to glacier melt.
According to the authors, 85% of the glaciers in the study retreated between 2000 and 2020.
However, not all of these led to the development of new stretches of coastline.
For example, glaciers that stretch out far into the sea could experience “extensive retreat” without any new coastline forming, according to the paper.
Conversely, glaciers in “deep and narrow fjords” can expose long new areas of coast by losing only a small volume of ice.
The authors note that the most “dramatic” glacier retreats are due to ice shelves or floating tongues breaking off the main glacier and collapsing into the water.
Meanwhile, glacier advances – when glaciers gain mass more quickly then they lose it, or temporarily “surge” forwards – can cause a loss of coastline. (Surges are short-lived periods when the glacier moves faster than its normal rate, often due to meltwater which builds at the base of the glacier and acts as a lubricant.)
The paper finds that more than 50 metres of coastline was lost due to glacier advances. Two-thirds of this gain was in Svalbard due to a “surge” of the Nathorstbreen glacier system, according to the paper.
Lead author Kavan tells Carbon Brief that other studies have assessed coastline gain from “individual glaciers” or “small regions”, but says this is the first paper to quantify coastline gain across the entire northern hemisphere for a uniform time period.
Dr Robert McNabb, a lecturer at Ulster University who was not involved in the study, tells Carbon Brief the study “highlights the importance and immense value of having long-term, freely available satellite archives for research”.
Tsunami risk
Glacier melt is often discussed in the context of water security, as the world’s 200,000 glaciers store around 70% of the Earth’s fresh water. However, Kavan tells Carbon Brief that the impact of retreating glaciers on the bedrock is often “neglected”.
Using a map of rock types across the Arctic, the authors analyse the changing conditions of the new coastlines. They find that most of the new coastline is formed of metamorphic bedrock – a type of rock formed from intense heat and pressure. Meanwhile, softer sedimentary rocks, which are more susceptible to erosion, dominate the newly formed coastlines in eastern Svalbard.
In his news and views piece, Cook – the University of Dundee environmental sciences lecturer – explains that the newly revealed coastlines are known as “paraglacial”. He writes:
“Paraglacial coasts differ from other established areas of Arctic coastline because permafrost will not yet have had time to develop in these freshly revealed areas, meaning that they are more easily eroded by wave action, mass wasting and other processes because of a lack of icy cement. They are, therefore, expected to be highly dynamic.”
Cook says it is “currently unclear” what the implications of the new paraglacial coastlines will be for the people and ecosystems of the Arctic. He suggests that the new coastlines “may become home to important ecosystems that play a hitherto unquantified role in the global carbon cycle”.
Freshly revealed paraglacial coastlines can be more prone to landslides, which may, in turn, cause “dangerous tsunamis”, the paper notes. As an example, it points to a tsunami on 17 June 2017 in Greenland, which caused “substantial infrastructure damage and loss of life”.
Dr Anna Irrgang is a coastal geomorphologist at the Alfred Wegner Institute and was not involved in the study. She tells Carbon Brief that the study “may help in detecting potential risk-zones” for such tsunamis.
She adds that the dataset provided in this study can be used as a “first estimation of the hazard potential”, but adds that “a more in-depth risk analysis needs to be undertaken at the local scale, where communities might be exposed to these arising dangers”.
Meanwhile, Kavan tells Carbon Brief that marine-terminating glaciers are considered “biodiversity hotspots”. Meltwater from the glacier causes upwellings at the terminus of the glacier, creating “nutrient-rich water” that is vital for many polar species, he says.
As a result, ongoing glacier retreat may result in many of these habitats being lost, putting species like bearded seals and Arctic-dwelling birds at risk, he adds.
The post Global warming is ‘exposing’ new coastlines and islands as Arctic glaciers shrink appeared first on Carbon Brief.
Global warming is ‘exposing’ new coastlines and islands as Arctic glaciers shrink
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An older teaching about land acknowledgement
As I have come to understand the spirit and intention of land acknowledgement, I often return to fond memories of my grandmother and her words of wisdom. She taught that the health of the places we call home comes first, because the wellbeing of the people depends on it.
In her teaching, land acknowledgement began with the land. Long before it became a paragraph read at the start of a meeting, it was a way of recognizing a homeland: its waters, its species, its seasons, and the spirit that revealed whether the place was well.
Her teaching echoes a practice found across many Indigenous Nations. Haudenosaunee gatherings, for example, have long opened with the Ohén:ton Karihwatéhkwen, the Thanksgiving Address, often translated as “the words that come before all else.” The speaker greets and gives thanks to the people, the earth, the waters, the plants, the animals, the winds, the sun, the moon and the stars. Only after everything that sustains life has been acknowledged does the gathering turn to its own business.
That order changes what an acknowledgement is for. Its purpose was to share the story of a place with neighbours and to draw them into the work of tending it. People entered the story second, as the ones responsible for what had just been named.
Understood this way, an acknowledgement does more than open a meeting. It asks us to reconsider where we stand, and what we owe the ground beneath us.
Nations among nations
In her teaching, people are one nation among many. The salmon are a nation. So are the cedars, the bison, the medicine plants, and the pollinators. Each belongs to a place, carries its own responsibilities, and offers gifts no other nation can give.
This idea of kinship runs through many Indigenous philosophies. The phrase “all my relations,” heard in ceremonies and gatherings across Turtle Island, is a reminder that family extends beyond people to the animals, plants, waters and lands that make life possible. Some Indigenous languages carry the same understanding in their grammar, speaking of many plants, animals and natural forces as living beings rather than objects.
Sovereignty, understood through this relationship, is a kind of standing more than a form of control. Each nation belongs fully to its place and carries its share of that place’s life. No nation thrives alone, and none thrives by taking over the whole.
The land is also the source of instruction. Over generations, people watched how a river valley or a stretch of prairie kept itself well: who arrived when, who fed whom, and how much could be taken before the giving stopped. In my grandmother’s telling, those observations became instructions, and those instructions helped shape law and protocol. They guided when to harvest, where to camp, how to enter a neighbour’s territory, and what was owed in return.
Indigenous legal scholars today often describe this as law that comes from the land itself, learned by watching how living systems sustain one another. A plainer name for it is knowing how to live somewhere.
The host and the guest
One of the clearest teachings in this understanding of the world is the relationship between host and guest. My grandmother invited us to recognize that relationship in the lives of plants and animals.
A host prepares the place before anyone arrives. A beaver family dams a stream, and the pond becomes a home for fish, frogs, birds and plants. A fallen tree becomes a nurse log, feeding the next generation of seedlings as it returns to the soil.
A host offers first. A flowering plant sets out nectar. A berry bush ripens fruit. These provisions come in their own season, not whenever a visitor happens to want them.
A host also makes its presence known. Birdsong, scent and the marks left along a trail tell newcomers that a place is already inhabited. The visitor does not arrive in an empty world.
The guest has responsibilities too. A guest attends to the season and to what the place can offer. A guest does not assume that everything within reach is theirs to take. A guest leaves something that helps sustain the relationship.
A bee takes nectar and carries pollen. Read through this teaching, that exchange offers an image of visiting well: receiving a gift while helping the host continue its life.
Many Indigenous harvesting protocols carry the same ethic into daily practice: ask before taking, take only what is needed, offer thanks, and leave enough for others and for the plant or animal to recover.
None of this suggests that every relationship in nature is peaceful or generous. These are ways of seeing responsibilities that people can learn to carry.
Everyone is both
No being is only a host or only a guest.
A tree makes room for other life while depending on soil, water, sunlight, fungi, and relationships beyond itself. People, too, may welcome others into their homes while remaining dependent on the larger homeland that sustains them.
The distinction between host and guest is therefore about roles, not ranks. Everyone receives. Everyone has something to give.
The question is whether the exchange sustains the place.
A visitor who takes without restraint leaves less for those who come next. A host who neglects the place has less to offer. Both have responsibilities, and neither can fulfil them alone.
This is the heart of reciprocity, a principle found across Indigenous philosophies: relationships stay healthy when gifts move in both directions. The Haudenosaunee teaching of the seventh generation extends that exchange across time, asking that decisions made today leave the place well for those not yet born.
Mutual benefit begins here, with the recognition that different beings carry different gifts and obligations.
What people carry forward
My grandmother’s teaching connects these relationships to the ways people meet their neighbours.
The host prepares a place, offers food and rest, and explains where the visitor has arrived. The guest makes themselves known, explains why they have come, listens to the terms of the visit, and brings something in return. The gift may be material. It may also be labour, knowledge, news, or a commitment to help.
Nations around the Great Lakes carried this ethic into treaty. The Dish with One Spoon, an agreement among the Haudenosaunee, Anishinaabe and allied Nations, describes shared hunting grounds as a single dish. Everyone eats from it with one spoon, takes only what they need, leaves enough for others, and keeps the dish clean. The Two Row Wampum, between the Haudenosaunee and European newcomers, shows two vessels travelling side by side on the same river, each keeping its own ways and neither steering the other.
In this understanding, acknowledgement is more than naming the people associated with a territory. It is learning enough about a homeland to behave responsibly within it.
Whose home is this? What sustains it? What laws and agreements guide our presence? What can we receive, and what must we return?
These questions make acknowledgement a relationship rather than a recital.
They also make it diplomatic. A guest who recognizes the host’s homeland recognizes that they have entered a place with its own relationships and responsibilities. A host who welcomes the guest makes room for an encounter governed by those relationships.
Neither arrives without standing. Neither arrives without obligations.
Beginning with place
I write from the shores of the Bay of Quinte. Here, the teaching asks me to begin with the water, the shoreline, and the life they sustain. Before I describe myself, I must attend to where I am.
That does not make people or history less important. It places them within the homeland that gives them meaning. The people, their laws, their agreements, and their responsibilities all belong to the place.
In a time of longer fire seasons, troubled waters, and uncertainty about what the next season will bring, this teaching asks something difficult and useful of us: pay attention before you speak.
An acknowledgement cannot tell the story of a place if the speaker has stopped noticing it.
The land came first. Beginning there again means learning to name what sustains us, and accepting that what sustains us also asks something of us.
By Rye Karonhiowanen Barberstock
Photo by Andrik Langfield on Unsplash
The post The Land Came First appeared first on Indigenous Climate Hub.
Carbon dioxide (CO2) emissions from fossil fuels and cement are projected to fall by around 0.4% in 2026 to 38.2bn tonnes of CO2 (GtCO2), according to new figures from the Global Carbon Project.
This guest post is by:
- Dr Zeke Hausfather, Carbon Brief’s climate science contributor
- Prof Pierre Friedlingstein, chair of mathematical modelling of climate systems at the University of Exeter and part of the Global Carbon Project team.
Carbon dioxide (CO2) emissions from fossil fuels and cement are projected to fall by around 0.4% in 2026 to 38.2bn tonnes of CO2 (GtCO2), according to new figures from the Global Carbon Project.
The 21st edition of the annual “global carbon budget” report, published today, says that this small decline is largely due to a 1.9% drop in emissions from oil and the energy shock triggered by the Iran conflict and the closure of the strait of Hormuz.
Emissions from coal continue to increase slightly.
The Global Carbon Project’s projections for fossil fuel and cement CO2 emissions in 2026 are preliminary, with a range that spans a fall of -1.5% to a rise of +0.6%.
This means a small increase in emissions can not be ruled out.
Emissions from land-use change, such as deforestation, are projected to rise in 2026.
This is primarily driven by peat fires and forest degradation in south-east Asia and is linked to the development of a strong El Niño event this year.
As a result, total CO2 emissions from fossil fuels and land use are projected to reach a record high of 43.3GtCO2 in 2026 – marginally above 42.8GtCO2 in 2025.
Research published alongside the report by the same team in Nature Climate Change finds that the growth in solar, wind and electric vehicles (EVs) now offsets around two-thirds of the emissions that would otherwise come from rising energy demand.
However, the d