The recent rapid retreat of an Antarctic glacier could be unprecedented, a new study suggests, a finding which could have major implications for future sea-level rise.

The researchers found that Hektoria Glacier retreated by more than 8km (5 miles) in just two months in late 2022.

The authors believe it could be the first modern example of a process where the front of a glacier resting on the seabed rapidly destabilises.

But other scientists argue that this part of the glacier was actually floating in the ocean – so while the changes are impressive, they are not so unusual.

Floating tongues of glaciers extending into the sea – called ice shelves – are much more prone to breaking up than glacier fronts resting on the seabed.

That’s because they can be more easily eaten away by warm water underneath.

Solving the ‘whodunnit’

That Hektoria has undergone huge change is not contested. Its front retreated by about 25km (16 miles) between January 2022 and March 2023, satellite data shows.

But unravelling the causes is like a “whodunnit” mystery, according to study lead author Naomi Ochwat, research affiliate at the University of Colorado Boulder and post-doctoral researcher at the University of Innsbruck.

The case began way back in 2002 with the extraordinary collapse of an ice shelf called Larsen B in the eastern Antarctic Peninsula. About 3250 sq km (1250 sq miles) of ice shelf was lost, roughly the size of Cambridgeshire or Gloucestershire.

Larsen B had been effectively holding Hektoria Glacier back. Without it, Hektoria’s movement sped up and the glacier thinned.

But the bay vacated by the ice shelf was eventually filled with sea-ice “fastened” to the seabed, helping to partly stabilise Hektoria.

That was until early 2022, when the sea-ice broke up.

What followed was further loss of floating ice from the front of Hektoria, as large, flat-topped icebergs broke off or “calved”, and the ice behind sped up and thinned.

That is not unusual. Iceberg calving is a natural part of ice sheet behaviour, even though human-caused climate change makes the loss of ice shelves much more likely.

What was unprecedented, the authors argue, was what happened in late 2022, when they suggest the front of the glacier was “grounded” – resting on the seabed – rather than floating.

In just two months, Hektoria retreated by 8.2km. That would be nearly ten times faster than any grounded glacier recorded before, according to the study, published in Nature Geoscience.

This extraordinary change, the authors say, could be thanks to an ice plain – a relatively flat area of bedrock on which the glacier lightly rests.

Upward forces from the ocean water could “lift” the thinning ice essentially all at once, they argue – causing icebergs to break off and the glacier to retreat in quick time.

“Glaciers don’t usually retreat this fast,” said co-author Adrian Luckman, professor of geography at Swansea University.

“The circumstances may be a little particular, but this rapid retreat shows us what may happen elsewhere in Antarctica where glaciers are lightly grounded, and sea-ice loses its grip,” he added.

What makes this idea even more tantalising is that this process has never been observed in the modern world, the authors say. But markings on the seafloor suggest it may have triggered rapid ice loss into the ocean in the Earth’s past.

“What we see at Hektoria is a small glacier, but if something like that were to happen in other areas of Antarctica, it could play a much larger role in the rate of sea-level rise,” said Dr Ochwat.

That could include Thwaites – the so-called “doomsday” glacier because it holds enough ice to raise global sea-levels by 65cm (26in) if it melted entirely.

“It’s really important to understand whether or not there are other ice plain areas that would be susceptible to this kind of retreat and calving,” Dr Ochwat added.

Other scientists unconvinced

But other researchers have contested the study’s findings.

The controversy surrounds the position of the “grounding line” or “grounding zone” – where the glacier loses contact with the seabed and starts to float in the ocean.

“This new study offers a tantalising glimpse into what could be the fastest rate of retreat ever observed in modern-day Antarctica,” said Dr Frazer Christie, glaciologist and senior Earth observation specialist at Airbus Defence and Space.

“But there is significant disagreement within the glaciological community about the precise location of Hektoria Glacier’s grounding line because it’s so difficult to get accurate records from radar satellites in this fast-flowing region,” he added.

The location of the grounding line may sound trivial, but it is crucial to determine whether the change was truly unprecedented.

“If this section of the ice sheet was in fact floating [rather than resting on the seabed], the punchline would instead be that icebergs calved from an ice shelf, which is much less unusual behaviour,” said Dr Christine Batchelor, senior lecturer in physical geography at Newcastle University.

“I think the mechanism and rate of retreat proposed are plausible in Antarctic ice plain settings, but because of uncertainty about where the grounding zone was located at Hektoria, I am not fully convinced that this has been observed here,” she added.

But where there is little debate is that the fragile white continent – once thought largely immune from the impacts of global warming – is now changing before our eyes.

“While we disagree about the process driving this change at Hektoria, we are in absolute agreement that the changes in the polar regions are scarily rapid, quicker than we expected even a decade ago,” said Anna Hogg, professor of Earth observation at the University of Leeds.

“We must collect more data from satellites, so that we can better monitor and understand why these changes are occurring and what their implications are [for sea-level rise].”

Additional reporting by the Visual Journalism team

Cachella Smith and Will Grant, Reporting from Kingston

• Published1 November 2025, 15:47 GMT

Updated 9 minutes ago

A flight carrying British aid arrived in Jamaica early on Saturday to help with recovery efforts after Hurricane Melissa, as the UK plans its first chartered flight to bring British nationals home later on Saturday.

The aid flight brought more than 3,000 emergency shelter kits as part of a £7.5m regional emergency package.

Part of the funding will be used to match public donations up to £1m to the International Red Cross and Red Crescent – with King Charles and Queen Camilla among those who have donated.

Despite aid arriving in Jamaica in recent days, fallen trees and landslides have complicated distribution after Hurricane Melissa devastated parts of the island, killing at least 19 people.

The hurricane made landfall in Jamaica on Tuesday as a category five storm and was one of the most powerful hurricanes ever measured in the Caribbean.

Melissa swept across the region over a number of days and left behind a trail of destruction and dozens of people dead. In Haiti, at least 30 people were killed, while Cuba also saw flooding and landslides.

Jamaica’s Information Minister Dana Morris Dixon said on Friday “there are entire communities that seem to be marooned and areas that seem to be flattened”.

The UK initially set aside a £2.5 million immediate financial support package, with an additional £5 million announced by Foreign Secretary Yvette Cooper on Friday.

Cooper said the announcement came as “more information is now coming through on the scale of devastation caused by Hurricane Melissa, with homes damaged, roads blocks and lives lost”.

The British Red Cross said the King and Queen’s donation would help the International Federation of Red Cross and Red Crescent (IFRC) “continue its lifesaving work” – which includes search and rescue efforts in Jamaica as well as ensuring access to healthcare, safe shelter and clean water.

The Red Cross said, as of Saturday morning, that 72% of people across Jamaica still do not have electricity and around 6,000 are in emergency shelters.

Until the Jamaican government can get the broken electricity grid back up and running, any generators aid agencies can distribute will be vital.

So too will tarpaulins, given the extent of the housing crisis.

Meanwhile, with so many in need of clean drinking water and basic food, patience is wearing thin and there are more reports of desperate people entering supermarkets to gather and give out whatever food they can find.

The BBC has seen queues for petrol pumps, with people waiting for hours to then be told there is no fuel left when they reach the front of the queue.

Some people are seeking fuel for generators, others for a car to reach an area in which they can contact people, with the power down across most of the island.

The country’s health minister, Dr Christopher Tufton, on Saturday described “significant damage” across a number of hospitals – with the Black River Hospital in St Elizabeth being the most severely affected.

“That facility will have to be for now totally relocated in terms of services,” he said.

“The immediate challenge of the impacted hospitals is to preserve accident and emergency services,” Dr Tufton added. “What we’re seeing is that a lot of people are coming in now to these facilities with trauma-related [injuries] from falls from the roof, to ladders, to nails penetrating their feet”.

The minister said arrangements had been made for the ongoing supply of fuel to the facilities as well as a “daily supply of water”.

Although aid is entering the country, landslides, downed power lines and fallen trees have made certain roads impassable.

However, some of the worst affected areas of Jamaica should finally receive some relief in the coming hours.

At least one aid organisation, Global Empowerment Mission, rolled out this morning from Kingston with a seven-truck convoy to Black River, the badly damaged town of western Jamaica, carrying packs of humanitarian assistance put together by volunteers from the Jamaican diaspora community in Florida.

Help is also coming in from other aid groups and foreign governments via helicopter.

It remains only a small part of what the affected communities need but authorities insist more is coming soon.

Around 8,000 British nationals were thought to have been on the island when the hurricane hit.

The UK’s first chartered flight to bring British citizens home is set to leave Kingston’s Norman Manley International Airport late on Saturday.

The UK foreign office has asked travellers to register their presence on the island.

The department also advises travellers to contact their airline to check whether commercial options are available.

A new four-lane highway cutting through tens of thousands of acres of protected Amazon rainforest is being built for the COP30 climate summit in the Brazilian city of Belém.

It aims to ease traffic to the city, which will host more than 50,000 people – including world leaders – at the conference in November.

The state government touts the highway’s “sustainable” credentials, but some locals and conservationists are outraged at the environmental impact.

The Amazon plays a vital role in absorbing carbon for the world and providing biodiversity, and many say this deforestation contradicts the very purpose of a climate summit.

Along the partially built road, lush rainforest towers on either side – a reminder of what was once there. Logs are piled high in the cleared land which stretches more than 13km (8 miles) through the rainforest into Belém.

Diggers and machines carve through the forest floor, paving over wetland to surface the road which will cut through a protected area.

Claudio Verequete lives about 200m from where the road will be. He used to make an income from harvesting açaí berries from trees that once occupied the space.

“Everything was destroyed,” he says, gesturing at the clearing.

“Our harvest has already been cut down. We no longer have that income to support our family.”

He says he has received no compensation from the state government and is currently relying on savings.

He worries the construction of this road will lead to more deforestation in the future, now that the area is more accessible for businesses.

“Our fear is that one day someone will come here and say: ‘Here’s some money. We need this area to build a gas station, or to build a warehouse.’ And then we’ll have to leave.

“We were born and raised here in the community. Where are we going to go?”

His community won’t be connected to the road, given its walls on either side.

“For us who live on the side of the highway, there will be no benefits. There will be benefits for the trucks that will pass through. If someone gets sick, and needs to go to the centre of Belém, we won’t be able to use it.”

The road leaves two disconnected areas of protected forest. Scientists are concerned it will fragment the ecosystem and disrupt the movement of wildlife.

Prof Silvia Sardinha is a wildlife vet and researcher at a university animal hospital that overlooks the site of the new highway.

She and her team rehabilitate wild animals with injuries, predominantly caused by humans or vehicles.

Once healed, they release them back into the wild – something she says will be harder if there is a highway on their doorstep.

“From the moment of deforestation, there is a loss.

“We are going to lose an area to release these animals back into the wild, the natural environment of these species,” she said.

“Land animals will no longer be able to cross to the other side too, reducing the areas where they can live and breed.”

The Brazilian president and environment minister say this will be a historic summit because it is “a COP in the Amazon, not a COP about the Amazon”.

The president says the meeting will provide an opportunity to focus on the needs of the Amazon, show the forest to the world, and present what the federal government has done to protect it.

But Prof Sardinha says that while these conversations will happen “at a very high level, among business people and government officials”, those living in the Amazon are “not being heard”.

The state government of Pará had touted the idea of this highway, known as Avenida Liberdade, as early as 2012, but it had repeatedly been shelved because of environmental concerns.

Now a host of infrastructure projects have been resurrected or approved to prepare the city for the COP summit.

Adler Silveira, the state government’s infrastructure secretary, listed this highway as one of 30 projects happening in the city to “prepare” and “modernise” it, so “we can have a legacy for the population and, more importantly, serve people for COP30 in the best possible way”.

Speaking to the BBC, he said it was a “sustainable highway” and an “important mobility intervention”.

He added it would have wildlife crossings for animals to pass over, bike lanes and solar lighting. New hotels are also being built and the port is being redeveloped so cruise ships can dock there to accommodate excess visitors.

Brazil’s federal government is investing more than $81m (£62m) to expand the airport capacity from “seven to 14 million passengers”. A new 500,000 sq-m city park, Parque da Cidade, is under construction. It will include green spaces, restaurants, a sports complex and other facilities for the public to use afterwards.

Some business owners in the city’s vast open-air Ver-o-peso market agree that this development will bring opportunities for the city.

“The city as a whole is being improved, it is being repaired and a lot of people are visiting from other places. It means I can sell more and earn more,” says Dalci Cardoso da Silva, who runs a leather shoe stall.

He says this is necessary because when he was young, Belém was “beautiful, well-kept, well cared for”, but it has since been “abandoned” and “neglected” with “little interest from the ruling class”.

João Alexandre Trindade da Silva, who sells Amazonian herbal medicines in the market, acknowledges that all construction work can cause problems, but he felt the future impact would be worth it.

“We hope the discussions aren’t just on paper and become real actions. And the measures, the decisions taken, really are put into practice so that the planet can breathe a little better, so that the population in the future will have a little cleaner air.”

That will be the hope of world leaders too who choose to attend the COP30 summit.

Scrutiny is growing over whether flying thousands of them across the world, and the infrastructure required to host them, is undermining the cause.

Taken From BBC News

https://www.bbc.com/news/articles/c9vy191rgn1o