̽��ֱ�� of Cambridge - Department of Earth Sciences

Thriving Antarctic ecosystems found following iceberg calving

Anonymous — Tue, 25 Mar 2025 10:22:45 +0000

An international team of scientists have uncovered a thriving underwater ecosystem off the coast of Antarctica that had never before been accessible to humans.

̽��ֱ��team, including researchers from the ̽��ֱ�� of Cambridge, were working in the Bellingshausen Sea off the coast of Antarctica when a massive iceberg broke away from the George VI Ice Shelf in January of this year.

̽��ֱ��team, on board Schmidt Ocean Institute’s R/V Falkor (too), changed their plans and reached the newly exposed seafloor 12 days later, becoming the first to investigate the area.

Their expedition was the first detailed study of the geology, physical oceanography, and biology beneath such a large area once covered by a floating ice shelf. ̽��ֱ��A-84 iceberg was approximately 510 square kilometres (209 square miles) in size, and revealed an equivalent area of seafloor when it broke away from the ice shelf.

"We seized upon the moment, changed our expedition plan, and went for it so we could look at what was happening in the depths below," said expedition co-chief scientist Dr Patricia Esquete from the ̽��ֱ�� of Aveiro, Portugal. "We didn't expect to find such a beautiful, thriving ecosystem. Based on the size of the animals, the communities we observed have been there for decades, maybe even hundreds of years.”

Using Schmidt Ocean Institute’s remotely operated vehicle, ROV SuBastian, the team observed the deep seafloor for eight days and found flourishing ecosystems at depths as great as 1300 meters.

Their observations include large corals and sponges supporting an array of animal life, including icefish, giant sea spiders, and octopus. ̽��ֱ��discovery offers new insights into how ecosystems function beneath floating sections of the Antarctic ice sheet.

Little is known about what lies beneath Antarctica’s floating ice shelves. In 2021, British Antarctic Survey researchers first reported signs of bottom-dwelling life beneath the Filchner-Ronne ice shelf in the Southern Weddell Sea. ̽��ֱ��current expedition was the first to use an ROV to explore this remote environment.

̽��ֱ��team was surprised by the significant biomass and biodiversity of the ecosystems and suspect they have discovered several new species.

Deep-sea ecosystems typically rely on nutrients from the surface slowly raining down to the seafloor. For centuries, the ecosystems under the ice shelf have been covered by ice almost 150 metres thick, completely cutting them off from surface nutrients. " ̽��ֱ��fact that we found long-living species suggests that the lateral transport, which mostly consists of glacial meltwater from the ice shelf, could be the source of the nutrients to sustain the life we found," said team member Dr Laura Cimoli, from Cambridge’s Department of Applied Mathematics and Theoretical Physics.

̽��ֱ��newly exposed Antarctic seafloor also allowed the team, with scientists from Portugal, the United Kingdom, Chile, Germany, Norway, New Zealand, and the United States, to gather critical data on the past behaviour of the larger Antarctic ice sheet. ̽��ֱ��ice sheet has been shrinking and losing mass over the last few decades due to climate change.

“ ̽��ֱ��ice loss from the Antarctic Ice Sheet is a major contributor to sea level rise worldwide,” said expedition co-chief scientist Sasha Montelli of ̽��ֱ�� College London (UCL). “Our work is critical for providing longer-term context of these recent changes, improving our ability to make projections of future change — projections that can inform actionable policies. We will undoubtedly make new discoveries as we continue to analyse this data.”

“We were thrilled by the opportunity to explore the newly exposed seafloor,” said team member Dr Svetlana Radionovskaya from Cambridge’s Department of Earth Sciences. “ ̽��ֱ��research will provide key insights into ice sheet dynamics, oceanography and sub-ice shelf ecosystems. At a time when the West Antarctic Ice Sheet is melting at an alarming rate, understanding these dynamics and their impacts is crucial.”

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̽��ֱ��oceanography team, led by Cimoli in collaboration with the ̽��ֱ�� of East Anglia and the British Antarctic Survey, used autonomous underwater vehicles to characterise the ocean circulation of the region and study the impacts of glacial meltwater on the physical and chemical seawater properties. "Antarctica and the Southern Ocean are a nexus point for ocean circulation, so changes that happen around Antarctica can affect global ocean circulation and global climate," said Cimoli.

̽��ֱ��researchers are also investigating how the iceberg calving event has contributed to mix the upper ocean, not just in the recently exposed area, but also further downstream as the iceberg floats away. As the giant iceberg drifts, it can generate turbulence that mixes water properties and could potentially mix the deep nutrient-rich water with the surface waters, fuelling biological productivity.

̽��ֱ��expedition was part of Challenger 150, a global cooperative focused on deep-sea biological research and endorsed by the Intergovernmental Oceanographic Commission of UNESCO (IOC/UNESCO) as an Ocean Decade Action.

“ ̽��ֱ��science team was originally in this remote region to study the seafloor and ecosystem at the interface between ice and sea,” said Schmidt Ocean Institute Executive Director, Dr Jyotika Virmani. “Being right there when this iceberg calved from the ice shelf presented a rare scientific opportunity. Serendipitous moments are part of the excitement of research at sea – they offer the chance to be the first to witness the untouched beauty of our world.”

Svetlana Radionovskaya is a Junior Research Fellow at Queens’ College, Cambridge. Laura Cimoli is a Research Fellow at the Institute of Computing for Climate Science, Department of Applied Mathematics and Theoretical Physics at the ̽��ֱ�� of Cambridge.

Adapted from a media release by the Schmidt Ocean Institute.

Inset image: Dr Cimoli (right) and Dr Meyer (UEA, left) prepare an underwater glider for deployment. Credit: Alex Ingle/Schmidt Ocean Institute.

Scientists explore a seafloor area newly exposed by iceberg A-84; discover vibrant communities of ancient sponges and corals.

ROV SuBastian / Schmidt Ocean Institute

Deep-sea coral at a depth of 1200 metres

̽��ֱ��text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

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̽��ֱ��coral whisperer

lkm37 — Tue, 25 Feb 2025 09:41:11 +0000

Duygu Sevilgen has built a coral lab in the basement of an old Zoology building. Here, 10 experimental tanks host multicoloured miniature forests, with each tank representing a different marine environment. Duygu uses extremely small sensors to record the fine details of coral skeletons and listen to their dialogue with algae. In doing so, she determines how much change corals can bear, and improves our chances of saving them in the wild.

̽��ֱ��tale of the tomb of Thutmose II

fpjl2 — Mon, 24 Feb 2025 12:15:24 +0000

Cambridge ̽��ֱ��'s Dr Judith Bunbury is Deputy Mission Director of the archaeological project in the Theban Mountain area that found the lost tomb of Thutmose II.

Into the underworld: the mountains beneath our feet

lkm37 — Tue, 14 Jan 2025 10:41:16 +0000

Sanne Cottaar is Professor of Global Seismology in Earth Sciences. She wants to understand Earth’s inner structure: how it shaped the surface and allowed life to form.

Scientists warn of ‘invisible threat’ of microplastics as global treaty nears completion

sc604 — Tue, 26 Nov 2024 10:50:47 +0000

Even if global production and pollution of new plastic is drastically reduced, scientists, writing in the journal Nature Communications, say that legacy plastics, the billions of tonnes of waste already in the environment, will continue to break down into tiny particles called microplastics for decades or centuries.

These fragments contaminate oceans, land, and the air we breathe, posing risks to marine life, food production and human health.

̽��ֱ��researchers – from the ̽��ֱ�� of Cambridge, GNS Science in New Zealand and ̽��ֱ��Ocean Cleanup in ̽��ֱ��Netherlands – say the problem lies in a gap between ambition and action, called the fragmentation gap.

At a meeting this week in Busan, South Korea, the Intergovernmental Negotiating Committee on Plastic Pollution is meeting to finalise the Global Plastics Treaty, the first legally binding treaty to tackle plastic pollution.

While the treaty’s initial discussions highlight prevention of plastic pollution, the researchers say it largely overlooks the need to remove existing waste. This omission means microplastics will continue to accumulate, even if plastic pollution slows.

“ ̽��ֱ��treaty is aiming to eliminate plastic pollution by 2040, but this goal is unlikely without stronger action,” said co-author Zhenna Azimrayat-Andrews, a PhD student at Cambridge’s Department of Earth Sciences. “Even with a sharp reduction in plastic entering the ocean, existing debris will split into smaller pieces and persist for centuries.”

These microplastics have already infiltrated marine ecosystems and are harming marine ecosystems, degrading commercial seafood quality, and disrupting critical ocean processes.

̽��ֱ��researchers argue that plastic clean-up efforts must be prioritised alongside reduction targets. Strategies to remove plastics from terrestrial and marine environments, such as those targeting pollution in beaches and rivers, could help prevent microplastics from forming. In fact, a 3% annual removal of legacy plastic, combined with aggressive reduction measures, could significantly curb future contamination, they say.

Without action to address legacy plastic, the treaty risks leaving behind a long-lasting problem for marine life and future generations. Experts are calling for clean-up efforts to become an equal pillar of the treaty, alongside prevention and recycling.

As world leaders gather to negotiate the treaty this week, the spotlight is on their ability to craft a comprehensive plan that doesn't just slow pollution but also begins to reverse the damage that has already been done.

Reference:
Karin Kvale, Zhenna Azimrayat Andrews & Matthias Egger. ‘Mind the fragmentation gap.’ Nature Communications (2024). DOI: 10.1038/s41467-024-53962-3

As the UN meets this week to finalise the Global Plastics Treaty, researchers warn that the agreement could fail to address one of the biggest threats to marine environments—microplastics.

Alistair Berg via Getty Images

Researcher holding small pieces of micro plastic pollution washed up on a beach

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Bird brain from the age of dinosaurs reveals roots of avian intelligence

sc604 — Wed, 13 Nov 2024 14:20:58 +0000

A ‘one of a kind’ fossil discovery could transform our understanding of how the unique brains and intelligence of modern birds evolved, one of the most enduring mysteries of vertebrate evolution.

How did the building blocks of life arrive on Earth?

sc604 — Fri, 11 Oct 2024 18:00:00 +0000

Volatiles are elements or compounds that change into vapour at relatively low temperatures. They include the six most common elements found in living organisms, as well as water. ̽��ֱ��zinc found in meteorites has a unique composition, which can be used to identify the sources of Earth’s volatiles.

̽��ֱ��researchers, from the ̽��ֱ�� of Cambridge and Imperial College London, have previously found that Earth’s zinc came from different parts of our Solar System: about half came from beyond Jupiter and half originated closer to Earth.

“One of the most fundamental questions on the origin of life is where the materials we need for life to evolve came from,” said Dr Rayssa Martins from Cambridge’s Department of Earth Sciences. “If we can understand how these materials came to be on Earth, it might give us clues to how life originated here, and how it might emerge elsewhere.”

Planetesimals are the main building blocks of rocky planets, such as Earth. These small bodies are formed through a process called accretion, where particles around a young star start to stick together, and form progressively larger bodies.

But not all planetesimals are made equal. ̽��ֱ��earliest planetesimals that formed in the Solar System were exposed to high levels of radioactivity, which caused them to melt and lose their volatiles. But some planetesimals formed after these sources of radioactivity were mostly extinct, which helped them survive the melting process and preserved more of their volatiles.

In a study published in the journal Science Advances, Martins and her colleagues looked at the different forms of zinc that arrived on Earth from these planetesimals. ̽��ֱ��researchers measured the zinc from a large sample of meteorites originating from different planetesimals and used this data to model how Earth got its zinc, by tracing the entire period of the Earth’s accretion, which took tens of millions of years.

Their results show that while these ‘melted’ planetesimals contributed about 70% of Earth’s overall mass, they only provided around 10% of its zinc.

According to the model, the rest of Earth’s zinc came from materials that didn’t melt and lose their volatile elements. Their findings suggest that unmelted, or ‘primitive’ materials were an essential source of volatiles for Earth.

“We know that the distance between a planet and its star is a determining factor in establishing the necessary conditions for that planet to sustain liquid water on its surface,” said Martins, the study’s lead author. “But our results show there’s no guarantee that planets incorporate the right materials to have enough water and other volatiles in the first place – regardless of their physical state.”

̽��ֱ��ability to trace elements through millions or even billions of years of evolution could be a vital tool in the search for life elsewhere, such as on Mars, or on planets outside our Solar System.

“Similar conditions and processes are also likely in other young planetary systems,” said Martins. “ ̽��ֱ��roles these different materials play in supplying volatiles is something we should keep in mind when looking for habitable planets elsewhere.”

̽��ֱ��research was supported in part by Imperial College London, the European Research Council, and UK Research and Innovation (UKRI).

Reference:
Rayssa Martins et al. ‘Primitive asteroids as a major source of terrestrial volatiles.’ Science Advances (2024). DOI: 10.1126/sciadv.ado4121

Researchers have used the chemical fingerprints of zinc contained in meteorites to determine the origin of volatile elements on Earth. ̽��ֱ��results suggest that without ‘unmelted’ asteroids, there may not have been enough of these compounds on Earth for life to emerge.

Rayssa Martins/Ross Findlay

An iron meteorite from the core of a melted planetesimal (left) and a chondrite meteorite, derived from a ‘primitive’, unmelted planetesimal (right).

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Highly-sensitive beaks could help albatrosses and penguins find their food

sc604 — Wed, 18 Sep 2024 00:09:46 +0000

Researchers have discovered that seabirds, including penguins and albatrosses, have highly-sensitive regions in their beaks that could be used to help them find food. This is the first time this ability has been identified in seabirds.