Category: 7. Science

Astronomers just caught a celestial sneak peek at how solar systems are born, and it starts with something delightfully small: space pebbles.

Around two young stars, DG Tau and HL Tau, tiny grains are gathering in vast pancake-like clouds called protoplanetary discs, stretching to Neptune-like distances. These pebbles are nature’s building blocks, slowly clumping into massive worlds over millions of years, just like how Jupiter, Saturn, and even Earth formed 4.5 billion years ago.

These stars are located approximately 450 light-years away, quietly forming miniature versions of our cosmic neighborhood. It’s like watching the universe sketch out its next masterpiece, one pebble at a time.

Astronomers peering into the deep space nurseries around young stars DG Tau and HL Tau have uncovered something spectacular: enormous reservoirs of planet-building pebbles stretching as far out as Neptune’s orbit, and possibly beyond. It’s like stumbling on a galactic blueprint for mega solar systems.

Stellar winds help dust grains grow into planet-building pebbles

Using the e-MERLIN telescope network, scientists created a detailed map of DG Tau’s disc, a tilted swirl of gas and dust. In this interstellar pancake, Pebble-sized clumps are gathering like early ingredients for world-making. The disc tilts southeast to northwest, showing a graceful spread of material and outflows from the star streak northeast and southwest, a sign of stellar winds shaping the neighborhood.

Astronomers are taking on a cosmic detective mission with a bold new initiative called PEBBLeS, led by Professor Jane Greaves of Cardiff University. Their goal? To search the skies for rocky belts around young stars, places where new planets are being born.

By imaging these dusty zones, the team hopes to discover how often and where planets form around stars destined to become suns like our own.

To do this, they’re using e-MERLIN, a UK-wide radio telescope super-array comprising seven dishes that span 217 kilometers. Linked by lightning-fast fiber optics and coordinated from the iconic Jodrell Bank Observatory, e-MERLIN has the unique precision needed.

Finding a cosmic fog within shattered intergalactic ‘pancakes’

The observations enabled astronomers to pinpoint the region where solid material accumulates in the discs. Hence, it offers clues on one of the earliest stages of planet formation.

Since the 1990s, astronomers have discovered thousands of fully-formed planets and swirling disks of space dust around young stars. These discs, packed with grains like cosmic sand, are the raw material for building planets.

Early on, when the grains are spread out (sometimes across areas as large as Jupiter’s orbit), they’re easy to spot using infrared or submillimeter telescopes, such as ALMA.

As the grains start to clump into planets, their surface area decreases. That makes them harder to detect; the more planet-like they become, the less visible they become.

To spot the baby building blocks of planets, those centimeter-sized pebbles quietly gathering in young star systems, scientists need a telescope tuned to just the right wavelength. Enter e-MERLIN, the UK’s radio interferometer, which observes at 4 cm, the sweet spot for detecting these tiny future worlds.

Using e-MERLIN, researchers discovered that DG Tau’s disc is brimming with pebbles even out to Neptune-like orbits. Also, there’s a similar belt of planetary seeds forming around HL Tau.

These dusty discs aren’t just signs of planets-to-be; they’re early blueprints for solar systems that might be even bigger than our own.

Looking ahead, the massive Square Kilometre Array (SKA) in South Africa and Australia will take this to the next level. With greater sensitivity and scale, SKA will unveil thousands of discs across the galaxy. Starting in 2031, SKA-Mid will begin verifying science and dive into studying hundreds of planetary systems.

As Dr. Hesterly put it, e-MERLIN showed what’s possible; SKA will explore the galaxy’s wild imagination.

Astronomers unveiled a striking new view of the interstellar visitor 3I/ATLAS on its journey toward the inner solar system.

The Gemini North telescope in Hawai‘i captured the newfound comet passing through our cosmic neighborhood, about 290 million miles (465 million kilometers) from Earth.

New research suggests that as many as 100 galaxies, too faint to be detected by current instruments, could be orbiting the Milky Way. These potential galaxies, dubbed “orphan” galaxies, may have remained hidden due to their low brightness.

The discovery was made by cosmologists at Durham University in England, who used an advanced technique that combines the world’s highest-resolution supercomputer simulations with detailed mathematical modelling, ABC News reported.

The findings were presented at the Royal Astronomical Society’s National Astronomy Meeting in Durham on Friday.

The simulations revealed clues pointing to the existence of numerous unseen satellite galaxies closely surrounding our own. If confirmed, this discovery could reshape our understanding of the Milky Way’s structure and the number of galaxies in its immediate vicinity.

Isabel Santos-Santos, the lead researcher at Durham University’s Institute for Computational Cosmology, said: “We know the Milky Way has some 60 confirmed companion satellite galaxies, but we think there should be dozens more of these faint galaxies orbiting around the Milky Way at close distances.”

If telescopes detect these galaxies, it would strongly support the Lambda Cold Dark Matter theory, the leading model of cosmology explaining how galaxies form and the large-scale structure of the universe, researchers said.

According to the model, galaxies form at the centres of massive clumps of dark matter known as halos. It also proposes that just 5% of the Universe is made up of ordinary matter, 25% is cold dark matter, and 70% is dark energy.

Most galaxies in the universe are low-mass dwarf galaxies that orbit larger ones like the Milky Way, astronomers said.

These satellite galaxies have long challenged the Lambda Cold Dark Matter (ΛCDM) model, which predicts more companions than previous simulations could explain. However, the new technique enabled researchers to trace the number, spread, and characteristics of these faint “orphan” galaxies more accurately.

The model provides a “clear illustration” of the power of physics and mathematics, said Carlos Frenk, a co-researcher at the Institute for Computational Cosmology.

Current simulations lack the resolution to study faint satellite galaxies and their dark matter halos, leading to gaps in data, researchers said. If the predictions hold true, it would strengthen the ΛCDM model.

Dead marine giants do not fade quietly. After scavengers strip away the flesh, their sinking bones become banquet halls for specialized worms. These worms drill through the skeleton and siphon its last reserves of fat and protein.

A new survey of those ancient drill marks has identified seven distinct burrow types, revealing just how long these bone-eaters have shaped life on the seafloor.

The study was led by Ph.D. student Sarah Jamison-Todd in collaboration with curator Marc Jones and colleagues at the Natural History Museum of London.

By combing through more than 130 Cretaceous reptile fossils, the team identified distinctive tunnel patterns in the bones. They then scanned the best examples with micro-CT and linked each pattern to a unique “ichnospecies.”

This bolsters evidence that the living bone-eating worms known as Osedax descend from a lineage at least 100 million years old.

Worms feast on sunken bones

Modern Osedax worms colonize whale falls all the way from polar shallows to abyssal plains. Mouthless and gutless, they rely on symbiotic bacteria to digest bone, feeding through root-like filaments and leaving behind bulbous cavities.

Similar traces were found in fossil skeletons of plesiosaurs, ichthyosaurs, turtles, and early whales, hinting at a deep evolutionary history.

“We haven’t found anything else that makes a similar burrow to these animals,” Jamison-Todd explained. “As the ancient bores are so similar to modern Osedax species, and we don’t have body fossils to contradict us, we assume that they were made by the same or a similar organism.”

“It shows the bone-eating worms are part of a lineage that stretches back at least to the Cretaceous, and further. We can see how the diversity of bone-eating worms changes across millions of years.”

Historic bones, new insights

Pinpointing that history meant first nailing down the ages of century-old specimens. “Some of these were collected in the 1800s, and the information on them can be very brief, so it’s difficult to know exactly where they’re from,” Jones said.

“We focused on specimens from the Chalk of the U.K., as our colleagues have been working on better understanding these Cretaceous ecosystems using museum collections.”

“They’re also working to date fossils of an unknown age. By using the remains of small organisms that make up the Chalk itself, we were able to date the fossils to more precise time slices of the Cretaceous Period.”

Worm trails hidden in ancient bones

Armed with refined dates, the researchers searched for borehole entrances scarcely wider than a needle.

“We examined over 130 different fossils for signs of bone-eating worm burrows,” Jamison-Todd said. “However, not all fossils which look like they’ve been bored into by these worms have been – it could have been caused by different animals or environmental weathering.”

“The only way to really confirm this is to put the fossils under a CT scanner. This allows us to create 3D reconstructions of the inside of the bone and see the different patterns that have been left behind.”

The scans revealed meandering tubes, lobed pockets, and tree-like chambers hidden beneath the surface.

Each shape repeated across multiple specimens, convincing the researchers that they marked discrete behavioral blueprints rather than random damage.

Naming the ancient burrow types

Six new burrow types from the Chalk and one from Belgium form a seven-member ichnospecies roster. The names draw on both form and inspiration.

Osspecus arboreum branches like a sapling inside shattered ribs. Osspecus morsus gnaws through tooth roots, its Latin epithet recalling a bite.

The name Osspecus eunicefootia honors Eunice Newton Foote, the overlooked pioneer who first linked atmospheric carbon dioxide to global warming.

Each label provides a shorthand for paleontologists who stumble on similar traces elsewhere. This lets them slot new data into a growing catalog of deep-sea recyclers.

Diversification of bone-eating worms

Bone falls create oases on the otherwise sparse ocean floor, feeding entire communities from bacteria to crabs. Charting how bone-worms diversified illuminates both those ecosystems and the broader carbon cycle.

“There are many more examples of boring that haven’t yet been named from both ancient and modern bone-eating worms,” Jamison-Todd said. “In fact, some bores from the Cretaceous appear to be similar to ones that are still made today.”

“Finding out whether these burrows are made by the same species, or are an example of convergent evolution, will give us a much better idea of how these animals have evolved, and how they have shaped marine ecosystems over millions of years.”

A window into lost oceans

Because Osedax bores only soft, fatty bone, their presence proves that large carcasses once littered even shallow Cretaceous seas. These remains came first from marine reptiles, and later from early whales.

The worms’ longevity also suggests that whenever vertebrate giants die, life quickly evolves to recycle them.

By giving formal names to the delicate tunnels etched in chalky ribs and teeth, the study turns museum drawers into time-lapse images of ecological succession.

Each burrow is a snapshot of a feast that ended eons ago yet still whispers of the unseen engineers who keep nutrients moving through the dark ocean floor.

Image credit: Sarah Jamison-Todd

The study is published in the journal PLOS One.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–

Enabling & Support

17/07/2025
112 views
3 likes

Light can also be left or right ‘handed’. When a light beam is circularly polarized, its electric field corkscrews through space in either a left-handed or right-handed spiral. Because chiral structures interact differently with these two types of twisted light beams, shining a circularly polarized light on a sample – and comparing how much of each twist is absorbed, reflected, or delayed – lets scientists read out the sample’s own handedness. However, this effect is extremely weak, which makes precise control of chirality an essential but challenging task.

Now, scientists from the Bionanophotonic Systems Laboratory in EPFL’s School of Engineering have collaborated with those in Australia to create artificial optical structures called metasurfaces: 2D lattices composed of tiny elements (meta-atoms) that can easily tune their chiral properties. By varying the orientation of meta-atoms within a lattice, scientists can control the resulting metasurface’s interaction with polarized light.

“Our ‘chiral design toolkit’ is elegantly simple, and yet more powerful than previous approaches, which tried to control light through very complex meta-atom geometries. Instead, we leverage the interplay between the shape of the meta-atom and the symmetry of the metasurface lattice,” explains Bionanophotonics Lab head Hatice Altug.

The innovation, which has potential applications in data encryption, biosensing, and quantum technologies, has been published in Nature Communications.

An invisible, dual layer watermark

The team’s metasurface, made of germanium and calcium difloride, presents a gradient of meta-atoms with orientations that vary continuously along a chip. The shape and angles of these meta-atoms, as well as the lattice symmetry, all work together to tune the response of the metasurface to polarized light.

In a proof-of-concept experiment, the scientists encoded two different images simultaneously on a metasurface optimized for the invisible mid-infrared range of the electromagnetic spectrum. For the first image of an Australian cockatoo, the image data were encoded in the size of the meta-atoms – which represented pixels – and decoded with unpolarized light. The second image was encoded using the orientation of the meta-atoms so that, when exposed to circularly polarized light, the metasurface revealed a picture of the iconic Swiss Matterhorn.

“This experiment showcased our technique’s ability to produce a dual layer ‘watermark’ invisible to the human eye, paving the way for advanced anticounterfeiting, camouflage and security applications,” says Bionanophotonics Systems Lab researcher Ivan Sinev.

Beyond encryption, the team’s approach has potential applications for quantum technologies, many of which rely on polarized light to perform computations. The ability to map chiral responses across large surfaces could also streamline biosensing.

“We can use chiral metastructures like ours to sense, for example, drug composition or purity from small-volume samples. Nature is chiral, and the ability to distinguish between left- and right-handed molecules is essential, as it could make the difference between a medicine and a toxin,” says Bionanophotonic Systems Lab researcher Felix Richter.

A fossil found on Vancouver Island in 1988 looked like a typical long‑necked marine reptile, yet every expert who studied Traskasaura sandrae left with new questions.

Scientists have now confirmed that the 39‑foot creature, which lived about 85 million years ago, represents an entirely new species with a hunting style never before documented in its family.

“It has a very odd mix of primitive and derived traits,” said Professor F. Robin O’Keefe of Marshall University, whose group named the predator Traskasaura sandrae. He led the team that solved the puzzle.

Digging up Traskasaura sandrae

The first bones came from the Haslam Formation, a shale layer laid down when shallow seas covered what is now British Columbia.

Community volunteers spent three summers freeing the skeleton, which included more than fifty tightly linked neck vertebrae.

Additional material surfaced during highway construction and a separate riverbank dig, bringing the total to three individuals.

Together they revealed a full neck, torso, limbs, and the crushing teeth that tipped researchers off to an unusual feeding strategy.

Neck was built for ambush

Most elasmosaurs relied on sideways sweeps to grab fish, but the team noticed that the neck joints of Traskasaura sandrae allow smooth downward flexion.

That range, paired with robust shoulder muscles, supports the idea that the reptile hovered above prey before plunging like a heron.

Each cervical rib points slightly forward, a feature seen only in a handful of southern-hemisphere relatives. The forward slant stiffened the neck during a rapid dive, preventing whiplash while the head shot toward a target below.

Clues in the shoulders and teeth

The glenoid cavity, where the humerus meets the body, faces partly downward instead of purely sideways. That tilt aimed the paddles to push water straight back and down, giving the animal a quick vertical burst.

“Its teeth were ideal for crushing,” explained O’Keefe. One preserved crown still holds fragments of broken shell.

Heavy conical teeth, round in cross‑section and ringed by deep grooves, suggest a diet of shelled ammonites common in the same rocks. 

Life in the late Cretaceous pacific

During the Late Cretaceous, Vancouver Island sat around the latitude of present‑day Oregon, edged by warm fore‑arc basins teeming with mollusks and early sharks.

Ammonite fossils from the Pachydiscus group dominate these beds, matching the menu implied by the reptile’s dentition.

The sea also hosted sleek mosasaurs and blade‑toothed birds, yet Traskasaura filled a separate niche: the slow‑motion stalker that attacked from above.

Its 12‑foot paddles produced short bursts rather than long chases, conserving energy in nutrient‑rich but cooler northern waters.

Rewriting the plesiosaur family tree

Although classified as a plesiosaur, the newcomer sits near the base of the elasmosaur branch. The phylogenetic work by O’Keefe and colleagues shows it split early from southern cousins such as Aristonectes yet later evolved similar shoulder joints, an example of convergent evolution.

That finding warns against sorting species by one standout trait. Neck length alone once grouped nearly every long‑necked reptile together, but limb and girdle details tell a more nuanced story about how different lineages hunted and swam.

Traskasaura sandrae anatomy

The first fossil puzzled paleontologists because it blended features usually found in different branches of the plesiosaur family.

Its skull and teeth matched primitive species, but its shoulders and forelimbs looked like more specialized animals from the southern hemisphere.

Researchers initially hesitated to call it a new species because many of the bones were fragmented or eroded. It wasn’t until a second, better-preserved skeleton was uncovered that scientists could confidently identify the creature’s unique traits and confirm its identity.

What the find means today

The Courtenay and District Museum now displays the best skeleton, giving British Columbia a provincial fossil with unmistakable local flavor.

School groups can stand beside vertebrae longer than their hands and imagine a reptile that prowled the same coastal waters where orcas swim.

“Our new research finally solves this mystery,” added O’Keefe.

Beyond regional pride, the study highlights how community collectors, careful curation, and modern scans can unlock decades‑old mysteries. The creature’s hybrid anatomy will keep fueling debates about function and evolution for years. 

How Traskasaura sandrae got its name

The genus name Traskasaura honors Michael and Heather Trask, the father-daughter team who found the original fossil along the Puntledge River in 1988. The name combines their surname with the Greek word sauros, meaning lizard.

The species name sandrae was chosen in memory of Sandra Lee O’Keefe, a Pacific Northwest native and advocate for breast cancer awareness.

This tribute mirrors the legacy of Elizabeth Nicholls, a paleontologist who helped identify the fossils in 2002.

The study is published in the Journal of Systematic Palaeontology.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–

Evolution often follows curious paths, especially when it comes to food. Over the past 100 million years, mammals have explored an incredible range of diets.

Some mammals graze on grass, others hunt prey, and a few even sip tree sap or dive for krill. But one of the strangest dietary turns comes from species that eat and depend deeply on ants and termites.

This peculiar choice may seem limiting, even risky. Yet, it has driven major transformations in anatomy, behavior and even survival strategies.

Dietary changes for mammals

According to new research, mammals evolved ant and termite-only diets at least 12 separate times over 66 million years.

This shift, called myrmecophagy, followed the dinosaur extinction. It allowed ants and termites to thrive and opened a new food niche for mammals.

“There’s not been an investigation into how this dramatic diet evolved across all known mammal species until now,” said Phillip Barden of the New Jersey Institute of Technology (NJIT).

“This work gives us the first real roadmap, and what really stands out is just how powerful a selective force ants and termites have been over the last 50 million years – shaping environments and literally changing the face of entire species.”

How mammals adapted to eat ants

Over 200 mammal species consume ants or termites occasionally. But just 20, like pangolins and anteaters, rely on them completely.

These true myrmecophages evolved long, sticky tongues and powerful claws. Many even lost their teeth.

To track this trend, the researchers collected diet records from 4,099 species. These came from nearly 100 years of scientific papers, field notes and conservation reports.

“Compiling dietary data for nearly every living mammal was daunting, but it really illuminates the sheer diversity of diets and ecologies in the mammalian world,” said Thomas Vida from the University of Bonn.

Small ant-eaters need to eat huge numbers to survive. Numbats eat around 20,000 termites daily. Aardwolves can eat over 300,000 ants in one night.

Understanding anteaters – the basics

Anteaters belong to the suborder Vermilingua, which literally means “worm tongue” – an apt name, since their tongues can extend up to two feet and flick in and out of their mouths up to 160 times per minute.

Modern-day anteaters don’t have teeth, so they rely on their sticky tongues and powerful stomachs to digest the thousands of ants and termites they consume daily.

Their long, tubular snouts house an excellent sense of smell, which is key to locating insect nests in the wild.

Despite their name, anteaters don’t just eat ants. They also snack on termites, and they’re careful not to destroy an entire colony – they’ll feed for just a minute or two before moving on, ensuring the nest can recover for future visits.

Giant anteaters, like the one pictured in this article, can grow over 7 feet long from nose to tail. These solitary animals roam grasslands and rainforests across Central and South America.

With their shaggy coats and slow, deliberate movements, they might seem awkward – but they’re incredibly strong, especially in their forelimbs, which they use to rip open tough termite mounds or defend themselves from predators.

The rise of ants and termites

The team grouped species by diet. From ant-only eaters to generalists. Then they mapped these onto a mammal family tree and ran evolutionary models.

The experts found at least 12 independent shifts to strict myrmecophagy. These happened in marsupials, monotremes and placental mammals. But not evenly. Some groups showed more change than others.

The researchers also looked back 145 million years to study the rise of ant and termite colonies. During the Cretaceous, ants and termites were rare. By the Miocene, 23 million years ago, they made up over a third of insect populations.

“It’s not clear exactly why ants and termites both took off around the same time. Some work has implicated the rise of flowering plants, along with some of the planet’s warmest temperatures during the Paleocene-Eocene Thermal Maximum about 55 million years ago,” said Barden.

“What is clear is that their sheer biomass set off a cascade of evolutionary responses across plants and animals.”

Ant-eating mammals rarely change diets

Myrmecophagy arose more often from insect-eating ancestors than from carnivores. But surprisingly, carnivores like dogs and bears made the switch several times too.

“That was a surprise,” Barden said. “Making the leap from eating other vertebrates to consuming thousands of tiny insects daily is a major shift.”

Once a mammal becomes a myrmecophage, it rarely reverts. Only one genus, Macroscelides, the elephant shrews, ever switched back to a broader diet after specializing.

Eight of the twelve times mammals evolved to eat only ants or termites, just one species survived each time.

This limited survival suggests that highly specialized creatures, while successful in their niche, may face a greater risk of extinction due to changing environments, food scarcity, or habitat disruption over time.

Ant-eaters survive as insects spread

“In some ways, specializing on ants and termites paints a species into a corner,” Barden said. But for now, these specialists thrive.

Ants and termites now outweigh all wild mammals combined. Climate change favors species with massive colonies.

This shift may help ant- and termite-eating mammals, known as myrmecophages, survive and thrive. Their specialized diet could become a surprising advantage in a world increasingly ruled by social insects.

“If you can’t beat them, eat them,” Barden said. That idea, repeated across millions of years, has changed the face of mammals again and again.

The study is published in the journal Evolution.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–

Tiny bits of organic matter bobbing at the ocean’s surface appear to help clouds freeze in some of the most pristine air on Earth.

New research shows that complex sugar molecules shed by marine microbes can trigger ice formation in cloud droplets across the vast Southern Ocean. This happens right in the temperature range that governs how long bright, cooling clouds survive and how much sunlight they bounce back to space.

The work draws on years of field campaigns, lab tests, and computer modeling led by scientists at the Leibniz Institute for Tropospheric Research (TROPOS) and its partners.

It helps explain why climate models have struggled to match observed cloud brightness over remote southern seas. In these regions, dust is scarce and human-made pollution is low.

Clouds need help to freeze

Clouds do not freeze on their own; they need ice-nucleating particles (INPs). These microscopic seeds coax liquid droplets into ice. The kind of particle that dominates changes with temperature.

In the cleaner air around Antarctica and the Southern Ocean, INP levels are tiny. Even small shifts can strongly affect cloud reflectivity, precipitation, and lifetime.

Getting the mix right in climate models is essential for predicting global warming.

A sugar spike reveals a clue

Scientists have long suspected marine biology as a source of INPs, but the actual substances remained mysterious. A turning point came during the 2017 Polarstern expedition PS106.

“During the Polarstern expedition PS106 in 2017, we observed increased glucose concentrations in Arctic samples and concluded this glucose could be an indicator of ice nuclei in seawater,” said senior author Sebastian Zeppenfeld from TROPOS.

“The monosaccharide glucose is a degradation product of polysaccharides. It was therefore obvious to us that polysaccharides could be the missing piece of the puzzle.”

Ocean sugars and freezing clouds

To test the idea, researchers collected material from the ocean’s surface microlayer. This living film teems with bacteria, algae, diatoms, fungi, protists, viruses, and more. Researchers had largely overlooked marine fungi as possible ice starters.

Study co-author Susan Hartmann from TROPOS examined ice nucleation in the laboratory using the INDA (Ice Nucleation Droplet Array) droplet freezing test.

“We investigated the ice nucleation of marine polysaccharides derived from marine fungi and protist, as well as commercially available standard polysaccharides,” she said.

Those droplet-freezing experiments produced the first temperature‑resolved data showing how many ice nuclei these marine polysaccharides generate.

The results fill a key gap: between roughly -15°C (5°F) and -20°C (-4°F), the ocean sugars could account for nearly all biologically driven ice formation in cloud droplets.

Cloud models get missing ice link

Earlier work had shown that proteins tend to initiate freezing in relatively “warm” clouds (above about 28°F), while mineral dust dominates in very cold clouds (below -4°F).

But the Southern Hemisphere offers limited dust sources. Many mixed-phase clouds linger in the middle range – exactly where the new study shows marine polysaccharides are most potent.

Study lead author Roland Schrödner from TROPOS analyzed the data using the TM5 global atmospheric chemistry transport model.

“In our simulations, we were able to show that at -15 to -16 degrees Celsius (5 to 3°F), the polysaccharides over the gigantic areas of the oceans in the clean Southern Hemisphere are probably the most important ice nuclei,” said Schrödner.

“They contribute more to ice formation than mineral dust emitted from the deserts, which is the main type of ice nuclei in climate models. This is a new and important finding for climate models.”

Years of data point to sugars

The study knits together aerosol microphysics, atmospheric chemistry, and global modeling groups at TROPOS.

Polysaccharide concentrations had been sampled during multiple expeditions: the Spanish Antarctic PI‑ICE mission, the German Arctic PASCAL/PS106 cruises, the tropical Atlantic MarParCloud campaign, and long‑term measurements on Spitsbergen.

Only by combining those datasets with lab freezing tests and model simulations could the team quantify the climatic punch of marine sugars.

Next steps for cloud ice research

If nations succeed in cutting man‑made emissions, natural aerosol particles will matter even more for cloud behavior. Clean‑air regions respond sharply to even small aerosol changes, making the Southern Hemisphere a prime natural laboratory.

Beginning July 2025, the HALO‑South aircraft mission – led by TROPOS – will probe clouds, aerosols, and radiation over the Southern Ocean near New Zealand.

A coordinated ground campaign, goSouth‑2, will deploy advanced remote‑sensing gear near Invercargill from September 2025 to March 2027. The goal is to watch clouds evolve in this pristine environment.

Life at the ocean’s surface shapes cloud brightness, revealing deep links between biology and the atmosphere.

The new evidence that marine polysaccharides help seed ice over huge swaths of the Southern Ocean is a vivid reminder: what grows in the water below can change the sky above – and, through clouds, influence Earth’s climate itself.

The study was presented at the EGU General Assembly 2025 in Vienna, Austria. An abstract of the article can be found here.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–