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Polar Bears Increasingly Thrive in the World’s Hottest Regions: A Study on Weight Gains

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Polar bears in Svalbard

Researchers Monitor Polar Bears’ Body Condition in Svalbard

John Earls, Norsk Arctic Institute

In the Svalbard archipelago of Norway, a region known for its climatic extremes, polar bears are surprisingly gaining weight despite the alarming reduction of sea ice. However, scientists warn this trend may not be sustainable.

The northern Barents Sea, located between Svalbard and Russia’s Novaya Zemlya, is warming disproportionately—seven times faster than the global average. Over the past two decades, sea ice around Svalbard has diminished, disappearing two months earlier each year. Currently, polar bears must swim over 200 kilometers between their hunting grounds and birthing caves.

<p>Despite this challenging environment, the overall size and weight of Svalbard’s polar bears has increased since 2000, presenting a puzzling contradiction. <a href="https://www.researchgate.net/profile/Jon-Aars-2">Jon Aars</a>, who led the research at the Norwegian Polar Institute, claims it's positive news for Svalbard. However, he cautions that areas most affected by climate change show severe decline in polar bear populations.</p>

<p>This widely dispersed solitary predator counts among its many challenges the difficulty of accurate population estimates. The numbers <a href="https://www.iucn-pbsg.org/wp-content/uploads/2024/11/PBSG-Status-Criteria-and-Report_Final_2024Oct7.pdf">are declining</a> in some regions while stable or even increasing in parts of Alaska, Canada, and Greenland; for nine populations, data remains insufficient.</p>

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<p>Estimations suggest the Barents Sea bear population ranges from 1,900 to 3,600 individuals, and appears stable or potentially increasing. From 1995 onward, researchers used tranquilizers via helicopter to study 770 bears, measuring their body length and thorax circumference to approximate weight.</p>
<p>Analysis of trends demonstrated a decline in body condition until 2000, followed by a gradual increase leading up to the last assessments in 2019.</p>

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                 data-caption="Polar bears depend on sea ice for many aspects of their lives" 
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                <p class="ArticleImageCaption__Title">Crucial Role of Sea Ice in Polar Bear Survival</p>
                <p class="ArticleImageCaption__Credit">Trine Lise Sviggum Helgerud, Norsk Arctic Institute</p>
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<p>In spring, the birth of seal pups on sea ice provides a vital food source for polar bears, allowing them to build fat reserves for the warmer months. Researchers like Earls speculate that diminishing ice may actually assist bears in hunting seals more easily.</p>
<p>With the retreating ice, bears are adapting by exploring new food sources. The approximately 250 bears remaining on Svalbard may increasingly hunt bearded and harbor seals along the coast, while thriving walrus populations might offer additional sustenance.</p>
<p>These adaptable "local bears" are now raiding nesting colonies for bird eggs and chasing reindeer, showcasing a remarkable resilience. According to researchers, such flexibility may be delaying their extinction, says <a href="https://www.researchgate.net/profile/Jouke-Prop">Jouke Prop</a> of the University of Groningen.</p>
<p>"This is a desperate tribe. They're doing unique things," he notes. "While this adaptability may not apply universally, it could suffice for a while in Svalbard."</p>
<p>Although polar bears have not yet reached Svalbard's ecological limits, thanks to the prohibition of hunting since 1973, warming temperatures threaten to disrupt the delicate food chain that begins with algae on sea ice, according to Prop.</p>
<p>"Should the sea ice vanish, sustaining a significant number of polar bears will become incredibly challenging," he warns.</p>
<p>"There exists a threshold beyond which continuous sea ice loss will negatively impact polar bears in Svalbard," Aars adds.</p>

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            <h3 class="SpecialArticleUnit__Heading">Uncover the Beauty of Svalbard and Tromsø</h3>
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                <p>Embark on an adventurous journey to Norway's Arctic region. Discover the scientific marvels behind the Northern Lights, the unique Arctic ecosystem, and how humans adapt to the challenges of the Far North.</p>
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    <p class="ArticleTopics__Heading">Topics:</p>
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Source: www.newscientist.com

Unlocking the Secrets of Jupiter and Saturn: How Polar Cyclones Expose Hidden Interiors

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A groundbreaking study by planetary scientists at the Massachusetts Institute of Technology (MIT) reveals how the significant differences in polar vortex patterns between Jupiter and Saturn are influenced by the unique properties of their deep interiors. These findings offer valuable insights into the structure of these gas giants.

This composite image, captured by the JIRAM instrument aboard NASA’s Juno satellite, depicts a central low-pressure system at Jupiter’s north pole along with eight surrounding low-pressure systems. The colors in this image represent radiant heat, revealing temperature variations in their cloud layers. Image credit: NASA / JPL-Caltech / SwRI / ASI / INAF / JIRAM.

“Our study shows that the internal properties, including the softness of the vortex base, influence the fluid patterns observed at the surface,” explained Dr. Wang-Ying Kang from MIT.

The research was inspired by stunning images of Jupiter and Saturn obtained from NASA’s Juno and Cassini missions.

Since 2016, Juno has been orbiting Jupiter and revealing astonishing details about its north pole and intricate spiral formations.

The data suggest that each vortex on Jupiter is immense, measuring around 5,000 km (3,000 miles) in diameter.

Meanwhile, Cassini documented Saturn’s iconic polar vortex, which spans a singular hexagonal shape approximately 29,000 km (18,000 miles) wide, before its controlled descent into Saturn’s atmosphere in 2017.

“Despite their similarities in size and primary composition of hydrogen and helium, deciphering the differences in polar vortices between Jupiter and Saturn has been challenging,” noted MIT graduate student Jial Shi.

Researchers aimed to uncover the physical mechanisms behind the formation of either a single vortex or multiple vortices on these distant planets.

To achieve this, they employed a two-dimensional model of surface fluid dynamics.

While polar vortices are inherently three-dimensional, the fast rotation of Jupiter and Saturn leads to uniform motion along their rotational axes, allowing the team to effectively analyze vortex evolution in two dimensions.

“In rapidly rotating systems, fluid motion tends to be uniform along the axis,” Dr. Kang added. “This insight allowed us to convert a 3D challenge into a 2D problem, significantly speeding up simulations and reducing costs.”

With this in mind, researchers created a two-dimensional model of vortex behavior in gas giants, adapting equations that describe the evolution of swirling fluids over time.

“This equation is commonly used in various situations, including modeling cyclones on Earth,” Dr. Kang stated. “We tailored it for the polar regions of Jupiter and Saturn.”

Scientists applied the two-dimensional model to simulate fluid dynamics on gas giants in various scenarios, adjusting parameters such as planetary size, rotational speed, internal heating, and the characteristics of the fluid.

They introduced random “noise” to simulate initial chaotic fluid flow on the planets’ surfaces.

By analyzing how this fluid evolved over time across different scenarios, the researchers found that some conditions led to the formation of a single large polar vortex, akin to Saturn’s structure, while others resulted in multiple smaller vortices, similar to those on Jupiter.

Through careful examination of the parameters affecting each scenario, the study identified a unifying mechanism: the softness of the vortex base constrains the size that vortices can attain.

The softer and lighter the gas at the bottom of the vortex, the smaller the resulting vortex, enabling multiple smaller vortices to exist at Jupiter’s poles. Conversely, a denser and harder base permits the growth of sizable vortices, manifesting as a singular entity like Saturn.

If this mechanism holds for both gas giants, it could suggest that Jupiter has a softer internal composition, while Saturn may contain denser materials.

“The fluid patterns we observe on the surface of Jupiter and Saturn may provide insights into their interior compositions,” Shi remarked.

“This is crucial because Saturn’s interior likely harbors richer metals and more condensable materials, leading to stronger stratification than that found in Jupiter,” Shi added. “This will enhance our understanding of gas giant planets.”

The team’s findings will be published in the Proceedings of the National Academy of Sciences.

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Gial Sea & One In Can. 2026. Polar vortex dynamics of gas giant planets: Insights from 2D energy cascades. PNAS in press.

Source: www.sci.news

Polar Bears Are Adapting Their Genetics to Thrive in a Warming Climate

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As climate change continues to undermine the icy habitats crucial for polar bear survival, new studies indicate that these bears are swiftly altering their genetic makeup to adapt.

This species is being compelled to cope with the increasingly harsh conditions of a warming Arctic, marking what scientists believe to be the first documented instance of rising temperatures prompting genetic adaptations in a mammal.

Research conducted by the University of East Anglia in the UK revealed findings: published in Friday’s issue of the journal Mobile DNA, which offers a rare glimmer of hope for these animals.

“Polar bears are sadly projected to face extinction this century, with two-thirds of their population potentially gone by 2050,” Alice Godden, the study’s lead author, shared with NBC News.

“We believe our findings genuinely provide a flicker of hope: a chance to reduce carbon emissions, mitigate climate change, and allow bears more time to adapt to significant changes in their habitats.”

Building on previous research from the University of Washington, Godden’s team studied blood samples from polar bears in northeastern and southeastern Greenland. In the comparatively warmer southern region, genes associated with heat stress, aging, and metabolism showed different behavior compared to those in the north.

“Essentially, this indicates that various groups of bears are modifying different segments of their DNA at varying rates, with this activity seemingly linked to their specific environmental and climatic contexts,” Godden mentioned in a university press release.

He remarked that this is the first indication that a distinct population of a species has been driven to “rewrite its own DNA,” suggesting this process is a “desperate survival mechanism” against disappearing sea ice.

The Arctic Ocean has consistently recorded unusually high temperatures in recent years, as reported by the National Oceanic and Atmospheric Administration (NOAA). Monitoring data suggests.

Researchers assert that rising ocean temperatures are diminishing the vital sea ice foundation that bears rely on for hunting seals, leading to isolation and food shortages.

Godden explained to NBC News that the genetic changes emerged as the bears’ digestive systems adapted to food scarcity, including a lack of prey, plant life, and low-fat diets.

“Access to food poses a critical challenge for these bears everywhere, particularly in the South,” she notes. “This may indicate that their physical structure and composition are also evolving in response to warmer surroundings.”

The lead researcher stated that her team targeted the southern bear group as the region’s warmer climate provides insights into what other bear populations may experience later this century if current climate trends persist.

The International Union for Conservation of Nature estimates around 26,000 polar bears currently exist globally. Known scientifically as Ursus maritimus, or “sea bear,” these animals are classified as Vulnerable on the IUCN Red List of Threatened Species, believed to be at “high risk of extinction in the wild.”

The research “doesn’t imply that polar bears are at a reduced risk of extinction,” Godden stated. However, she added this finding “could provide a genetic framework for how polar bears may swiftly adapt to climate change.”

Godden further urged, “We all need to take action to reduce our carbon footprint and create opportunities to protect and expand this incredible and vital species.”

Source: www.nbcnews.com

Growler Bears and Pizzly Bears: Insights from the Hybrid Family Drama of Polar and Grizzly Bears

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Arctic Grolar Bear

Stephen J. Kazlowski / Alamy

<p>Meet our central figure: a female polar bear. Driven southward by retreating Arctic ice, she journeyed deep into Canada's Northwest Territories. There, she encountered a pair of striking grizzly bears, and fell in love with both. From these unions, she gave birth to three daughters known as "growler bears" and a son, marking the inception of an extraordinary lineage echoing Shakespearean drama.</p>

<p>The next chapter took an unexpected turn. When one of her daughters matured, she mated with her biological father and another grizzly, her stepfather, resulting in a litter of four—siblings, children, and cousins all at once.</p>

<p>In 2006, a hunter in the Canadian Arctic produced a hybrid specimen with both polar and grizzly traits. Later genetic evaluation confirmed this was a growler, part of this emerging hybrid family. A decade later, scientists were intrigued to observe unusual behaviors among these creatures. Typically, hybrids are not fertile, yet these were. Researchers began to ponder whether this heralded a new apex predator for the Arctic. Could these hybrids exemplify resilience in the face of climate change, or signal impending ecological crises? Current studies promise further insights.</p>

<p>As global temperatures increase, the Arctic warms four times quicker than the rest of the globe, pushing polar bears (<em>Ursus maritimus</em>) south in search of sustenance. Their primary diet of fatty seals hinges on sea ice, which is disappearing rapidly, forcing them inland. They frequently encounter their brown bear relatives, the grizzly bear (<em>Ursus arctos horribilis</em>), which is edging northward. Warmer Arctic conditions enhance hunting and breeding opportunities, boosting hybrid occurrences, including growlers and "pizzly bears" (polar bear fathers and grizzly mothers). Some researchers express concern that polar genes may infiltrate grizzly populations, jeopardizing polar bear survival.</p>

<p>Yet, the discovery of the Grolar lineage hints at a more optimistic scenario: polar bears might be adapting to a rapidly changing environment. Recorded growlers exhibit traits of gray-brown polar bears, with slightly larger limbs and skulls reminiscent of grizzlies. These hybrids might exploit a broader diet on land, potentially allowing them to forage without relying on diminishing sea ice. Larissa DeSantis, a paleontologist at Vanderbilt University, notes that these adaptations could be a bittersweet necessity amid rising temperatures, as discussed in a <a href="https://www.livescience.com/pizzly-bear-hybrids-created-by-climate-crisis.html">2021 interview.</a></p>

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<h2>One Happy Family</h2>

<p>However, <a href="https://link.springer.com/article/10.1007/s12686-024-01359-1">extensive genomic research</a> presented in a recent book reveals alternative insights. In a study led by <a href="https://www.macewan.ca/academics/academic-departments/biological-sciences/our-people/profile/?profileid=millerj253">Joshua Miller</a> at MacEwan University, researchers uncovered that genetic sequences of 371 polar bears, 440 grizzlies, and the Grolar clan showed no other hybrids in nature apart from the known Grolars. The rarity of this mating pattern has led experts to conclude that hybrids may lack the essential skills required for survival in either parent's ecosystem. Recent studies corroborate that hybrids may be unfit for Arctic life, lacking polar bears' specialized "non-slip" foot structure and not fully inheriting grizzlies’ powerful forelimbs and shoulders. Essentially, Growlers and Pizzlies are suboptimal versions of both bears rather than well-adapted hybrids.</p>

<p><figure class="ArticleImage"><div class="Image__Wrapper"><img class="Image" alt="Two pizzly bears in a stream at the zoo" width="1350" height="900" src="https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg" srcset="https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=300 300w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=400 400w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=500 500w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=600 600w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=700 700w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=800 800w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=837 837w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=900 900w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=1003 1003w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=1100 1100w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=1200 1200w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=1300 1300w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=1400 1400w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=1500 1500w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=1600 1600w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=1674 1674w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=1700 1700w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=1800 1800w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=1900 1900w, https://images.newscientist.com/wp-content/uploads/2025/11/05152243/SEI_273018522.jpg?width=2006 2006w" sizes="(min-width: 1288px) 837px, (min-width: 1024px) calc(57.5vw + 55px), (min-width: 415px) calc(100vw - 40px), calc(70vw + 74px)" loading="lazy" data-image-context="Article" data-image-id="2503195" data-caption="Pizzly bears in a German zoo, born from a polar bear father and grizzly mother in the same enclosure." data-credit="Molly Merrow"/></div><figcaption class="ArticleImageCaption" wp_automatic_readability="27"><div class="ArticleImageCaption__CaptionWrapper" wp_automatic_readability="34"><p class="ArticleImageCaption__Title">Pizzly Bear Born from a Polar Bear Father and Grizzly Mother</p><p class="ArticleImageCaption__Credit">Molly Merrow</p></div></figcaption></figure></p>

<p>Short-term, such hybrids may remain uncommon, with new species unlikely. However, what about the long-term evolutionary prospects for polar bears? Insights from the past might illuminate the future. The habitats of polar and brown bears once coexisted during the Pleistocene epoch, defined by recurring glaciation over the last 2.6 million years. Researchers at the University of California, Santa Cruz discovered that brown bears currently inhabit three Alaskan islands. <a href="https://pubmed.ncbi.nlm.nih.gov/23516372/">During that time, gradual male brown bear mating with local polar bear populations resulted in hybridization.</a> If this pattern recurs, the polar bear species could face extinction, leaving only grizzly bears.</p>

<p>However, the Pleistocene was characterized by gradual environmental changes and slow adaptation. Today’s climate change, driven by human activity, is happening at an unprecedented pace, potentially leading us down an alternate path. “The far more significant threat to polar bears today is the loss of ice habitat due to climate change, occurring much more swiftly than any concerns related to hybridization,” states Fiona Galbraith, a geneticist and climate change consultant currently leading a natural habitat expedition into the Canadian Arctic.</p>

<p><figure class="ArticleImage"><div class="Image__Wrapper"><img class="Image" alt="Icebergs are melting at the North Pole" width="1350" height="900" src="https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg" srcset="https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=300 300w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=400 400w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=500 500w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=600 600w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=700 700w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=800 800w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=837 837w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=900 900w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=1003 1003w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=1100 1100w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=1200 1200w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=1300 1300w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=1400 1400w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=1500 1500w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=1600 1600w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=1674 1674w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=1700 1700w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=1800 1800w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=1900 1900w, https://images.newscientist.com/wp-content/uploads/2025/11/05152237/SEI_273019037.jpg?width=2006 2006w" sizes="(min-width: 1288px) 837px, (min-width: 1024px) calc(57.5vw + 55px), (min-width: 415px) calc(100vw - 40px), calc(70vw + 74px)" loading="lazy" data-image-context="Article" data-image-id="2503193" data-caption="The Arctic is warming four times faster than the rest of the planet" data-credit="Adisha Pramod/Alamy"/></div><figcaption class="ArticleImageCaption" wp_automatic_readability="26"><div class="ArticleImageCaption__CaptionWrapper" wp_automatic_readability="32"><p class="ArticleImageCaption__Title">The Arctic is Warming Four Times Faster Than the Rest of the Planet</p><p class="ArticleImageCaption__Credit">Adisha Pramod / Alamy</p></div></figcaption></figure></p>

<p>In conclusion, while the Grolar dynasty is fascinating, it serves as a harbinger of ecological distress on Earth. Similar <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC10674025/">climate-induced mating</a> has been documented elsewhere, including a **bobcat-lynx hybrid** in North America and the emergence of the **coywolf**, resulting from interbreeding between coyotes and eastern wolves. Like Arctic bears, these hybrids are born from habitat disruption caused by rapidly changing environments. Their ability to adapt is situation-dependent; many hybrids struggle to thrive in new areas, often leading to biodiversity loss and eventual ecosystem collapse. "When both species fulfil similar roles in their ecosystems, increased contact and interbreeding can occur without significantly affecting ecological functions," shares <a href="https://polarbearsinternational.org/what-we-do/our-team/">John Whiteman</a> from Polar Bears International. Neglecting this could lead to dire consequences. For instance, while grizzly bears frequently leave carrion for scavengers, polar bears do not, posing hazards to food webs and disease dynamics.</p>

<p>Reflecting on our initial question about the Grolar dynasty as the next chapter in polar bear evolution, the resounding answer is a grim "no." This phenomenon showcases not adaptation but the tragic decline of a species amid drastic environmental fluctuations. However, this festive season, let’s contemplate the potential for a different outcome, where polar bear tracks continue to mark the Northern landscapes for winters yet to come. It hinges on our actions.</p>

<section class="ArticleTopics" data-component-name="article-topics"><p class="ArticleTopics__Heading">Topic:</p></section>

Source: www.newscientist.com

Century-Old Mercury Poisoning Abandons Polar Bears

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Mercury pollution resulting from early coal burning and gold mining continues to affect Arctic wildlife over a century later. New research published in Natural Communication reveals these enduring effects.

Despite worldwide efforts to limit emissions, mercury levels in apex predators like Arctic and toothed whales remain alarmingly high. Researchers attribute this persistence to legacy contamination that travels through ocean currents to the Arctic region.

A research team has analyzed more than 700 samples collected across Greenland over the last 40 years, ranging from animal tissues to ground peat. By evaluating the chemical “fingerprints” of mercury isotopes, they discovered that mercury concentrations have not declined and, in some cases, remain elevated in Arctic ecosystems.

“This provides insight into why we haven’t seen a decrease in Arctic mercury levels,” stated Professor Runeatz, a co-author of the study. “Mercury transport from significant sources like China to Greenland can take up to 150 years.”

Mercury released into the atmosphere through human activities can circulate the globe for approximately a year before settling. However, once it enters the ocean, it may persist for centuries, gradually moving northward through deep, cold currents.

For instance, Central West Greenland is influenced by Atlantic influx via the North Atlantic Arminger current, while other areas receive mercury-laden water from the Arctic current.

Beluga-like tooth whales today have mercury concentrations up to 30 times greater than before the Industrial Revolution – Getty

Currently, mercury concentrations in polar bears and toothed whales are 20-30 times higher than pre-industrial levels.

“We don’t have evidence of actual killings of top predators,” Dietz commented. According to an email from BBC Science Focus, “However, the loads in toothed whales and polar bears, along with Inuit populations in highly exposed areas, are significant enough to indicate neurological effects.”

As a potent neurotoxin, mercury can harm immune and reproductive health. Naturally occurring elements are extremely dangerous, as noted by the World Health Organization, which lists it as “one of the top 10 chemicals of major public health concern.”

The findings carry significant implications for the United Nations Mamata Treaty, a global initiative aimed at decreasing mercury pollution. While reduction of emissions is crucial, the study implies that the Arctic may require generations to see recovery.

The research team will continue to explore mercury’s impact on vulnerable Arctic ecosystems. Dietz emphasizes that modeling how long mercury takes to travel from major emitters like China to various Arctic regions could be essential for understanding long-term threats.

Read more:

About our experts

Rune Deets is a professor at the Faculty of Ecoscience at Aarhus University. His research has been published in peer-reviewed journals including Environmental Research, Molecular Ecology, and Ecology and Evolution.

Source: www.sciencefocus.com

Fossils from 73 Million Years Ago Reveal the Earliest Evidence of Bird Nesting in Polar Regions

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Polar ecosystems are bolstered and enriched by birds that nest there seasonally, serving as keystone members of these ecosystems. Despite the significant ecological role of polar birds, the origins of high-center nests remain unclear due to limited fossil evidence. A recent study conducted by paleontologists explored an extensive collection of bird fossils from the late Cretaceous Purine Cream Formation in Alaska.

Illustration of Cretaceous birds alongside other dinosaurs from the same period. Image credit: Gabriel Ugueto.

“Birds have existed for 150 million years,” stated Lauren Wilson, a doctoral candidate at Princeton University.

“For a significant portion of that time, they constructed nests in the Arctic.”

In their research, Wilson and colleagues studied the bones and teeth of fossilized birds from the Alaska Prune Creek Formation, dating back 73 million years.

They identified various bird types, including land birds, seagull-like birds, and diving birds that bear similarities to some modern ducks and geese, all of which were nesting in the Arctic while dinosaurs roamed the same territory.

Before this research, the earliest known evidence of breeding birds in the Arctic or Antarctic was approximately 47 million years ago, following the asteroid impact that wiped out 75% of Earth’s species.

“This will extend the timeline by 25-30 million years for records of birds breeding in the polar regions,” remarked Dr. Pat Druckenmiller, director of the University of Alaska Museum.

“The Arctic is recognized as a modern nursery for birds.”

“Finding bird bones from the Cretaceous period is exceptionally rare,” Wilson noted.

“Discovering baby bird bones is almost unheard of, making these fossils particularly significant.”

“We conducted extensive mapping of Alaska for fossil birds—it wasn’t on anyone’s radar,” added Dr. Druckenmiller.

“Now, we are one of the premier locations in the country for bird fossils from the dinosaur age.”

“Given the richness of this information, these small bones and teeth offer exceptional insights into the fauna from that era.”

It remains uncertain whether these newly discovered specimens are the earliest recognized members of Neornithes, a category that encompasses all modern birds.

Some of the newly unearthed bones exhibit skeletal characteristics exclusive to this group. Additionally, like contemporary birds, some did not possess true teeth.

“If they belong to a modern bird lineage, they would represent the oldest fossils ever found,” explained Dr. Druckenmiller.

“Currently, the oldest such fossils are about 69 million years old.”

“However, establishing that requires the discovery of a partial or complete skeleton.”

Survey results I will be featured this week in the journal Science.

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Lauren N. Wilson et al. 2025. Evidence of bird nesting in the Arctic dates back to the Cretaceous period. Science 388 (6750): 974-978; doi: 10.1126/science.adt5189

Source: www.sci.news

Astronomers Uncover Polar Ejection Stripping Systems Surrounding Brown Dwarf Pairs

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The recently identified planet orbits a binary system comprising two equal brown dwarf stars positioned at a 90-degree angle from 2mass J15104786-2818174 (hereafter referred to as 2M1510).

This diagram illustrates exoplanets orbiting two brown dwarfs. Image credit: ESO/M. Kornmesser.

Cardiovascular planets represent the realm of diabetes found within a binary star system.

These planets generally have orbits aligned with the planes in which their host stars revolve around one another.

Previously, there were indications that planets might exist in vertical or polar orbits. Theoretically, these orbits were stable, and disc formations observed suggested potential planets around polar orbits of stars.

However, astronomers have now obtained clear evidence of the existence of these polar planets.

“We are thrilled to have played a role in finding robust evidence for this configuration,” stated PhD candidate Thomas Beycroft from the University of Birmingham.

The newly discovered exoplanet, 2M1510B, orbits a unique pair of young brown dwarfs.

These brown dwarfs undergo mutual solar eclipses as viewed from Earth, a characteristic that qualifies them within what astronomers refer to as a binary system.

This configuration is exceptionally rare, marking only the second identified pair of brown dwarfs and the first solar system discovered at a right angle relative to the orbit of its two host stars.

Artist’s impression of the unusual trajectory of 2M1510B around the brown dwarf. Image credit: ESO/L. Calsada.

“The planet revolving around the binary brown dwarfs in a polar orbit is remarkably thrilling,” commented Amalie Triaudo, a professor at the University of Birmingham.

Astronomers discovered 2M1510B by refining the trajectories and physical characteristics of the two brown dwarfs using UV and Visual Echelle Spectroscopy (UVES) at ESO’s Very Large Telescope.

The researchers observed strange forces acting on the trajectory of the brown dwarf, leading to speculation about a unique formation with an unusual orbital angle.

“After considering all plausible scenarios, the only explanation consistent with our data is that the planet within this binary is in polar orbit,” Beycroft noted.

“This discovery was fortuitous, as our observations weren’t initially aimed at studying the composition or orbit of such a planet, making it an exciting surprise,” Professor Triaud explained.

“Overall, I believe this not only showcases our astronomers’ capabilities but also illuminates the possibilities within the intriguing universe we inhabit.”

This image depicts the triple system 2M1510. Image credits: Centre Donna Astromyk destrasbourg/Sinbad/Panstars.

This discovery was made possible due to innovative data analysis developed by Dr. Larita Sylum of Cambridge University.

“We can derive their physical and orbital parameters from the variation in speed between the two brown dwarfs, although these measurements were previously uncertain,” Dr. Sairam remarked.

“This improvement has revealed that the interactions between the two brown dwarfs are intricately influenced.”

Study published in the journal Advances in Science.

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Thomas A. Baicroft et al. 2025. Evidence of polar drainage bulges orbiting a pair of brown dwarfs. Advances in Science 11 (16); doi:10.1126/sciadv.adu0627

Source: www.sci.news

Rare footage of a mother polar bear and her cubs emerging from their den shed light on their elusive behavior

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It's published today International Polar Bear Daynew research will answer questions by showing the first combination of satellite tracking colors and remote camera traps Polar bear (Ursus Maritimus)) Denning is notoriously difficult to study as polar bear moms create dens under the snow in remote areas.

Shooter et al. It reveals the first detailed view of polar bear cults coming out of their burrows. Image credits: Jon Aars/Norwegian Polar Institute.

Turnip survival supports species survival, and denning is the most vulnerable period of life. Less than 50% of Cubs can become adults.

As industry expands in the Arctic, this study highlights the importance of uninterrupted Denning regions to protect polar bear populations.

“Polar bear mothers have increased difficulty replicating due to climate-based changes and could face additional challenges associated with expanding human footprints in the Arctic,” said Dr. Louise Archer, a researcher at the University of Toronto Scarborough University.

“We are excited to introduce new tools to monitor bears during this vulnerable period and gain insight into action across the Arctic.

“Every den we monitor has its own story, and every data point adds to this critical understanding of time and supports a more effective conservation strategy.”

In their study, the authors monitored the behavior of the polar bears in Den Emans held in Svalbad, Norway.

Female polar bears were equipped with GPS satellite collars recording their location, temperature and activity.

Researchers used these collar data to find burrows and traveled through the mountains of Svalbad to deploy time-lapse camera traps at 13 densites over six years.

They found that camera traps provide fine-scale insight into the behavior of the maternal Den, and that satellite collars are accurate and useful for monitoring bears in more remote locations for longer periods of time.

https://www.youtube.com/watch?v=fcf0fyq_e_i

The family appeared in Svalbarbad around March 9th and appeared to abandon the burrow earlier than previously recorded in this group, and further monitoring was needed to establish whether this was a continuing trend.

Changing the timing of denning can put a risk to the cubs' survival as they will less time to develop before they can proceed further towards the sea ice.

In some cases, the bears appeared from the burrow in less than a minute before returning inside, while other appearances lasted for several hours.

In terms of departing den forever, camera footage showed that polar bears remained near the burrow to stay on average for 12 days.

However, this ranged between 2-31 days and was very different among polar bear families.

Some moms switched dens – they were observed leaving their original dens and moving their families to new dens.

Cubs are heavily dependent on their mothers and rarely venture out in their dens alone. The Cubs were only seen in 5% without mothers. In Svalbad, they rely on their mothers for up to 2.5 years.

“This study gives us a total glimpse into one of the most vulnerable and important periods of polar bear life and provides insights that will help guide our collective conservation efforts.”

“Combining innovative technology and long-term research gives us a deeper understanding of the challenges faced by polar bear moms and cubs in the rapidly changing Arctic.”

“Conserving Denning's habitat is essential for population health, and this study provides invaluable insights that can help guide conservation management.”

“There were few studies that included observational data at polar bear burrow sites, and therefore this study contributes significantly to our knowledge of denning ecology,” said Dr. John Arles, a senior researcher at the Norwegian Polar Institute.

Furthermore, data from the satellite radio collar was available to all mothers, and observational data allowed us to communicate how recorded activity and temperature changes corresponded to behavior. ”

study It will be displayed in Journal of Wildlife Management.

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Louise C. Archer et al. Monitoring the phenology and behavior of polar bears during the emergence of den using cameras and satellite telemetry. Journal of Wildlife ManagementPublished online on February 26th, 2025. doi: 10.1002/jwmg.22725

Source: www.sci.news

Mars’ polar regions covered in white due to carbon dioxide ice

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Planetary scientists using ESA's Mars Express spacecraft's high-resolution stereo camera have captured stunning images of Earth's mysterious landscapes. Australe Scopri Region in the southern hemisphere of the red planet.

Frozen landscape of the Australe Skopli region on Mars' south pole. Image credit: ESA / DLR / FU Berlin.

“Here, a layer of carbon dioxide ice and dust envelops the site, turning Mars white,” ESA researchers said in a statement.

“The contrasting light and dark layers are especially striking on the exposed surfaces of hills and valleys.”

“They track the seasonal polar layered deposits characteristic of the region, which form when layers of ice freeze and trap varying amounts of dust within them. It is something that will be done.”

“It's probably better to take a sled ride, but either way, dress warmly, because it's -125 degrees Celsius (-193 Fahrenheit) outside so it's cold,” they added.

“Skiers and sledders on Mars will have to slalom around potentially hundreds of dust jets.”

“That's because ski season is almost over and it's starting to look like spring, or even summer. This image was taken on June 16, 2022, near the Antarctic summer solstice.”

If you zoom in on the image above, you can see numerous dark spots where the ice has already sublimated. This is a sure sign that the sun's warming rays have been hitting the area for some time.

“When sunlight hits the translucent upper layer of carbon dioxide ice, it warms the underlying surface,” the scientists explained.

“The ice at the bottom of the layer begins to sublimate, forming pockets of trapped gas.”

“As the pressure increases, the overlying ice suddenly cracks, causing gas to burst out from the surface.”

“These gas fountains carry black dust from below, which falls to the surface in a fan-shaped pattern depending on the prevailing wind direction.”

“Fan lengths range from tens of meters to hundreds of meters.”

“If you look more closely, it often appears that the fans follow the boundaries between polar layered deposits.”

“Perhaps these boundaries represent zones of weakness, from which escaping dust-laden jets can more easily break through the ice layer.”

“We may have missed the chance to create 'Frosty the Snowman,' but it's still a wonderful time of year on Mars.”

Source: www.sci.news

Astronomers witness Jupiter’s ephemeral dark polar ellipse in ultraviolet light

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Earth-sized ovals at Jupiter's north and south poles, visible only at ultraviolet (UV) wavelengths, appear and disappear at seemingly random intervals, according to a study led by astronomers at the University of California, Berkeley.

False-color ultraviolet image of the entire planet showing a hood or cap of hydrocarbon fog covering the south pole. The edge of the arctic hood is visible at the top. Image credit: Troy Tsubota and Michael Wong, University of California, Berkeley.

Jupiter's dark ultraviolet ellipses are mostly located directly beneath bright auroral bands at each pole, similar to Earth's northern and southern lights.

This spot absorbs more ultraviolet light than the surrounding area, so it appears darker in images from the NASA/ESA Hubble Space Telescope.

In annual images of the planet taken by Hubble between 2015 and 2022, dark ultraviolet ellipses appear 75% of the time at the south pole, but only in one in eight images taken at the north pole. A dark oval will appear.

The dark ultraviolet ellipses suggest that unusual processes are occurring in Jupiter's strong magnetic field. This magnetic field propagates all the way to the poles and deep into the atmosphere, much deeper than the magnetic processes that produce auroras on Earth.

The dark ultraviolet ellipse was first detected in the 1990s by Hubble at the North and South poles, and later also at the North Pole by NASA's Cassini spacecraft, which flew close to Jupiter in 2000, but received little attention.

In a new analysis of Hubble images, University of California, Berkeley undergraduate student Troy Tsubota and his colleagues found that the oval shape is a common feature of Antarctica. They counted eight Southern Ultraviolet Dark Ovals (SUDOs) between 1994 and 2022.

In all 25 Hubble Earth maps showing Jupiter's north pole, only two northern ultraviolet dark ellipses (NUDOs) were found.

Most of the Hubble images were taken as part of the Outer Planet Atmospheres Legacy (OPAL).

“In the first two months, we realized that these OPAL images were kind of a gold mine. We quickly built this analysis pipeline and asked what we could get by sending all the images. We were able to confirm that,” says Tsubota.

“That's when we realized we could actually do good science and real data analysis and have conversations with our collaborators about why these things appear.”

The authors also aimed to determine the cause of these areas of dense fog.

They theorized that the dark ellipse was likely being stirred up from above by a vortex created when the planet's magnetic field lines rub at two very far apart locations. One is the friction in the ionosphere and the Earth's sheet, the rotational motion of which has previously been detected using ground-based telescopes. Hot ionized plasma around the planet emitted by the volcanic moon Io.

The vortex rotates fastest within the ionosphere and gradually weakens as it reaches deeper layers.

Like a tornado landing on dusty ground, the deepest parts of the vortex stir up the hazy atmosphere, creating the dense patches observed by astronomers.

It is unclear whether the mixing will dredge more haze from below or create additional haze.

Based on their observations, researchers believe that the oval shape may form over about a month and disappear within a few weeks.

Astronomer Dr Shih Zhang said: “The dark elliptical haze is 50 times thicker than typical concentrations. This is because this haze is due to the dynamics of the vortex, rather than a chemical reaction caused by high-energy particles from the upper atmosphere. This suggests that it is likely to have been formed by At the University of California, Santa Cruz.

“Our observations show that the timing and location of these high-energy particles do not correlate with the appearance of the dark ellipses.”

This discovery, which the OPAL project was designed to discover, will reveal how the atmospheric dynamics of the solar system's giant planets differ from what we know on Earth. .

“Studying the connections between different atmospheric layers is extremely important for all planets, whether exoplanets, Jupiter, or Earth,” said Dr. Michael Wong, an astronomer at the University of California, Berkeley.

“We see evidence of processes connecting everything throughout the Jovian system, from internal dynamos to satellites, plasma torii, ionospheres, and stratospheric haze.”

“Finding these examples helps us understand the entire planet.”

of study Published in a magazine natural astronomy.

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TK Tsubota others. Jupiter's ultraviolet to dark polar ellipse shows the connection between the magnetosphere and atmosphere. Nat Astronpublished online on November 26, 2024. doi: 10.1038/s41550-024-02419-0

This article is adapted from the original release by the University of California, Berkeley.

Source: www.sci.news

New Study Finds Polar Vortex Surrounding the Sun

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Polar vortices exist in the atmospheres of planets ranging from rocky Earth-like planets to gas giants like Jupiter and Saturn. However, currently not much is known about their presence and characteristics on the Sun due to the lack of direct observations in the polar regions. Unlike planetary atmospheres, the Sun’s underground layers are greatly influenced by the presence of magnetic fields. New research shows that the solar cycle’s magnetic fields provide the mechanism for the formation of polar vortices in the Sun.

On August 31, 2012, the corona, a long filament of solar material suspended in the Sun’s atmosphere, erupted into space at 4:36 p.m. EDT. CME traveled at more than 900 miles per second. Although it did not fly directly towards Earth, the single shot connected with Earth’s magnetic environment, or magnetosphere, and caused the aurora borealis to appear on the night of September 3rd. Image credit: NASA’s Goddard Space Flight Center.

“No one can say exactly what’s going on at the solar pole,” says Dr. Mausmi Dikpati, a senior scientist at the NSF National Center for Atmospheric Research’s High Altitude Observatory.

“But this new study gives us an interesting look at what we might expect to find when we are able to observe the solar pole for the first time.”

It is not surprising that some kind of polar vortex may exist on the Sun.

These rotating geological formations develop in the fluid surrounding rotating bodies due to the Coriolis force and are observed on most planets in the solar system.

On Earth, vortices rotate high in the atmosphere around both the north and south poles.

When these vortices are stable, frigid air is trapped at the poles, but when they weaken and become unstable, that cold air penetrates toward the equator, creating cold air in the midlatitudes. cause

NASA’s Juno mission has returned breathtaking images of Jupiter’s polar vortices, showing there are eight tightly packed vortices around the gas giant’s north pole and five around its south pole.

Saturn’s polar vortex, observed by NASA’s Cassini spacecraft, is hexagonal at the north pole and more circular at the south pole.

These differences provide scientists with clues to the composition and dynamics of each planet’s atmosphere.

Polar vortices have also been observed on Mars, Venus, Uranus, Neptune, and Saturn’s moon Titan, so the fact that the Sun (also a rotating body surrounded by fluid) has such a feature may be obvious in some ways. yeah.

However, the sun is fundamentally different from planets and satellites, which have atmospheres. The plasma surrounding the sun is magnetic.

How that magnetism affects the formation and evolution of the Sun’s polar vortex, or whether it forms at all, remains a mystery. This is because humans have never sent a probe into space that can observe the poles of the sun.

In fact, our observations of the Sun are limited to views of the Sun’s face when it points towards the Earth, which only provides hints about what’s happening at the poles.

Astronomers have never observed the sun’s poles, so the study authors turned to computer models to fill in the blanks about what the sun’s polar vortex looks like.

What they discovered is that the Sun does indeed likely have a unique polar vortex pattern that evolves as the solar cycle unfolds and depends on the strength of the particular cycle.

Simulations show that a tight ring of polar vortices forms at about 55 degrees latitude, which corresponds to Earth’s Arctic Circle, at the same time that a phenomenon called “polar plunge” begins.

At the maximum of each solar cycle, the magnetic field at the sun’s poles disappears and is replaced by a magnetic field of the opposite polarity.

This flip-flop is preceded by a “polar plunge” in which a magnetic field of opposite polarity begins to move toward the pole from about 55 degrees latitude.

After formation, the vortices move towards the poles within the constricting ring, releasing the vortices as the circle closes, until eventually only a pair of vortices directly adjacent to the poles remain, completely disappearing during solar maximum.

The number of vortices that form and their configuration as they move toward the poles changes with the strength of the solar cycle.

These simulations provide a missing piece to the puzzle of how the Sun’s magnetic field behaves near the poles and could help answer some fundamental questions about the Sun’s solar cycle.

For example, many scientists have traditionally used the strength of the magnetic field “pushing to the poles” as a proxy for how strong future solar cycles are likely to be.

However, the mechanism of how they are connected, if at all, is not clear.

The simulation also provides information that can be used to plan future missions to observe the Sun.

In other words, this result shows that some form of polar vortex is observable during all parts of the solar cycle except during solar maximum.

“You could launch a solar mission and arrive at the pole at exactly the wrong time,” says Scott McIntosh, also of the NSF National Center for Atmospheric Research’s High Altitude Observatory.

Solar Orbiter, a joint mission between NASA and ESA, may give researchers their first glimpse of the solar pole, but the first glimpse will be close to solar maximum.

Scientists say a mission aimed at observing the poles and providing researchers with multiple simultaneous views of the sun could help solve long-standing questions about the sun’s magnetic field.

Dr. McIntosh said, “Our conceptual boundaries are that we currently operate from only one perspective.”

“To make significant progress, we need the necessary observations to test our hypotheses and see if simulations like this are correct.”

of result will appear in Proceedings of the National Academy of Sciences.

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Mausumi Dikpati others. 2024. Magnetohydrodynamic mechanism of solar polar vortex formation. PNAS 121 (47): e2415157121;doi: 10.1073/pnas.2415157121

Source: www.sci.news

Footprints of a polar dinosaur discovered in Australia dating back 120 million years

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The newly discovered theropod and ornithopod dinosaur footprints date back to the Early Cretaceous period, more than 120 million years ago, when Australia was still connected to Antarctica.

Melissa Lawley and Anthony Martin examine dinosaur footprints. Image by Ruth Showalter.

Dinosaur footprints from the Early Cretaceous period have been discovered in the Wonthaggi Formation south of Melbourne, Australia.

These include 18 footprints of medium to large theropods (0.8-1.9 metres waist height) and four footprints of small ornithopod dinosaurs (40-48 centimetres waist height).

“These numerous footprints provide the best evidence yet that polar environments once supported large carnivores,” said Professor Anthony Martin of Emory University.

“Large theropods probably fed on prey such as smaller dinosaurs, fish and turtles.”

“The hip height of this theropod would have been roughly the same as the height of a tall modern human.”

“Rocky coastal strata in Victoria, Australia, mark the spot where the ancient supercontinent Gondwana began to break up about 100 million years ago, separating Australia from Antarctica.”

“The polar environment at that time was a rift valley with a network of rivers running through it.”

“Although the average annual temperature during the Cretaceous period was higher than today, ecosystems experienced freezing temperatures and months of darkness during polar winters.”

“The Wonthaggi Formation has produced one of the best assemblages of polar dinosaur fossils in the Southern Hemisphere, but most of these fossils are small fragments of bone and teeth.”

“These pieces may have been carried to the buried site by heavy spring rains.”

“However, the discovery of so many theropod footprints confirms that a wide variety of dinosaurs did in fact live and walk on the surface where the bones were found.”

“Dinosaur footprints are actually more common here than we previously thought.”

Theropod footprints in the Wonthaggi Formation range in length from 18 to 47 cm (7 to 18.5 in).

They have relatively thin toes and sharp claw tips.

Ornithopod tracks vary in size from 10 to 18 cm (4 to 7 in).

The range of footprint sizes suggests that they may represent a mixture of juvenile and adult ornithopods and theropods.

“This suggests that these dinosaurs may have been nesting and raising their young in polar environments,” Prof Martin said.

This discovery paper of Archealinga, Australian Journal of Palaeontology.

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Anthony J. Martin othersPolar dinosaur footprints from the Wonthaggi Formation (Lower Cretaceous), Victoria, Australia, and their palaeontological significance. Archealinga, Australian Journal of PalaeontologyPublished online September 8, 2024; doi: 10.1080/03115518.2024.2392498

Source: www.sci.news

Study finds that Jupiter’s polar lows are driven by processes reminiscent of those on Earth

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Planetary scientists first became aware of the connection between Earth and Jupiter in 2018, when they noticed striking similarities in images of Jupiter's giant cyclones and turbulent ocean currents. In 2022, they Analyzed High-resolution infrared image of a cyclone on Jupiter taken by NASA's Juno spacecraft. Analysis reveals that a type of convection similar to that seen on Earth helps sustain Jupiter's storms, which can be thousands of miles wide and last for years. The 2022 study focused directly on Jupiter's cyclones, but the authors also saw thin tendrils called filaments in the spaces between the vortices of gas. These filaments have analogues on Earth, and the authors used Juno's detailed images to study whether this similarity to Earth's oceanic and atmospheric processes is merely superficial.

This composite image, created from data collected by the JIRAM instrument on NASA's Juno spacecraft, shows a central cyclone at Jupiter's north pole and eight surrounding cyclones. JIRAM collects data in infrared, and the colors in this composite represent radiated heat. The yellow (thinnest) clouds have a brightness temperature of about -9 degrees Fahrenheit (-13 degrees Celsius), while the dark red (thickest) clouds have a brightness temperature of about -181 degrees Fahrenheit (83 degrees Celsius). Image credit: NASA / JPL-Caltech / SwRI / ASI / INAF / JIRAM.

Fronts are often featured in weather forecasts (for example, cold fronts and storm fronts) and apply to both gases and liquids.

A front is a boundary between masses of gas or liquid that have different densities due to differences in properties such as temperature.

In the ocean, fronts can also form due to differences in salinity, which, along with temperature, affects the density of seawater.

The main characteristic of a front is that its leading edge is characterized by strong vertical speed and can generate wind and currents.

To understand the role of the filaments clearly visible during Jupiter's cyclones in the Juno images, Dr. Leah Siegelman of the Scripps Institution of Oceanography and Dr. Patrice Klein of the California Institute of Technology examined a series of infrared images from Juno.

The series of images was taken 30 seconds apart of Jupiter's north polar region.

Because the images were taken in infrared, the team was able to calculate the temperature, finding that brighter areas were warmer and darker areas were cooler.

On Jupiter, the hotter parts of the atmosphere correspond to thin clouds, while the cooler parts are covered by thicker clouds that block more of the heat emanating from Jupiter's superheated core.

The researchers then tracked the movement of the clouds and filaments over the 30-second intervals between photos to calculate horizontal wind speeds.

These two pieces of information allowed the scientists to apply methods from ocean and atmospheric science to Jupiter to calculate vertical wind speeds that correspond to the temperatures and horizontal wind speeds the researchers derived from the images.

Calculating vertical wind speeds, they found that Jupiter's filaments do in fact move like Earth's fronts.

The vertical wind speeds at the edges of Jupiter's fronts also mean that the fronts transport energy in the form of heat from the planet's hot interior to the upper atmosphere, potentially generating large cyclones.

Although convection is the primary driving force, fronts account for a quarter of the total kinetic energy powering Jupiter's cyclones and 40 percent of the vertical heat transport.

“These cyclones at Jupiter's poles have continued since they were first observed in 2016,” Dr Siegelman said.

“These filaments between the larger vortices are relatively small, but they are a key mechanism for maintaining cyclones.”

“It's intriguing that fronts and convection exist and influence Earth and Jupiter, suggesting that these processes may also exist on other turbulent fluid bodies in the universe.”

“Jupiter's enormous scale and Juno's high-resolution images allow us to more clearly visualize how small-scale phenomena like fronts connect with larger-scale phenomena like cyclones and the atmosphere. These connections are often difficult to observe on Earth because they are much smaller and more ephemeral.”

“But the long-awaited new satellite, SWOT, will make observing these ocean phenomena much easier.”

“There's a kind of cosmic beauty in knowing that these physical mechanisms on Earth exist on other planets far, far away.”

Team paper Published in the journal Natural Physics.

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L. Siegelman & P. ​​Klein. Frontogenesis at high latitudes on Jupiter. National Physical SocietyPublished online June 6, 2024; doi: 10.1038/s41567-024-02516-x

Source: www.sci.news

The Melting of Polar Ice Could Alter Earth’s Rotation and Timekeeping.

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Global warming is causing the Earth’s rotation to slow slightly, which could affect the way we measure time.

A study published Wednesday found that the melting of polar ice, a trend accelerated primarily by anthropogenic climate change, is causing the Earth to spin more slowly than it would otherwise.

Study author Duncan Agnew, a geophysicist at the Scripps Institution of Oceanography at the University of California, San Diego, said melting polar ice changes where the Earth’s mass is concentrated. This change affects the planet’s angular velocity.

Agnew likened the dynamic to a figure skater spinning around on ice. He said, “If a skater starts spinning and lowers his arms or extends his legs, he will slow down.” However, if the skater’s arms are pulled inward, the skater will rotate faster.

So less solid ice at the poles means more mass around the equator, at the Earth’s waist.

“What melting ice does is take water that has solidified in places like Antarctica or Greenland, and when that frozen water melts, it moves that liquid to other parts of the planet. “Thomas Herring said. He was a professor of geophysics at the Massachusetts Institute of Technology but was not involved in the new research. “Water flows toward the equator.”

In other words, this study shows how human influence can successfully manipulate forces that have puzzled scholars, stargazers, and scientists for millennia: forces long thought to be constants beyond human control. It suggests that it has happened.

“It’s kind of impressive, even to me, that we were able to accomplish something that measurably changed the rotational speed of the Earth,” Agnew said. “Something unprecedented is happening.”

His research, published in the journal Nature, suggests that climate change is playing a significant enough role in the Earth’s rotation to delay the possibility of a “negative leap second.” If the polar ice hadn’t melted, clocks around the world might have needed to subtract one second by 2026 to synchronize universal time with the Earth’s rotation, which is influenced by a variety of factors.

Rather, the impact of climate change has delayed that outlook by an estimated three years. If timekeeping organizations ultimately decide to add negative leap seconds, the adjustment could disrupt computer networks.

A view of the Earth captured by a deep space climate observation satellite.NASA

The leap second adjustment is necessary because even without climate change, the Earth’s daily rotation tends to slow down over time, even though it appears constant.

Studies show that about 70 million years ago, days became even shorter, lasting about 23.5 hours. Implications of paleoceanography and paleoclimatology. This means that Cretaceous dinosaurs experienced 372 planetary days a year.

Several important factors influence a planet’s rotation, but they sometimes act in opposition.

Due in part to the moon’s gravitational pull, tidal friction in the oceans slows the Earth’s rotation. Meanwhile, since the last Ice Age, the Earth’s crust has been uplifting in some areas in response to the removal of ice sheet weight. This effect changes the distribution of mass, causing the planet to spin faster. Both of these processes are approximately constant and have predictable rates.

Yet another factor is the movement of fluids within Earth’s liquid inner core, a wild card that can either speed up or slow down Earth’s rotation, Agnew said.

Here, melted polar ice was added to the mix. As climate change intensifies, researchers expect melting ice to have an even more profound effect on the Earth’s rotation.

“As we predict, as melting accelerates over time, its contribution will become even larger,” Herring said. He added that the new study is a thorough and robust analysis that combines research from multiple scientific fields.

The need for timekeepers to adjust universal time to match the Earth’s rotation is not a new phenomenon. But historically, this involved adding leap seconds to the common standard for clocks. This is because astronomical time lags behind atomic time (measured by the vibrations of atoms in atomic clocks) due to the slowing of the Earth’s rotation.

But in recent decades, changes in the Earth’s core have caused the Earth to rotate faster than expected. This has led timekeepers, for the first time since Coordinated Universal Time was officially adopted in the 1960s, to consider whether it makes sense to subtract leap seconds to synchronize universal time with the Earth’s rotation. Ta.

The melting of polar ice counteracted that trend, avoiding any decision points regarding negative leap seconds. According to Agnew’s estimates, if the current rate of Earth’s rotation is maintained, it will likely be delayed by three years from 2026 to 2029.

Adding or subtracting leap seconds is troublesome because it can disrupt satellite, financial, and energy transmission systems that rely on very precise timing. For that purpose, Timekeepers around the world have voted to abolish leap seconds in 2022. By 2035, addition and subtraction will shift universal time from the pace of the Earth’s rotation.

“Since around 2000, there has been a movement to abolish leap seconds,” Agnew said.

Regardless of whether the clocks ultimately change, the idea that melting polar ice is affecting the Earth’s rotation speaks to how important an issue it has become. Studies have already shown that ice loss has significant impacts on coastal communities.

Scientists predict that sea level rise will accelerate as the climate warms, a process that will continue for hundreds of years. Last year, leading polar researchers warned in a report that parts of the major ice sheets could collapse and coastal regions should brace for several feet of sea level rise. If humans allowed global average temperatures to rise by 2 degrees Celsius, Earth could see sea levels rise by more than 40 feet.

Source: www.nbcnews.com

Photo of a polar bear snoozing on an iceberg captures attention and admiration

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Nima Sarikani/Wildlife Photographer of the Year

As midnight approaches in Svalbard, a young polar bear climbs onto an iceberg, makes himself a makeshift bed, and falls asleep. This year’s winner, Nima Sarikani, captured this peaceful moment that captures the essence of Earth’s fragility. Wildlife Photographer of the Year, People’s Choice Awarddecided by public vote.

Sarikani, from the UK, spent three days exploring Norway’s Svalbard archipelago in hopes of catching a glimpse of these iconic arctic animals. After the expedition vessel decided to change course, he was finally able to see both the older and younger males. Salikhani seized the opportunity to photograph a young bear dozing on an iceberg. This scene not only evokes the bond between animals and their habitat, but also the need to act against global challenges such as climate change and habitat loss.

These days, the sight of a lone polar bear on melting ice has become a familiar symbol of the effects of climate change. But there are good reasons for this. Global warming is affecting the Arctic particularly rapidly, where temperatures are rising three times faster than the global average. Bears are among the hardest hit, and are increasingly threatened by the loss of sea ice on which they depend for hunting and raising their young.

Salikhani is optimistic that while his shots are meant to stir the emotions of viewers, they will ultimately give polar bears hope that if they do the right thing, it’s not too late.The image will appear like this exhibition It will run until June 30th at the Natural History Museum in London, with four runners-up in the competition.

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Source: www.newscientist.com

Newly Found Fossil Remains in France Offer Valuable Information on Ordovician Polar Ecosystems

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in new paper in diary natural ecology and evolution, paleontologists described the diversity of the Cabrières biota, a new Early Ordovician site in the Montagne Noire in southern France. During the Early Ordovician, this region was an open marine environment located in the southern hemisphere at high polar latitudes, on the margin of the Gondwana supercontinent.

Artistic reconstruction of Cabrière Biota: in the foreground, Unpix (trilobites) and various ostracods including brachiopods and cryoliths (bottom left corner). Behind the trilobites are lobopods, chelicerates, cnidarians (blue), sponges (green), thin branched algae (red and green), hemichordates (purple), and some soft bodies. There are animals. Bivalve arthropods live in the water column along with graptolites. Image credit: Christian McCall, Prehistorya Art.

“Early Paleozoic sites with preserved soft tissues provide a wealth of information about the evolution of past life and improve our understanding of earlier ecosystems, but they are unevenly distributed in time and space. ,” said paleontologist Farid Saleh of the University of Lausanne and his colleagues.

“About 100 soft-tissue preserved assemblages have been recorded from the Cambrian, while about 30 are known from the Ordovician, and only a few have been discovered in early Ordovician rocks. .”

“The distribution of early Paleozoic remains is also paleogeographically biased, as approximately 97% of the biota discovered represents tropical and temperate ecosystems within 65 degrees north and south of the paleoequator.”

“This pattern is especially true for the Ordovician, where very few sites are known to have polar environments.”

“Among the most famous Ordovician sites, Sumchere in South Africa, Big Hill in the United States, and Winneshiek exhibit tropical ecosystems.”

“Given the rarity of Ordovician sites and their lopsided paleogeographical distribution, discovering new biota with preserved soft tissues across the aforementioned paleogeographic zones and environments will deepen our understanding of this period and This is crucial for gaining better insight into the factors driving increases in animal diversity on Earth. ”

Biomineralized species of the Cabriere biota: (a) Trilobites of the genus Unpix(b) gastropods with tubular structures, probably conuraids Sphenothalas(c) biomineralized canine cnidarians; (d) Arthrobrachiopod attached to a spongiosa, probably of the leptomid family. (e) Assemblage formed by an articulated brachiopod (center), a flattened carapace of a probably bivalve arthropod (left and right of center), and the skull of a calimenin trilobite (left). (f) Possibly visceral cyst. Scale bars – (a) and (e) 4 mm, (b) and (d) 1 cm, (c) 5 mm, (f) 2 mm.Image credit: Saleh other., doi: 10.1038/s41559-024-02331-w.

In a new paper, paleontologists describe a group of 470-million-year-old (early Ordovician) fossils, named Cabrière Biota, discovered in southern France's Montagne Noire.

The fossil site was discovered by two French amateurs, Eric Montseret and Sylvie Montseret Goujon.

Saleh and his co-authors examined about 400 extremely well-preserved soft tissue fossils taken from the site.

Fossils typically exhibit shades of brown, red, or orange and are embedded within a siliciclastic matrix of mudstone and siltstone, and their colors range from blue to green to yellow.

The Cabriere biota is characterized by a prevalence of sponges and branched algae, which constitute 26% of all identified fossils.

Also included are molluscs (14%), trilobites (12%), brachiopods (9%), cystoliths (7%), and cnidarians (6%).

An interesting feature of this biota is its rarity, with echinoderms being represented by only three specimens.

The Cabrières biota also exhibits the shells of various bivalve arthropods, which constitute 16% of the fossils identified.

Some wormlike organisms are also present in the biota (approximately 1% of identified fossils).

“The Cabrière biota was once located in close proximity to Antarctica and reveals the composition of the southernmost Ordovician ecosystem,” Dr Saleh said.

“The high biodiversity of this site suggests that the area served as a refuge for species fleeing the high temperatures that were prevalent further north at the time.”

“During this period of global warming, animals were certainly living in high-latitude refuges, escaping the extreme temperatures at the equator.”

Dr Jonathan Antcliffe, a paleontologist at the University of Lausanne, said: “The distant past gives us a glimpse of the near future that could happen to us.''

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F. Saleh other. Cabrières Biota (France) provides insight into Ordovician polar ecosystems. Nat Ecole Evol, published online on February 9, 2024. doi: 10.1038/s41559-024-02331-w

Source: www.sci.news

Stay Warm in the Coldest Weather with a Polar Bear Fur Sweater

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Polar bear fur keeps animals warm even in arctic temperatures

Torsten Milse/Robersarding/Alamy

Fibers said to mimic polar bear fur may one day be used in the next generation of spacesuits, military uniforms and clothing for extremely cold environments.

Under the guidance of developers at China’s Zhejiang University, this man-made fiber has already been made into sweaters and is claimed to be as warm as down feathers, the best-known natural insulator. It’s just a small part of that warmth. thickness.

The researchers make claims about the sweater’s strength and stretch in their paper, but not everyone is convinced they’ve presented enough data to back them up.

HaobaiPolar bear fur consists of a highly porous core and a dense shell, team members said. “The porous structure traps large amounts of air to block heat transfer, and the dense shell provides the hair’s mechanical strength,” he says.

Man-made fibers, on the other hand, are composed of “aerogels,” materials with low density, high porosity, and high air content (more than 90 percent by volume) encased in a rubberized exterior.

In addition to being warm, the researchers tested the fabric for practicality by subjecting it to 10,000 stretching cycles and reported no loss of structure. It has an elasticity of up to 1,600 percent and is strong enough that a single fiber can lift a mass of 500 grams.

Sweaters knitted with this fiber are “about one-fifth as thick as down for the same warmth, and are easier to wash and dye,” the researchers wrote in their paper. “Such fibers have excellent insulation and multifunctionality, and have great potential in areas such as military uniforms and spacesuits used in extremely cold environments.”

lisa lake According to a research team at Australia’s University of Technology Sydney, people have long been interested in how polar bear fur keeps the animals warm in such frigid temperatures, and researchers are looking to create a synthetic It appears they have found a way to mimic that property using materials.

but christopher hullen Researchers from Australia’s Deakin University also question the claims based on the limited data presented.

There are also many animals with hollow fur similar to polar bears, such as beavers, camels, and the Australian green possum. One of the biggest benefits of polar bear fur is not its structure, but the transparency of the fibers, which reduces heat radiation.

“It’s a nice idea, but does it really mimic polar bear fur?” says Hulen. “Probably not.”

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Source: www.newscientist.com

Utilizing DNA from Polar Bear Snow Tracks to Support Conservation efforts

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Researchers have developed a breakthrough method to protect polar bears by analyzing DNA from footprints in the snow. This non-invasive technique can also be applied to other snow-dwelling animals such as lynx and snow leopards, providing a safer and more efficient way to collect data essential to wildlife conservation.

Scientists have discovered a way to capture DNA Observations from snow tracks – a promising non-invasive way to monitor elusive animals like polar bears.

The polar bear is a symbol of the Arctic, an elusive and vulnerable animal. Close monitoring of polar bear populations is critical to polar bear conservation, but polar bears are so difficult to find that critical data about population size and connectivity between those populations is lacking. I am. Scientists have now developed a helpful new tool: DNA analysis using skin cells shed from bear tracks in the snow.

Dr Melanie Lancaster of the World Wildlife Fund’s Global Arctic Program said: ‘Finding polar bears in the Arctic, let alone counting them and understanding how they are coping with climate change, is particularly difficult. “And it’s expensive and time-consuming.” , senior author of the study Frontiers of conservation science.

Innovative forensic techniques in preservation

The scientists were inspired by forensic techniques that can be applied to trace amounts of degraded DNA samples. These techniques eliminate the need to physically capture bears, which can be stressful and dangerous for both bears and humans, and is a concern for some local indigenous communities. Instead, scientists can look at the source of accidentally released DNA: environmental DNA.

A polar bear in Utchagvik, Alaska.Credit: Elizabeth Kruger, World Wildlife Fund

“Many Inuit have expressed concerns about invasive research methods,” said the article’s author, Elizabeth Krueger of the World Wildlife Fund. “People are concerned about the welfare of individual polar bears and the health and safety of those who may later harvest the bears. This is one reason we are so excited about new methods like this. The person collecting the samples does not need to see or even be seen by the polar bear.”

Environmental DNA: a non-invasive tool

A common form of environmental DNA is deposited when animals defecate. However, the quality of DNA is not always sufficient for the individual-level analysis required for preservation. Furthermore, in the case of territorial animals like her other two, seed Scientists tested lynx and snow leopards, and the collection of faeces can affect the animals’ behavior. So the researchers focused on the skin cells in snowy footprints.

“Trucks typically contain fresh cells and the DNA is intact due to the cold ‘storage’ temperatures. “The DNA that passes through the intestine is further degraded, making it more difficult to study,” said lead author Dr Michaela Helström from MIX Research Sweden AB.

Real-world tracking and sampling

The researchers collected snow from individual footprints made by polar bears in Alaska and Eurasian lynx in Sweden in the wild and in captivity. They also collected snow from footprints made by captive snow leopards. Additional substances such as hair, saliva, and mucus were also sampled to ensure that the traces yielded accurate genotypes.

Twenty-four wild polar bear tracks and 44 wild lynx tracks were sampled. The researchers melted and filtered the snow to collect environmental DNA and analyzed the microsatellites. Although the concentration of DNA recovered from footprints collected in the wild was very low, we were able to recover nuclear DNA from 87.5% of wild polar bear footprints and 59.1% of wild lynx footprints. We were able to genotype 13 of the wild polar bear samples and identify 12 different individuals.

They were able to genotype 11% of the lynx footprints, but this percentage increased significantly when scientists examined only footprints sampled by trained personnel. They were able to recover nuclear DNA from 76% of the samples collected by trained personnel and genotype 24% of the samples.

A step-by-step approach

This technology has great potential to inform conservation of these animals, better understand animal populations and behavior, and manage conflicts with humans through accurate animal identification. Although non-invasive sampling has a low success rate, it is easy to collect and can greatly expand sample size.

“We hope this method will be adopted by the polar bear research community as a new way to collect information about polar bears, with the participation of hunters, volunteers, and indigenous communities,” Lancaster said. “We also hope that this method can be extended to other animals that live in snowy environments. We have started by showing that this method works for lynx and snow leopards as well. I did.”

Reference: “Capturing environmental DNA from snow tracks of polar bears, lynx, and snow leopards for individual identification” Michaela Hellström, Elisabeth Kruger, Johan Neslund, Mia Bister, Anna Edlund, Patrick Hernvall, Viktor・Birgerson, Rafael Augusto, Melanie L. Lancaster, October 11, 2023. Frontiers of conservation science.
DOI: 10.3389/fcosc.2023.1250996

Source: scitechdaily.com