23.06.2022
‘Stretching’ of the continents 56 million years drove global warming, study finds

Stretching of the continents 56 million years ago is likely to have caused one of the most extreme episodes of global warming in Earth’s history, new research suggests.

During this time, the planet experienced an increase in temperature of 5-8°C (9-14°F), culminating in the Paleocene-Eocene Thermal Maximum (PETM), which lasted about 170,000 years.

It caused the extinction of many deep-sea organisms and reshaped the course of evolution of life on Earth.

Scientists studied the effects of global tectonic forces and volcanic eruptions during the period of environmental change almost 60 million years ago.

They believe that the extensive stretching of the continental plates in the northern hemisphere – rather like the pulling of a toffee bar that thins and eventually separates – massively reduced the pressures in the Earth’s deep interior.

This then drove intense, but short-lived melting in the mantle – a layer of sticky, molten rock just below the planet’s crust.

The team, including experts from the universities of Southampton, Edinburgh and Leeds, suggests that the resulting volcanic activity coincided with, and likely caused, a massive burst of carbon release into the atmosphere linked to PETM warming.

Dr Tom Gernon, an associate professor of Earth science at the University of Southampton and lead author of the study, said: ‘Despite the importance and wider relevance of the PETM to global change today, the underlying cause is highly debated.

‘It’s generally agreed that a sudden and massive release of the greenhouse gas, carbon, from the Earth’s interior must have driven this event, yet the scale and pace of warming is very hard to explain by conventional volcanic processes.’

The scientists found evidence from rock drilled from the seafloor for a widespread episode volcanic activity lasting 200,000 years, which coincided with the PETM.

Using archives of rock drilled beneath the seafloor near the edge of the Atlantic Ocean, the team found evidence of an abrupt and widespread episode of volcanic activity across the North Atlantic Ocean that lasted just over 200,000 years, strikingly similar to the duration of the PETM.

This finding prompted the researchers to investigate a broader expanse of the North Atlantic region, including Greenland and the Faroe Islands.

Here, they found that kilometre-thick piles of lava that started to erupt just before the PETM show unusual compositions that point to a significant increase in the amount of melting of the uppermost solid part of Earth’s mantle beneath the continent.

Dr Gernon said this would have led to a rapid increase of carbon being released, which would have led to the global warming.

The intense volcanic activity occurred just as the continental landmass that united Greenland and Europe was most intensely stretched by plate tectonic forces.

Eventually, North America and Greenland finally separated from Europe, leading to the birth of the North Atlantic Ocean.

Scientists believe it was this final phase of stretching that brought about substantial melting in the Earth’s mantle, leading to massive carbon release, and in-turn, global warming.

Dr Thea Hincks, senior research fellow at the University of Southampton and co-author on the study, said: ‘Using physically realistic estimates of the key characteristics of these volcanic systems, we show that the amount of carbon needed to drive warming could have been attained by enhanced melting.’

Dr Gernon added: ‘Such rapid events cause a fundamental reorganisation of Earth’s surface environment, altering vast ecosystems.’

The study has been published in the journal Nature Geoscience.

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  • 4 часа, 50 минут назад 29.06.2022Science
    Megalodon feasted on the noses of sperm whales

    Megalodon — the biggest shark that ever lived — ate sperm whales because it was attracted by their huge noses, a new study claims.

    Measuring up to 65ft long and weighing an estimated 100 tonnes, the prehistoric predator was one of the most ferocious animals when it swam in oceans around the globe between 23 and 3.6 million years ago.

    The sperm whale’s enormous snout, which makes up a third of its body, was particularly appealing to megalodon because it is packed with oily saturated fats, according to researchers at the University of Zurich.

    Their findings are based on analysis of 7 million-year-old fossilised sperm whale skulls from southern Peru.

    A series of bite marks indicate that sharks consistently fed on them.

    Lead author Aldo Benites-Palomino, a palaeontology student at the University of Zurich, said: ‘These are concentrated along the nose, mouth and face.

    ‘In sperm whales, these regions receive most of their greatly enlarged nasal organs that are responsible for the sound production and emission system.

    ‘The main organs of this complex are the spermaceti and the melon, structures rich in fats and oils, but also heavily regulated by the facial muscles.

    ‘Most of the bite marks have been found on the bones that would be adjacent to these soft tissue structures, such as the jaws, or around the eye, thus indicating that sharks actively targeted this region.’

    The sharks that attacked sperm whales ranged from megalodon — meaning big-tooth — to species that are still around today, including mako sharks, sand sharks and the Great White.

    Megalodon even attacked prehistoric sea monster Leviathan melvillei — named after the author of Moby Dick, say scientists.

    Half a dozen skulls were unearthed at the Pisco Formation in the Ica Desert.

    It is famous for a treasure trove of Miocene shark and ray remains, bony fishes, turtles, marine crocodiles, seabirds, whales and seals.

    In the oceans, the Miocene was a time of changing circulation patterns, probably due to global cooling.

    It spanned 23 million to five million years ago. By the end of it, almost all modern groups of whales had appeared.

    Benites-Palomino said: ‘Sperm whales are a group characterised by their greatly enlarged, and rich in fat, nasal organs, which they use for sound production.

    ‘Here, we report several fossil sperm whale skulls from the Pisco Formation that display a similar pattern of shark bite marks.

    ‘These are located across the skull regions which housed these organs, indicating a feeding preference by sharks over these nasal organs.

    ‘Such a feeding pattern has no modern preference and suggest the broad diversity of Miocene sperm whales served as a fat repository for prehistoric sharks.’

    During the last 30 years, explorations carried out in the area have also unveiled aquatic sloths and even walrus-faced dolphins.

    Benites-Palomino said: ‘It indicates a rich and diverse ecosystem seven million years ago.

    ‘Warmer oceanic water temperatures combined with a series of protected coastal environments greatly benefited the marine fauna.

    ‘Among these, sperm whales and sharks were some of the most abundant and conspicuous groups around.

    ‘During the last decade palaeontologists across the globe have been inquiring about the interactions between these two large groups of marine predators.’

    The researchers hope their study could shed light on the connections between them.

    Benites-Palomino said: ‘The overall shape, size and arrangement of the bite marks is greatly variable, suggesting more than one species of shark was targeting the sperm whales.’

    Today, sharks seek the carcasses of baleen whales with high concentrations of fats, such as the blubber.

    ‘During the Miocene baleen whales were small, but sperm whales would have constituted a perfect fat repository due to their greatly enlarged and lipid-rich nasal organs,’ Benites-Palomino added.

    Megalodon and Leviathan died out about three million years ago during the period of global cooling, but the reasons for their demise are still being debated.

    The new study has been published in the journal Proceedings of the Royal Society B: Biological Sciences.

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  • 6 часов, 50 минут назад 29.06.2022Science
    SpaceX’s Starship Super Heavy rocket, which is the world’s tallest, is ready for launch pad tests

    SpaceX Starship’s Super Heavy Rocket is ready for what could be its final launch pad test before a likely orbital test flight in July.

    The massive Super Heavy Booster 7, which has 33 Raptor engines, was transported to its orbital launch pad on June 23.

    An enormous robotic arm mounted the rocket to the launch pad.

    A huge amount of work was required for the company to reach this point due to the large number of Raptor rocket engines in the Super Heavy.

    Scroll down for video

    As Ars Technica notes, Aerojet Rocketdyne, which also makes propulsion rockets, has a goal of building just four RS-25 rocket engines for NASA this year.

    In contrast, Musk’s company is now building at least four Raptor rocket engines per week. The two different engines are comparable in terms of their power.

    The South Texas site contains a huge ‘launch and catch’ tower that will support the fully stacked rocket during all operations.

    Shortly after the launch, it will catch the first-stage booster with massive robotic ‘chopsticks’ as the rocket slows down near the ground.

    ‘This tower, from design to construction, took 13 months,’ Musk previously said during a SpaceX presentation.

    ‘We’re aiming for rapid reusability, which is why the booster is going to take off and then fly back to the launch tower and aspirationally, land on the arms, which does sound insane,’ Musk said, explaining the “catch” part of the launch and catch tower.

    ‘If it does come in too fast and shear off the arms, then I guess it will be “a farewell to arms.”‘

    SpaceX, which has conducted at least 24 successful launches this year and sent everything from Starlink satellites to classified payloads into orbit, has come a long way from the its past failures.

    On June 28, 2015, a 208-foot-tall SpaceX Falcon 9 rocket that was destined for the International Space Station exploded minutes after launching from Cape Canaveral Air Force Station in Florida.

    The lost rocket reportedly carried more than 4,000 pounds of payload that included experiments, a spacesuit, a camera to record meteors streaking and a docking adapter that would’ve served as a parking spot for future crew capsules.

    It was later determined that the accident was caused by overpressure in the liquid oxygen tank of the rocket’s upper stage.

    With Musk at the helm, SpaceX has made rapid progress over the last few years.

    The tech billionaire and likely Twitter owner said Starship would be ‘ready to fly’ in July and that the company will have another Starship stack ready for August.

    If SpaceX conducts a full wet dress rehearsal – during which the booster would be filled with more than 3,000 tons of liquid oxygen and liquid methane – it would be the first for Super Heavy, reports Teslarati.

    NASA and SpaceX announced Tuesday that they’re targeting no earlier than July 14 for launch of the CRS-25 commercial resupply services mission to the International Space Station.

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  • 8 часов, 50 минут назад 28.06.2022Science
    Scientists cannot create drug for deadly pathogen that has killed THOUSANDS across 50 countries

    A deadly pathogen emerged in 2009 that scientists have yet to tackle with drugs and the reason is because it reproduces sexually.

    Most infectious bacteria reproduces asexually, meaning it creates strains that are copies of itself – allowing drugs to be made.

    However, Candida auris mate with each other and produce different strains each time.

    C. auris causes bloodstream infections, wound infections and ear infections and can sometimes result in death.

    It was first discovered in 2009 and has since spread in over 50 countries, where outbreaks have been reported and thousands have died from fungal infections.

    The study that uncovered why C. auris is multidrug-resistant was conducted by researches at McMaster University, who analyzed nearly 1,300 strains of the pathogen.

    The team searched for and confirmed recombination events, or sexual activity.

    Jianping Xu, a professor in McMaster’s Department of Biology and researcher with Canada’s Global Nexus for Pandemics and Biological Threats, said in a statement: ‘The research tells us that this fungus has recombined in the past and can recombine in nature, which enable it to generate new genetic variants rather quickly.

    ‘That may sound frightening, but it’s a double-edged sword. Because we learned they could recombine in nature, we could possibly replicate the process in the lab, which could allow us to understand the genetic controls of virulence and drug resistance and potentially other traits that make it such a dangerous pathogen, much faster.’

    There are five different clades, or lineages, of C. airus that are known worldwide.

    Clade I were isolated predominantly from South Asia, Clade II predominantly from East Asia, Clade III predominantly from Africa, Clade IV predominantly from the Americas, and several strains of Clade V from Iran in central Asia.

    ‘The five clades differ from each other by 20,000 to over 200,000 nuclear genome, reads the study published in Computation and Structural Biotechnology Journal.

    Canada is one of the countries that has three of the five known divergent lineages and researchers note some came from the same hospital.

    Xu explains that if one strain becomes resistant to one drug and another strain becomes resistant to another drug, then through sexual activity they could produce offspring resistant to both drugs.

    ‘The mixing of strains in the same hospital, potentially in the same patient, creates an opportunity for them to meet and mate,’ he said.

    ‘This study is about sex and the implication of sex to organisms is often very broad. For fungi, it means they can spread genes that are beneficial to them much faster through populations than asexual reproduction alone.’

    Little is known about C. auris, which is also hard to identify in samples.

    But what is known, is that those who spend time in nursing homes or have lines and tubes in their body are more at risk of being infected.

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  • 10 часов, 50 минут назад 28.06.2022Science
    Spotify is quietly testing a new ‘karaoke mode’ that judges how well you sing

    Spotify has quietly begun testing a new ‘karaoke mode’ that lets users sing along to songs and then gives them a score based on their vocal skills.

    Karaoke mode has not been officially announced by the company, but several users have shared screenshots of the new feature on social media.

    It appears to build on the existing ‘Lyrics’ feature, which was released last year and allows Spotify users to track lyrics that scroll in real time as songs are playing.

    Users who already have access to the new karaoke feature claim that a ‘Sing’ button with a microphone icon appears in the top right corner of the lyrics panel.

    Pressing the button causes the original vocals to be muted, but the backing track to continue playing, so that users can show off their vocal skills.

    Once the song is over, the user is given a percentage ‘accuracy score’, along with a motivational message such as ‘You’re on the road to become famous!’

    It is not clear how the feature works – causing some users to speculate that Spotify employees are listening to their singing attempts through their smartphone microphones.

    The more likely explanation is that the company is using AI to match the user’s pitch with the song’s original score.

    However, the company isn’t giving anything away.

    When asked for more information by MailOnline, a spokesperson for the company simply said: ‘At Spotify, we routinely conduct a number of tests in an effort to improve our user experience.

    ‘Some of those end up paving the path for our broader user experience and others serve only as important learnings.

    ‘We have no further news to share on future plans at this time.’

    How to get Karaoke mode on Spotify

    There appears to be no way to get access to the feature, apart from waiting for an app update.

    This has led to frustration among karaoke fans who are desperate to try out the new tool.

    You can check if you already have access to the feature by selecting the song you want to listen to, then scroll down to find the lyrics.

    If you are part of the trial, you will see a button labelled ‘Sing’ in the top right corner of the lyrics tab.

    Once you’ve hit the button, a different style of lyrics screen will pop up showing the words line-by-line – just like a karaoke machine.

    If the Sing button isn’t there, you could try checking for updates on the App Store or Google Play, but even if you download an update this does not guarantee you will get access.

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  • 10 часов, 50 минут назад 28.06.2022Science
    Stunning Roman mosaic featuring wild animals and marine scenes returns to Israel after tour

    A gorgeous and detailed Roman mosaic has come back home to Israel after more than ten years touring major museums worldwide.

    The 1,700-year-old mosaic was initially discovered by accident in 1996 by Miriam Avisar from the Israeli Antiquities Authority (IAA) during a dig that was trying to save archaeological finds in a squite on HeKhalutz St. in Lod.

    It took another 13 years for it to be fully unearthed by researchers.

    ‘It was the biggest and most impressive and unique mosaic discovered in Israel,’ Mark Avrahami, head of the IAA Art Conservation Unit, said Monday at the dedication ceremony of the Shelby White and Leon Levy Lod Mosaic Archaeological Center, according to the Jerusalem Post.

    Scroll down for video

    The mosaic measures 56 feet by 30 feet – quite massive.

    It features a collection of animals, including an African elephant, rhinoceros and giraffe.

    ‘It is very impressive in its artistic style, and its state of preservation was perfect,’ Avrahami said, adding that the mosaic details includes shadows of the animal images as well as blood dripping from a bull in one panel depicting a hunting or fighting scene with a lion.

    The artwork’s new home is at the Shelby White and Leon Levy Mosaic Lod Archaeological Center.

    That space offers guided tours and interactive exhibits in Arabic, English and Hebrew.

    The upper-class villa that the mosaics adorned in the third or fourth centuries underwent renovations and additions over the years as different empires took over the region.

    An earthquake in the year 749 CE took down the entire villa.

    When the mosaic was first uncovered, the authorities opened it to the public during a single weekend over the course of which 30,000 people traveled to Lod to see it.

    The mosaics were displayed over the years at many institutions, including New York City’s Metropolitan Museum of Art, the Pennsylvania Museum of Archaeology, the Louvre Museum in Paris, Chicago’s Field Museum, and the the Hermitage in St. Petersburg, Russia.

    Researchers are hopeful that it can become a major tourist attraction in a part of the world often riven with conflict.

    ‘Community tourism in an area of conflict is both an extraordinary experience for the tourist, and an opportunity for the local people to tell their story to the world,’ Yossi Graiver, head of the JLM TIM tourism group, which runs the mosaic museum, told the Post.

    ‘It’s also an opportunity to develop tourism based on circular economics: people will set up tourism-based businesses telling their stories to the world.’

    ‘That mosaic isn’t Jewish, Christian or Islamic. Everybody can love it.’

    Although the names of the artisans who created the mosaic are unknown, IAA senior research archaeologist Hagit Torge said it would’ve been made by a famous groups of artists who were prevalent in that region and made similar works in other cities.

    ‘This is the Rolls Royce,’ she said. ‘This is the most visually impressive mosaic we have found. This is the whole point of archaeology – not just the structures, but trying to understand the people who built them and lived in them, their social structure and environmental relations.’

    Shelby White, who helped to make the museum happen – along with the Leon Levy Foundation, the IAA and the municipality of Lod – called the new space a ‘dream come true.’

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  • 10 часов, 50 минут назад 28.06.2022Science
    Invasion of the ‘rock snot’: Gooey algae that suffocates organisms are infecting Michigan waterways

    Gooey ‘rock snot’ that suffocates organisms living on the bottom of rivers and streams is invading Michigan waterways.

    Formally known as didymo, this algae creates a mat that can grow over six inches thick and some have been observed to be two-feet-long.

    While non-toxic, rock snot reduces habitat for macroinvertebrates that are an important food for the underwater ecosystem.

    The algae can also survive for 40 days in cool, dark, damp conditions such as on angling equipment, neoprene and felt-soled waders and boots – anglers are encouraged to clean gear in Michigan after every use.

    Didymo flourishes in cold water and sprout stalks ‘under really low-nutrient conditions,’ Ashley Moerke, Lake Superior State University (LSSU) professor and director of the new Center for Freshwater Research and Education (CFRE), told MLive.

    Despite its nickname, didymo does not feel slimy, but has a wet wool-like texture.

    But it appears like goop as it clings to rocks and underwater plants.

    Another issue of this invader is its ability to choke organisms that are food for other fish – specifically trout that are already threatened in Michigan.

    And although didymo was first spotted in 2015, scientists are still working to figure out what triggers its blooms.

    According to Michigan State ANR, researchers are still working to figure out what triggers didymo’s nuisance blooms.

    They speculate that it is a result of changing environmental conditions, or it could be didymo spreading to new waterways on fishing gear, which is the common way nuisance species spread.

    Researchers in Canada are connecting the large blooms to climate change; ice melting off the rivers earlier in the year and sooner springtime vegetation growth means fewer nutrients are naturally draining off into waterways.

    ‘That’s suggesting that if the land is holding the nutrients, there might actually be a decline in nutrients that’s causing these blooms. There’s some potential evidence for this in in the St. Marys River,’ Moerke said.

    LSSU officials are also researching how the algae blooms impact macroinvertebrates and fish populations as an organism that is ‘reengineering the habitat.’

    ‘There’s been a strong demonstration that macroinvertebrate communities have changed. What we haven’t been able to really determine well is the impacts on fish. There haven’t been nearly as many studies … because it’s much more difficult. Fish are very mobile. They can move out of a habitat,’ Moerke said.

    The Manistee River, located in the lower peninsula of Michigan, is currently infested with the gooey algae.

    Ann Miller, an aquatic biologist and avid Manistee River fly fisher, told 9and10news: ‘Right now, didymo is a big puzzle with a lot of people working to address it. We need to find out why it’s showing up where it is and more importantly, how best to decontaminate gear to prevent it from spreading.

    ‘Right now, many local fishing guides are doing their best to avoid the stretch of the Manistee where didymo is blooming but fishing is their livelihood.

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Science 'Stretching' of the continents 56 million years drove global warming, study finds