Tag Archives: ocean

Titan’s underground ocean revealed by Cassini observations

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Titan, Saturn’s largest moon, harbors an ocean of low-density water or ammonia inside, according to an analysis of archival data from NASA’s Cassini mission.

A representation of Cassini’s orbit used to calculate Titan’s gravity. The colored part of the orbit shows the distance from Cassini to Titan, with the minimum distance shown in red. A cross-section of Titan shows the moon’s different layers and blue oceans. In the background you can see Saturn with its rings and ring shadows. Image credit: Britt Griswold, NASA Goddard Space Flight Center.

“Liquid water is one of the prerequisites for life,” said Dr. Sander Goossens of NASA’s Goddard Space Flight Center and colleagues.

“Water is rarely liquid on the surfaces of planets, but many moons of the solar system, such as Titan, have underground oceans.”

“These probably formed a long time ago, which begs the question why they haven’t already frozen in a cold environment far from the sun.”

“Our study supports the explanation that ammonia extended the life of Titan’s liquid oceans. Additionally, it also provides insight into Titan’s deeper layers.”

NASA’s Cassini mission explored Saturn and its icy moons for more than a decade.

Among its many instruments, Cassini carried a radio science subsystem that enabled radiation tracking of Earth-based spacecraft by the Deep Space Network.

These data were used to determine the gravitational field and internal structure of some of Saturn’s moons and Saturn itself. Cassini data was also used to determine Titan’s tidal response.

“The Cassini space probe flew around Saturn from 2005 to 2017,” the researchers said.

“Probes have been sent close to the moon many times to accurately measure Titan’s gravity.”

“Cassini needed to skim past Titan at exactly the right time to properly map the changes in gravity.”

“This is because Titan’s deformation is due to Saturn’s tidal forces, and the tidal forces depend on the distance between Titan and Saturn.”

“Measurements taken when Titan was close to Saturn and when it was far away maximized the difference in Titan’s deformation, and therefore its impact on gravity.”

Scientists calculated Cassini’s speed from precise radar measurements and calculated changes in gravity and the resulting deformation of Titan.

They carefully examined the tidal effects on Titan at each location on the spacecraft’s orbit and concluded that the deformation was smaller than previously calculated.

According to numerical simulations of the moon’s deformation for different internal structures, the most likely scenario is that the ocean has a density similar to water and contains small amounts of ammonia.

“The subsurface ocean may help transport organic matter from the moon’s rocky core to the surface,” the authors said.

“It was thought that Titan’s thick layer of ice between its ocean and its core made this difficult.”

“Our analysis suggests that the ice layer may be thinner than previously thought, and that material exchange between the rock and the ocean is more likely.”

“The organic molecules this produces are considered important ingredients for the emergence of life.”

of study It was published in the magazine natural astronomy.

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S. Goossens other. A low-density ocean inside Titan estimated from Cassini data. Nat Astron, published online March 21, 2024. doi: 10.1038/s41550-024-02253-4

Source: www.sci.news

Scientists uncover five previously unknown hydrothermal vents in the Pacific Ocean

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Scientists on board the research vessel atlantis Five new deep-sea hydrothermal vents have been discovered on the ocean floor at a depth of 2,550 meters (1.6 miles). All exhaust fluids are hotter than 300 degrees Celsius (570 degrees Fahrenheit).

vehicle carried by humans alvin Arrived at the ocean floor. Image credits: J. McDermott, Lehigh University / T. Barreyre, CNRS / R. Parnell-Turner, Scripps Institution of Oceanography / D. Fornari, Woods Hole Oceanographic Institution / National Deep Diving Facility / Alvin Group.

Hydrothermal vents are rich in chemicals that provide energy for animal life, fueling rich and productive ecosystems.

The location of the new hydrothermal vent was discovered by a team of scientists during a research expedition funded by the National Science Foundation.

They are located on the East Pacific Ridge near 10 degrees north latitude and are part of the trans-Earth mid-ocean ridge volcanic mountains, where two tectonic plates are breaking apart at a rate of about 11 cm (4.3 inches) per year.

Expedition researchers used underwater robots to map the area at night guard.

rear guard Retrieved each morning, high-resolution maps from the vehicle’s sensors were used to plan the day’s dives by the manned vehicle. alvinThis gives scientists a first-hand look at the complex and ever-changing environments of places like the East Pacific Rise.

“High-resolution maps are guard There is a possibility that new hydrothermal areas will be discovered soon guard will be back on deck,” said Dr. Jill McDermott, a researcher at Lehigh University.

“This gives us great goals such as: alvin And the opportunity to make multiple discoveries in one dive.”

scientists infiltrate alvin He first discovered a hydrothermal vent in 1977 while exploring an oceanic ridge north of the Galapagos Islands.

The discovery has reshaped scientists’ understanding of the conditions that can support life on Earth and elsewhere in the solar system.

“Mid-ocean ridges account for more than 75% of all volcanic activity on Earth,” said CNRS researcher Dr. Thibault Valley.

“There are thousands of these deep-sea hot springs, which together extract 10 percent of the Earth’s total internal heat.”

“We want to better understand how hydrothermal vents release heat and chemicals as they flow beneath the ocean floor, impacting global oceans.”

“new guard “Using the map, we can see vital details of lava flows erupting in the deep ocean and target them for rock sample collection, just as geologists do on land.” said Dr. Daniel Fornari, a researcher at the institute.

“These new perspectives and analysis of rock samples will help us understand how fast the lava erupted, how far it traveled, and how deep-sea lava eruptions affect hydrothermal eruptions. I guess.”

“By working together these two state-of-the-art deep-sea submersibles, we will make surprising new discoveries about how the deep sea floor is constructed in some of the harshest environments on Earth. Yes, we can,” said Dr. Ross Parnell Turner., a researcher at Scripps Institution of Oceanography.

Source: www.sci.news

Scientists are alarmed and puzzled by record-breaking ocean heat.

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Global sea surface temperatures have been breaking records every day for the past 12 months, causing concern among marine scientists.

Senior research scientist Brian McNoldy from the University of Miami’s Rosenstiel School expressed worry about the unprecedented margins by which the records are being broken. He mentioned that the current average sea surface temperatures are approximately 1.25 degrees Fahrenheit warmer than they were from 1982 to 2011, as per the University of Maine’s climate reanalyzer, which could have significant impacts on the climate and ecosystem.

While human-induced climate change is considered a contributing factor, there are likely other natural climate processes at play as well. The rise in sea surface temperatures has puzzled scientists as they are unsure of the exact reasons behind it.

The warming ocean temperatures could lead to coral bleaching, stronger hurricanes, warmer coastal temperatures, and more extreme precipitation. Researchers have observed these effects in 2023, and they fear that if the trend continues, it could have severe consequences.

Some potential factors influencing the rise in sea surface temperatures include weakening trade winds in the North Atlantic and changes in shipping regulations limiting sulfur pollution, amongst others. Researchers are trying to understand the complex interplay of these factors leading to such unprecedented temperature increases.

The warmer ocean temperatures could fuel more powerful storms and hurricanes, putting coastal areas at risk. The Atlantic Ocean and the Horn of Africa, known for producing hurricanes hitting the East Coast of the United States, are experiencing significant anomalies in sea surface temperatures.

Overall, the rising sea surface temperatures pose a serious threat to marine ecosystems and climate stability. Scientists are working to unravel the mystery behind this phenomenon to better predict and mitigate its impacts.

Source: www.nbcnews.com

Research suggests that Mars enhances Earth’s deep ocean circulation

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Australian and French geoscientists have used the geological record of Earth's deep ocean to discover a link between our home planet and the orbit of Mars. They discovered a surprising 2.4 million-year cycle of increase and decrease in deep ocean currents, which they found was related to periods of increased solar energy and climate warming.

This image from Mars Express' high-resolution stereo camera shows the Martian Earth set against a dark background. The planet's disk is speckled with yellow, orange, blue, and green, giving it an overall muted shade of gray, representing the varying composition of its surface. Image credit: ESA / DLR / FU Berlin / G. Michael / CC BY-SA 3.0 IGO.

“In 1976, scientists first demonstrated and confirmed the presence of 10,000- to 100,000-year astronomical cycles in deep-sea Pleistocene sediments. Milutin Milanković's theory “Earth's climate is regulated by the periodicity of perturbations in the Earth's orbit around the Sun and Earth's axis of rotation,” said Adriana Dutkiewicz, a researcher at the University of Sydney, and colleagues.

“Apart from the well-known astronomical cycles of 19,000, 23,000, 41,000, 100,000, and 400,000 years, which vary according to the Earth's climate, the geological record includes Large-period signals with longer periods are also included.”

“These large cycles contain orbitally forced periodicities of millions or even tens of millions of years, which are similarly related to incoming solar energy and paleoclimate changes. I am.”

In a new study, the authors used deep-sea sediment records to confirm the link between sediment movement and changes in Earth's orbit.

They discovered that the strength of deep ocean currents changes over a 2.4 million year cycle.

“We were surprised to find these 2.4 million-year cycles in deep-sea sediment data,” Dr. Dutkiewicz said.

“There's only one way to explain them. They're related to the cycle of Mars-Earth interactions around the sun.”

“The gravitational fields of the planets in our solar system interfere with each other, and this interaction, called resonance, changes the planet's eccentricity, a measure of how circular a planet's orbit is.”

“For Earth, that means a 2.4-million-year period of increased solar radiation and a warming climate.”

The researchers found that warming cycles are associated with an increase in deep ocean circulation, which correlates with increased breaks in the deep ocean record.

They identified deep eddies as a key component of early ocean warming.

Although these may partially alleviate ocean stagnation, some predict that subsequent stagnation may follow. AMOC (Atlantic meridional overturning circulation) drives the Gulf Stream and maintains Europe's warm climate.

“We now know that there are at least two distinct mechanisms that contribute to the active mixing of deep water in the ocean,” Professor Müller said.

“Deep-ocean eddies, of which AMOC is one, appear to play an important role in keeping the ocean ventilated in warmer climates.”

“Of course, it doesn't have the same effect as the AMOC in terms of transporting water masses from lower to higher latitudes and vice versa.”

“These eddies are like giant whirlpools that often reach the ocean floor in deep oceans, resulting in seafloor erosion and the accumulation of large sediments called contours that resemble snowdrifts.”

“Our deep-sea data over 65 million years suggests that there is a more active deep circulation in warmer oceans,” Dr. Dutkiewicz said.

“This could prevent ocean stagnation even if the AMOC slows down or stops altogether.”

of study It was published in the magazine nature communications.

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A. Dutkiewicz other. 2024. Deep-sea hibernation records reveal orbital pacing with an orbital eccentricity of 2.4 million grand cycles. Nat Commune 15th, 1998. doi: 10.1038/s41467-024-46171-5

Source: www.sci.news

There May Be Less Oxygen in Europa’s Ocean, the Essential Fuel for Life, Than Previously Believed

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Jupiter’s moon Europa is covered with an icy shell

NASA/JPL-California Institute of Technology

Jupiter’s moon Europa may not be as ripe for life as we think. Beneath the icy shell is an ocean of water, but as we know, the frigid moon may lack the oxygen needed to support life.

On Europa, oxygen is produced when radiation hits the surface and breaks down the water ice there into its constituent parts hydrogen and oxygen. Models of this process suggest that oxygen production rates can range from 5 kilograms per second to more than 1000 kilograms per second.

Jamie Zareh Researchers at Princeton University made the new estimate using data from the Juno spacecraft, which flew just 353 kilometers above Europa’s surface in 2022. They discovered that oxygen is only produced at a rate of about 12 kilograms per second at the Earth’s surface. This corresponds to the lower bound of previous estimates.

“In a sense, the shell is like Europa’s lungs. It’s continually producing oxygen,” Zaray says. “That said, we can’t say what happens after the oxygen is produced at the surface. How much of the oxygen makes it into the ocean remains a question.”

But if less oxygen is produced in the first place, less oxygen will enter European waters. As a result, researchers may be less likely to discover organisms similar to those living on Earth.

One of the next steps is to figure out how much of that oxygen can penetrate through the alien moon’s icy shell. NASA’s European Clipper mission, scheduled to launch in October, should help solve that problem. It is hoped that this will allow researchers to measure the thickness of the ice and determine whether elements and compounds useful for life can pass through it.

topic:

  • satellite/
  • extraterrestrial life form

Source: www.newscientist.com

Paleontologists claim Dinocephalosaurus was a fully aquatic reptile that delivered offspring in the ocean

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Detailed explanations are provided by paleontologists from Germany, China, the United Kingdom, and the United States. Dinocephalosaurus orientalis a remarkable marine reptile from the Middle Triassic of China, based on seven beautifully preserved specimens.

repair of Dinocephalosaurus orientalis It is depicted in a school of large predatory actinopterygian fishes. Saurictis. Image credit: Marlene Donnelly.

Dinocephalosaurus orientalis They lived in what is now China during the Triassic period about 240 million years ago.

This aquatic reptile could reach up to 6 m (20 ft) in length and had an extremely long neck with 32 separate vertebrae.

the animal looked very similar Tanystropheus hydrides another strange marine reptile that lived during the Middle Triassic period of both Europe and China.

“Both reptiles were similar in size and had some common skull features, including a fish-catching type of dentition,” said Dr Nick Fraser, head of natural sciences at the National Museum of Scotland, and colleagues. Stated.

“but, Dinocephalosaurus orientalis It is unique in having more vertebrae in both its neck and torso, giving it a more snake-like appearance. ”

Dinocephalosaurus orientalis. Image credit: National Museums of Scotland.

Dinocephalosaurus orientalis They are strictly marine reptiles and almost certainly gave birth at sea.

The exact function of its extraordinarily long neck is unknown, but it almost certainly helped catch fish, and in one specimen it is preserved in the stomach contents.

Despite superficial similarities, this reptile was not closely related to the famous long-necked plesiosaur, which evolved only about 40 million years later and inspired the Loch Ness Monster myth.

“This discovery allows us, for the first time, to see the entire body of this amazing long-necked animal,” Dr Fraser said.

“This is another example of the weird and wonderful world of the Triassic that continues to baffle paleontologists.”

“With its striking appearance reminiscent of the long, serpentine dragon of Chinese mythology, we are confident it will capture imaginations around the world.”

Dinocephalosaurus orientalis First described in 2003, the discovery of additional, more complete specimens has allowed the authors to fully describe this strange long-necked creature for the first time.

“Among the amazing discoveries we made in the Triassic of Guizhou, Dinocephalosaurus orientalis It probably stands out as the most remarkable,” said Professor Li Chun, a paleontologist at the Institute of Vertebrate Paleontology and Paleoanthropology.

of findings Published in today's magazine Earth and Environmental Sciences: Papers of the Royal Society of Edinburgh.

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Stephen NF Speakman other. Dinocephalosaurus orientalis Li, 2003: A remarkable marine archosaur from the Middle Triassic of southwestern China. Earth and Environmental Sciences: Papers of the Royal Society of Edinburgh, published online on February 23, 2024. doi: 10.1017/S175569102400001X

Source: www.sci.news

Powerful winter storm causes historic California palm tree to fall into ocean

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Refugio State Beach, Calif. — Severe storms that hit California have caused damage in some parts of the state. the most iconic tree.

A majestic palm tree that normally flanks Refugio State Beach just north of Santa Barbara has fallen over the past few days. Images show how a huge 100-year-old tree fell into the sea and was completely uprooted.

Local officials say multiple factors caused the trees to fall. Years of coastal erosion were combined with powerful storm surges and supersaturated soil from a series of atmospheric rivers that brought heavy rain and high winds across the state.

“When the ground becomes saturated, the trees begin to fall, and both eucalyptus and palm trees fall over because the ground becomes too wet for their roots to hold in the ground.” Santa Barbara Craig Vanderswag, chief of the County Fire Battalion, told NBC News.

California State Parks Channel Coast District Superintendent Dena Bellman said officials have tagged several more trees on the coast as at high risk of falling, especially with the new heavy rains hitting California. Ta.

Due to this threat, the park is currently temporarily closed to the public.

The dramatic footage is a symbol of the power of these atmospheric rivers, which climate experts say is growing stronger as the planet's temperature rises.

Los Angeles received 75% of its annual average precipitation in the first three weeks of February alone. The city has received more rainfall than Seattle, New Orleans and Miami, and is about 2 inches away from setting a record for the wettest February.

Source: www.nbcnews.com

A possibly magma-covered super-Earth with the appearance of an ocean

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Diagram of exoplanet K2-18b based on scientific observations

NASA, ESA, CSA, Joseph Olmstead (STScI)

The types of planets thought to be able to support life may actually be covered in hot magma. Previously thought to have oceans of liquid water, the chemistry of these so-called high sea exoplanets may instead indicate oceans of magma.

Oliver Shortle Researchers from the University of Cambridge used observations from the James Webb Space Telescope (JWST) of the exoplanet K2-18b to reach this conclusion. This world is typically Hycean. This is the name given to a planet with a hydrogen-rich atmosphere above a liquid ocean. These planets also tend to be between Earth and Neptune in size, and the chemicals in their atmospheres suggest the presence of liquid water on their surfaces, making them a prime search for extraterrestrial life. It has become a target.

But recent models of K2-18b's climate suggest it may be hotter than previously thought, hot enough to cause oceans of water to boil away long ago. “From a theoretical perspective regarding the situation here on Earth, it's like the ground is moving beneath our feet,” Schotle says.

The researchers investigated how it would affect Earth's atmospheric chemistry if these oceans were made of magma instead of water. This would be consistent with the expected high temperatures. They found this to be consistent with his JWST observations as well as water bodies.

“These two fundamentally different regimes are very similar,” Schotle says. “Detecting habitable conditions for super-Earths and sub-Neptune-sized planets will be more complex than we expected.”

This means that we probably need more detailed data to tell the difference between a potentially habitable world with oceans of water and a world of burning, inhospitable magma. For K2-18b, Schotle said his additional JWST observations over the next few years should resolve this issue. And when it comes to other Heim worlds, we may need to develop new ideas for how to find liquid water.

topic:

  • exoplanet/
  • james webb space telescope

Source: www.newscientist.com

Possible Vast Global Ocean Discovered Beneath Ice on Saturn’s Moon Mimas

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Mimas photographed by NASA's Cassini spacecraft

NASA/JPL-California Institute of Technology/Space Science I

Saturn's moon Mimas appears to have a vast global ocean beneath its icy shell, according to detailed measurements of its orbit. If other icy worlds have similar oceans, the number of planets that can support life could increase.

Mimas is the smallest of Saturn's seven major moons. For a long time, it was thought that most of it was composed of solid ice and rock, but in 2014 astronomers observed that the orbit around Saturn was unexpectedly wobbling, suggesting that this could only be explained by either a rugby ball-shaped nucleus or a liquid ocean.

Many astronomers rejected the ocean explanation, as the friction required to melt the ice would have caused visible marks on Mimas's surface. However, recent simulations suggest that this ocean may exist even without such traces.

Looking for more clues? Valerie Rainey Researchers from France's Paris Observatory analyzed observations of Mimas' orbit by NASA's Cassini spacecraft. They found that the orbit around Saturn has shifted by about 10 kilometers over 13 years.

According to the team's calculations, this orbital drift could only have been caused by an ice shell sliding over the ocean, or by wobbles from the physically impossible pancake-shaped core.

The moon's elliptical orbit and lack of surface markings also suggest that the ocean is about 30 kilometers deep and formed less than 25 million years ago. “It was very recent,” Rainey says. “We are more or less witnessing the birth of this global ocean.”

This recent activity could help explain not only the lack of traces on the surface, but also why the moon is so different from its neighbors. Enceladus has a similar shape and orbit to Mimas, and has a global ocean, but it also has a very active surface and giant spout. Rainey said the difference is simply a difference in time, and in a few million years Mimas' ice could melt and it could look similar to Enceladus.

“It would be surprising if that were true,” he says. William McKinnon at Washington University in St. Louis, Missouri. But he says there are still things that aren't perfectly aligned, such as the vast 80-mile-wide Herschel crater, which was formed by a giant impact. If Mimas' ice shell was truly only tens of kilometers deep, McKinnon said, we would have seen evidence of a distorted crater floor in the impact and aftermath. It's also unlikely, he says, that you'll be able to get a front-row seat at such a short and unique time in Mimas' long history. “I remain a Mimas ocean skeptic,” McKinnon says.

However, if Mimas has a hidden ocean, it suggests that other icy planets and moons in the solar system and elsewhere may have the same, expanding the possibility of life. “It's expanding our vision of what is and isn't a habitable world,” Rainey says. “Mimas teaches us that even a corpse that seems to have no life in it may someday come to life.”

topic:

Source: www.newscientist.com

Discovery of four new species of deep-sea octopus in the Pacific Ocean

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Marine biologist at Schmidt Ocean Institute R/V Falco Two expeditions in 2023 exploring seamounts off Costa Rica's Pacific coast discovered at least four new species of deep-sea octopus.

A newly hatched octopus swims away from its egg near a small rocky outcrop informally known as El Dorado Hill. Image credit: Schmidt Ocean Institute.

“The impact is that R/V Falco Research to understand Costa Rica's deep Pacific Ocean will continue into the future and hopefully generate awareness that will lead to policies that protect the country's deep sea,” said Dr. Jorge Cortés, a researcher at the University of Costa Rica.

“We hope this expedition will inspire new generations. Further international cooperation is needed to increase knowledge about our deep-sea heritage.”

During the first expedition in June 2023, Dr. Cortes and colleagues discovered two octopus farms associated with thermal springs.

Six months later, they returned to the nursery and confirmed that they appear to be active year-round.

They also observed several other new species of octopus away from the hot springs.

One of the new species belongs to the genus Octopus Muusocops The octopus is named after the small rocky outcrop, informally known as El Dorado Hills, where it was first discovered.

This is a different species, closely related to, but a different deep-sea octopus farm, found in California's Davidson Seamount in 2018.

Of the four new species in Costa Rica, only the dorado octopus was observed spawning in hot springs.

This discovery is Muusocops This genus evolved to raise its eggs in warm springs on the ocean floor.

“After hard work, our team has discovered a new hydrothermal spring off the coast of Costa Rica, which has become a nursery for deep-sea octopuses and a unique biodiversity site,” said Dr. Beth Orcutt, a researcher at the Bigelow Institute of Marine Science. We confirmed that this is the habitat.”

“It was less than 10 years ago that low-temperature hydrothermal eruptions were detected in ancient volcanoes located far from mid-ocean ridges.”

“These locations are very difficult to find because you can't detect any trace of it in the water column.”

Researchers also discovered a thriving deep-sea skating nursery on the top of another seamount in Costa Rican waters, which they named Skatepark.

They also discovered three hydrothermal springs within the region, located 10 to 30 nautical miles from each other.

These springs all differ from each other in the temperature and chemistry of their fluids, indicating that unique reaction processes drive their formation.

“The Schmidt Ocean Institute supports the global scientific community wherever it is located. Falcor ” said Dr. Jyothika Virmani, Executive Director. Schmidt Ocean Institute.

“Dr. Cortés and Dr. Orcutt have assembled a team that truly embodies international collaboration that empowers Costa Rica's domestic scientists and enriches local knowledge and understanding of the ocean.”

“We look forward to operating off the coasts of Peru and Chile in 2024 and welcoming scientists from South America.”

Source: www.sci.news

High-profile ocean models accelerated by custom software

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This figure shows surface currents simulated by MPAS-Ocean.Credit: Los Alamos National Laboratory, E3SM, U.S. Department of Energy

A new solver algorithm for the MPAS-Ocean model will significantly enhance climate research by reducing and improving computational time. Accuracy. This breakthrough in integrating Fortran and C++ programming is a step forward in efficient and reliable climate modeling.

On the beach, ocean waves provide soothing white noise. However, in scientific laboratories, they play an important role in weather forecasting and climate research. The ocean, along with the atmosphere, is typically one of the largest and most computationally intensive components of Earth system models, such as the Department of Energy’s Energy Exascale Earth System Model (E3SM).

A breakthrough in ocean modeling

Most modern ocean models focus on two categories of waves: barotropic systems, where the wave propagation speed is fast, and baroclinic systems, where the wave propagation speed is slow. To address the challenge of simulating these two modes simultaneously, a team from DOE’s Oak Ridge National Laboratory, Los Alamos National Laboratory, and Sandia National Laboratories has We have developed a new solver algorithm to shorten it. -Ocean, E3SM ocean circulation model, increased by 45%.

The researchers tested the software on the Summit supercomputer at ORNL’s Oak Ridge Leadership Computing Facility, a DOE Office of Science user facility, and the Compy supercomputer at Pacific Northwest National Laboratory. They ran the main simulations on the Cori and Perlmutter supercomputers at the National Energy Research Scientific Computing Center at Lawrence Berkeley National Laboratory, and their results were International Journal of High Performance Computing Applicationss.

Computing innovations for climate modeling

because TrilinosBecause open source software databases ideal for solving scientific problems on supercomputers are written in the C++ programming language, and Earth system models like E3SM are typically written in Fortran, the team took advantage of the advantages of For Trilinois an associated software library that incorporates Fortran interfaces into existing C++ packages to design and customize new solvers focused on barotropic waves.

“A nice feature of this interface is that you can use all the components of the C++ package in the Fortran language, so you don’t have to translate anything, which is very convenient,” said lead author Hyun, a computational earth systems scientist. Kang said. ORNL.

Improvements to MPAS-Ocean

This work is built on Research results announced before Journal of Advances in Earth System Modeling In this paper, researchers at ORNL and Los Alamos National Laboratory handcrafted code to improve MPAS-Ocean. This time, the ForTrilinos-enabled solver overcomes the remaining shortcomings of the solver obtained in previous studies, especially when the user runs his MPAS-Ocean using a small number of computing cores for a given problem size. Did.

MPAS-Ocean’s default solver is an explicit sub-solver, a technique that uses a large number of small time intervals or time steps to compute barotropic wave properties in conjunction with baroclinic calculations without destabilizing the model. Cycle dependent. If the barotropic and barotropic waves can be advanced with time step sizes of 300 and 15 seconds, respectively, then to maintain the same speed the barotropic calculation would need to complete over 20 times more iterations, a huge amount requires computational power.

In contrast, the new solver for barotropic systems is semi-implicit. That is, it is unconditionally stable, allowing researchers to use the same number of large time steps without sacrificing accuracy, saving significant time and computational power.

The community of software developers has spent years optimizing Trillinos and Fort Lilinos’ various climate applications. As such, a modern MPAS-Ocean solver that leverages this resource will outperform hand-crafted solvers and enable other scientists to accelerate their climate research efforts.

“If we had to code every algorithm individually, it would require much more effort and expertise,” Kang said. “But with this software, you can run simulations quickly and quickly by incorporating optimized algorithms into your programs.”

Future enhancements and impact

Current solvers still have scalability limitations for high-performance computing systems, but they perform very well up to a certain number of processors. This drawback exists because the semi-implicit method requires all processors to communicate with each other at least 10 times per time step, which can reduce model performance. To overcome this obstacle, researchers are currently optimizing processor communication and porting solvers to GPUs.

In addition, the team updated the time-stepping method of the pressure clinic system to further improve the efficiency of MPAS-Ocean. Through these advances, researchers are making climate predictions faster and more reliable, an essential upgrade to ensure climate security and enable timely decision-making and high-resolution forecasting, aims to be more accurate.

“This barotropic mode solver enables faster calculations and more stable integration of models, especially for MPAS-Ocean,” said Kang. “Extensive use of computational resources requires enormous amounts of power and energy, but by accelerating this model we can reduce energy usage, improve simulations, and improve performance over decades and even beyond.” It will be easier to predict the effects of climate change thousands of years into the future.”

Reference: “MPAS-ocean implicit pressure mode solver using a modern Fortran solver interface” by Hyun-Gyu Kang, Raymond S Tuminaro, Andrey Prokopenko, Seth R Johnson, Andrew G Salinger, Katherine J Evans, 2023. November 17th, International Journal of High Performance Computing Applications.
DOI: 10.1177/10943420231205601

This research was supported by E3SM and the Exascale Computing Project (ECP). E3SM is sponsored by the DOE Office of Science’s Biological and Environmental Research Program, and ECP is managed by DOE and the National Nuclear Security Administration. The DOE Office of Science’s Advanced Scientific Computing Research Program funds OLCF and NERSC.

Source: scitechdaily.com

Proxima B’s Explosive Cryovolcano and Habitable Subsurface Ocean

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Astronomers at NASA and the University of Washington estimated the total internal heating rate and depth to potential subsurface oceans for 17 potentially cold ocean planets. These planets are low-mass exoplanets with surface temperatures and densities consistent with icy surfaces and large amounts of water. content. Like the icy moons of our solar system, these planets could be astrobiologically important worlds with habitable environments beneath their icy surfaces.

This artist’s impression shows Proxima b orbiting Proxima Centauri, the closest star to our solar system at just 4.23 light years. The double star Alpha Centauri AB also appears in the image between the exoplanet and Proxima itself. Image credit: M. Kornmesser / ESO.

Ocean planets have been proposed as a class of low-density terrestrial exoplanets with significant liquid water layers.

They exist in different climatic states, including ice-free, partially ice-covered, and completely frozen surfaces.

“Our analysis suggests that the surfaces of these 17 alien worlds may be covered in ice, but they are affected by internal heating due to the decay of radioactive elements and tidal forces from their host stars,” said NASA Goddard researcher Dr. Lynne Quick. “We predict that it will receive enough water to maintain its internal ocean.” Space flight center.

“Due to the amount of internal heating the planets experience, all the planets in our study may also exhibit polar volcanic eruptions in the form of geyser-like plumes.”

Dr. Quick and his colleagues examined the status of 17 confirmed exoplanets. These planets are roughly Earth-sized but less dense, suggesting they may have significant amounts of ice and water instead of dense rock.

Although the exact composition of these planets remains unknown, all initial estimates of surface temperatures from previous studies indicate that they are much cooler than Earth, and their surfaces may be covered with ice. This suggests that there is a possibility that

The authors improved their estimates of each exoplanet’s surface temperature by recalculating them using the known surface brightness and other properties of Europa and Enceladus as models.

They also estimated the total internal heating of these exoplanets by using the shape of each exoplanet’s orbit to capture the heat generated from the tides and adding it to the heat expected from radioactive activity. did.

Because oceans cool and freeze at the surface while being heated from within, estimates of surface temperature and total heating provide information about the thickness of each exoplanet’s ice layer.

Finally, they compared these numbers to Europa’s and used Europa’s estimated level of geyser activity as a conservative baseline for estimating the exoplanet’s geyser activity.

They predict surface temperatures will be up to 33 degrees Celsius (60 degrees Fahrenheit) cooler than previous estimates.

Artist’s impression of the planetary system LHS 1140. Image credit: Sci.News.

Estimated ice shell thicknesses ranged from approximately 58 m (190 ft) for Proxima b and 1.6 km (1 mi) for LHS 1140b to 38.6 km (24 mi) for LHS 1140b. MOA-2007-BLG-192Lbcompared to an estimated European average of 29 km (18 mi).

The estimated geyser activity was only 8 kg/s for Kepler 441b, 2,000 kg/s for Europa, 290,000 kg/s for LHS 1140b, and 6 million kg/s for Proxima b.

“Our models predict that oceans could be found relatively close to the surfaces of Proxima b and LHS 1140b, and that geyser activity rates could exceed those of Europa by hundreds to thousands of times. “The telescope has the best chance of detecting geological activity on these planets because of their presence,” said Dr. Quick.

“This activity can be seen when an exoplanet passes in front of its star. Certain colors of the star’s light can be dimmed or blocked by water vapor from geysers. there is.”

“If water vapor is detected sporadically and the amount of water vapor detected changes over time, it would suggest the presence of a cryovolcanic eruption.”

“Water may contain other elements and compounds, which could reveal whether it can support life.”

“Elements and compounds absorb light of certain characteristic colors, so analysis of starlight allows scientists to determine the composition of geysers and assess the potential habitability of exoplanets. Become.”

a paper Regarding the survey results, astrophysical journal.

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Lynne C. Quick other. 2023. Prospects for polar volcanic activity on cold ocean planets. APJ 956, 29; doi: 10.3847/1538-4357/ace9b6

Source: www.sci.news

Potential presence of cyanide in the ocean of Saturn’s moon Enceladus could aid in sustaining life

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Illustration of NASA’s Cassini spacecraft diving through the plume of Saturn’s moon Enceladus.

NASA/JPL-California Institute of Technology

The plumes of water vapor spewing from Enceladus’ surface appear to contain hydrogen cyanide, which, perhaps counterintuitively, suggests that there may be life in the oceans beneath the surface of this icy moon of Saturn. It shows that it is possible.

The Cassini spacecraft flew through Enceladus’ plume several times in the early 2000s, capturing samples as it hurtled past. Preliminary analyzes of these samples have revealed several elements and compounds that may be important for life, but many are not, as the molecules tend to fracture after impacting Cassini’s sampling chamber at high speeds. It has been difficult to identify specific compounds.

Jonah Peter Researchers at Harvard University performed a reanalysis of the Cassini data using new statistical methods and were able to extract more compounds present in the plume. They found evidence of several previously undetected compounds, including hydrogen cyanide, acetylene, ethane, and even trace amounts of the alcohol methanol.

All of these compounds could be part of chemical reactions important to life, but hydrogen cyanide is particularly promising.

“We still don’t have a complete picture of the molecules that are there and are necessary for the origin of life. We don’t even know how the origin of life occurred on Earth,” Peter said. say. “But we know a lot about some of the building blocks that are necessary for the beginning of life, and hydrogen cyanide is one of those very versatile building blocks.”

We know that it can be a building block for amino acids, RNA, and other large biomolecules, so its presence in the plume points to the possibility of life in Enceladus’ subsurface ocean. That’s a good sign.

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Source: www.newscientist.com