Thursday, January 27, 2022

COVID hits one of the last uninfected places on the planet

By NICK PERRY and SAM METZ

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 In this March 30, 2004, file photo, Tarawa atoll, Kiribati, is seen in an aerial view. Kiribati and several other small Pacific nations were among the last on the planet to have avoided any virus outbreaks, thanks to their remote locations and strict border controls. But their defenses appear no match against the highly contagious omicron variant. (AP Photo/Richard Vogel, File)

WELLINGTON, New Zealand (AP) — When the coronavirus began spreading around the world, the remote Pacific archipelago of Kiribati closed its borders, ensuring the disease didn’t reach its shores for nearly two full years.

Kiribati finally began reopening this month, allowing the Church of Jesus Christ of Latter-day Saints to charter a plane to bring home 54 of the island nation’s citizens. Many of those aboard were missionaries who had left Kiribati before the border closure to spread the faith abroad for what is commonly known as the Mormon church.

Officials tested each returning passenger three times in nearby Fiji, required that they be vaccinated, and put them in quarantine with additional testing when they arrived home.

It wasn’t enough.

More than half the passengers tested positive for the virus, which has now slipped out into the community and prompted the government to declare a state of disaster. An initial 36 positive cases from the flight had ballooned to 181 cases by Friday.

Kiribati and several other small Pacific nations were among the last places on the planet to have avoided any virus outbreaks, thanks to their remote locations and strict border controls. But their defenses appear no match against the highly contagious omicron variant.

“Generally speaking, it’s inevitable. It will get to every corner of the world,” said Helen Petousis-Harris, a vaccine expert at the University of Auckland in New Zealand. “It’s a matter of buying enough time to prepare and getting as many people vaccinated as possible.”

Only 33% of Kiribati’s 113,000 people are fully vaccinated, while 59% have had at least one dose, according to the online scientific publication Our World in Data. And like many other Pacific nations, Kiribati offers only basic health services.

Dr. Api Talemaitoga, who chairs a network of Indigenous Pacific Island doctors in New Zealand, said Kiribati had only a couple of intensive care beds in the entire nation, and in the past relied on sending its sickest patients to Fiji or New Zealand for treatment.

He said that given the limitations of Kiribati’s health system, his first reaction when he heard about the outbreak was, “Oh, my lord.”

Kiribati has now opened multiple quarantine sites, declared a curfew and imposed lockdowns. President Taneti Maamau said on social media that the government is using all its resources to manage the situation, and urged people to get vaccinated.

The Church of Jesus Christ of Latter-day Saints, based in the U.S. state of Utah, has a strong presence in many Pacific nations, including Kiribati, where its 20,000 members make it the third-largest Christian denomination. The church has about 53,000 missionaries serving full time around the world, working to convert people.

The pandemic has presented challenges for their missionary work, which is considered a rite of passage for men as young as 18 and women as young as 19.

As the pandemic ebbed and flowed, the church responded. It recalled about 26,000 missionaries who were serving overseas in June 2020, reassigning them to proselytize online from home before sending some back out into the field five months later.

When COVID-19 vaccines became widely available in many countries in April 2021, church officials encouraged all missionaries to get inoculated and required it of those serving outside their home countries.

Church spokesperson Sam Penrod said the returning missionaries remained in quarantine, were cooperating with local health authorities and would be released from their service upon completion of their quarantine.

“With Kiribati’s borders being closed since the onset of the pandemic, many of these individuals have continued as missionaries well beyond their 18 to 24 months of anticipated service, with some serving as long as 44 months,” he said.

Before this month’s outbreak, Kiribati had reported just two virus cases: crew members on an incoming cargo ship that ultimately wasn’t permitted to dock.

But the Kiribati charter flight wasn’t the first time missionaries returning home to a Pacific island nation tested positive for COVID-19.

In October, a missionary returning to Tonga from service in Africa was reported as the country’s first — and so far only — positive case after flying home via New Zealand. Like those returning to Kiribati, he also was vaccinated and quarantined.

Tonga is desperately trying to prevent any outbreaks as it recovers from a devastating volcanic eruption and tsunami earlier this month. The nation of 105,000 has been receiving aid from around the world but has requested that crews from incoming military ships and planes drop their supplies and leave without having any contact with those on the ground.

“They’ve got enough on their hands without compounding it with the spread of COVID,” said Petousis-Harris, the vaccine expert. “Anything they can do to keep it out is going to be important. COVID would be just compounding that disaster.”

In the long term, however, it is going to be impossible to stop the virus from entering Tonga or any other community, Petousis-Harris said.

Nearby Samoa, with a population of 205,000, is also trying to prevent its first outbreak. It imposed a lockdown through until Friday evening after 15 passengers on an incoming flight from Australia last week tested positive.

By Thursday, that number had grown to 27, including five front-line nurses who had treated the passengers. Officials said all those infected had been isolated and there was no community outbreak so far.

While the incursion of the virus into the Pacific has prompted lockdowns and other restrictions, there were signs that not all traditional aspects of island life would be lost for long.

“Government has decided to allow fishing,” Kiribati declared on Thursday, while listing certain restrictions on times and places. “Only four people will be allowed to be on a boat or part of a group fishing near shore.”

___

Metz reported from Salt Lake City.
Toyota heading to moon with cruiser, robotic arms, dreams

By YURI KAGEYAMA

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This graphic illustration provided by Toyota Motor Corp. shows a vehicle called "Lunar Cruiser" to explore the lunar surface. Toyota is working with Japan's space agency on the Lunar Cruiser to explore the lunar surface, with ambitions to help people live on the moon by 2040 and then go live on Mars, company officials said Friday, Jan. 28, 2022. (Toyota Motor Corp. via AP)


TOKYO (AP) — Toyota is working with Japan’s space agency on a vehicle to explore the lunar surface, with ambitions to help people live on the moon by 2040 and then go live on Mars, company officials said Friday.

The vehicle being developed with the Japan Aerospace Exploration Agency is called Lunar Cruiser, whose name pays homage to the Toyota Land Cruiser sport utility vehicle. Its launch is set for the late 2020’s.

The vehicle is based on the idea that people eat, work, sleep and communicate with others safely in cars, and the same can be done in outer space, said Takao Sato, who heads the Lunar Cruiser project at Toyota Motor Corp.

“We see space as an area for our once-in-a-century transformation. By going to space, we may be able to develop telecommunications and other technology that will prove valuable to human life,” Sato told The Associated Press.

Gitai Japan Inc., a venture contracted with Toyota, has developed a robotic arm for the Lunar Cruiser, designed to perform tasks such as inspection and maintenance. Its “grapple fixture” allows the arm’s end to be changed so it can work like different tools, scooping, lifting and sweeping.

Gitai Chief Executive Sho Nakanose said he felt the challenge of blasting off into space has basically been met but working in space entails big costs and hazards for astronauts. That’s where robots would come in handy, he said.

Since its founding in the 1930s, Toyota has fretted about losing a core business because of changing times. It has ventured into housing, boats, jets and robots. Its net-connected sustainable living quarters near Mount Fuji, called Woven City, where construction is starting this year.

Japanese fascination with the moon has been growing.

A private Japanese venture called ispace Inc. is working on lunar rovers, landing and orbiting, and is scheduled for a moon landing later this year. Businessman Yusaku Maezawa, who recently took videos of himself floating around in the International Space Station, has booked an orbit around the moon aboard Tesla CEO Elon Musk’s Starship.

Toyota engineer Shinichiro Noda said he is excited about the lunar project, an extension of the automaker’s longtime mission to serve customers and the moon may provide valuable resources for life on Earth.

“Sending our cars to the moon is our mission,” he said. Toyota has vehicles almost everywhere. “But this is about taking our cars to somewhere we have never been.”

___

Yuri Kageyama is on Twitter https://twitter.com/yurikageyama
GOING GREEN
Tesla-beating battery discovery could finally give us QUIET electric planes – reducing both noise and CO2 pollution



Charlotte Edwards
Technology and Science Reporter
26 Jan 2022


A BATTERY breakthrough could lead to electric planes that produce significantly less pollution and noise.

Researchers in Japan have created a world-leading battery that achieves more than double the density of Tesla batteries.

1The electric planes that exist right now are tiny because we don't have electric batteries that are light but powerful enough to provide energy for long-distance air travelCredit: AFP

This means the battery can stay small but provide a lot of power.

It could be a breakthrough for electric planes as the battery would be light enough to let the aircraft fly while still providing enough energy for long-distance travel.

The NIMS lithium-air battery has an energy density 500Wh/kg.

Elon Musk's Tesla vehicles contain lithium-ion batteries but they have an energy density of 260Wh/kg.

The new battery could also be used in smaller appliances.

It's said to be safe to use in the household because it can be charged and discharged at a normal temperature.

A NIMS release stated that the battery “shows the highest energy densities and best life cycle performance ever achieved”

It also claimed: "Lithium-air batteries have the potential to be the ultimate rechargeable batteries: they are lightweight and high capacity, with theoretical energy densities several times that of currently available lithium-ion batteries."

The researchers will now conduct new experiments on the battery to see if its life cycle can be increased significantly.

Electric planes do exist right now but they're small and can't carry a lot of people over a long distance.

Long haul electric planes could help to significantly reduce greenhouse gas emissions.

They could also make air travel a lot quieter.

Without fuel-burning energy, planes would make less noise.

Right now, a lot of airports have to be built in areas with low populations because of the noise pollution issue.

Aircraft noise is currently a major barrier to airport expansions.

Japanese researchers develop high energy density lithium-air battery

MINING.COM Staff Writer | January 26, 2022 

Electric vehicles charging. (Reference image by Ivan Radic, Flickr).

Researchers at Japan’s National Institute of Materials (NIMS) and Softbank Corp. have developed a lithium-air battery with an energy density of over 500Wh/kg, which is significantly higher than current lithium-ion batteries.


In a paper published in the journal Materials Horizons, the scientific team behind the development explains that this battery can be charged and discharged at room temperature and shows the highest energy densities and best cycle life performances ever achieved.

Lithium-air batteries are metal-air electrochemical cells or battery chemistries that use oxidation of lithium at the anode and reduction of oxygen at the cathode to induce a current flow.

Scientists believe the devices have the potential to be the ultimate rechargeable batteries: they are lightweight and high capacity, with theoretical energy densities several times that of currently available lithium-ion batteries.

Once the technology reaches commercial stage, the batteries could be used in drones, electric vehicles and household electricity storage systems.

Despite their very high theoretical energy densities, only a small number of lithium-air batteries with high energy densities have actually been fabricated and evaluated. This limited success is attributed to the fact that a large proportion by weight of lithium-air battery contains heavy inactive components such as separators and electrolytes that do not directly participate in actual battery reactions.

With the goal of advancing the technology, NIMS and Softbank sought funding from the Japan Science and Technology Agency and in 2018, co-founded the Advanced Technologies Development Center. The ultimate objective is to put lithium-air batteries into practical use in mobile phone base stations, the Internet of Things, high altitude platform stations and other systems.

Thus, they started developing original battery materials that significantly increased the performance of lithium-air batteries. Then, they came up with a technique to fabricate high-energy-density lithium-air cells and finally, the group created a new lithium-air battery by combining these new materials and the fabrication techniques.

The resulting battery exhibited energy density over 500 Wh/kg—substantially higher than currently lithium-ion batteries. Notably, the repeated discharge and charge reaction proceeds at room temperature. The energy density and cycle life performance of this battery are among the highest ever achieved.

To continue building on this success, the team is currently developing higher-performance battery materials and plans to integrate them into the newly created lithium-air battery with the aim of greatly increasing the battery’s cycle life.
Offshore wind farms could help capture carbon from air and store it long-term – using energy that would otherwise go to waste


The U.S. had seven operating offshore wind turbines with 42 megawatts of capacity in 2021. The Biden administration’s goal is 30,000 megawatts by 2030. 

AP Photo/Michael Dw

January 25, 2022

Off the Massachusetts and New York coasts, developers are preparing to build the United States’ first federally approved utility-scale offshore wind farms – 74 turbines in all that could power 470,000 homes. More than a dozen other offshore wind projects are awaiting approval along the Eastern Seaboard.

By 2030, the Biden administration’s goal is to have 30 gigawatts of offshore wind energy flowing, enough to power more than 10 million homes.

Replacing fossil fuel-based energy with clean energy like wind power is essential to holding off the worsening effects of climate change. But that transition isn’t happening fast enough to stop global warming. Human activities have pumped so much carbon dioxide into the atmosphere that we will also have to remove carbon dioxide from the air and lock it away permanently.

Offshore wind farms are uniquely positioned to do both – and save money.

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Most renewable energy lease areas off the Atlantic Coast are near the Mid-Atlantic states and Massachusetts. About 480,000 acres of the New York Bight is scheduled to be auctioned for wind farms in February 2022. BOEM

As a marine geophysicist, I have been exploring the potential for pairing wind turbines with technology that captures carbon dioxide directly from the air and stores it in natural reservoirs under the ocean. Built together, these technologies could reduce the energy costs of carbon capture and minimize the need for onshore pipelines, reducing impacts on the environment.
Capturing CO2 from the air

Several research groups and tech startups are testing direct air capture devices that can pull carbon dioxide directly from the atmosphere. The technology works, but the early projects so far are expensive and energy intensive.

The systems use filters or liquid solutions that capture CO2 from air blown across them. Once the filters are full, electricity and heat are needed to release the carbon dioxide and restart the capture cycle.

For the process to achieve net negative emissions, the energy source must be carbon-free.

The world’s largest active direct air capture plant operating today does this by using waste heat and renewable energy. The plant, in Iceland, then pumps its captured carbon dioxide into the underlying basalt rock, where the CO2 reacts with the basalt and calcifies, turning to solid mineral.

A similar process could be created with offshore wind turbines.

If direct air capture systems were built alongside offshore wind turbines, they would have an immediate source of clean energy from excess wind power and could pipe captured carbon dioxide directly to storage beneath the sea floor below, reducing the need for extensive pipeline systems.
Climeworks, a Swiss company, has 15 direct air capture plants removing carbon dioxide from the air. Climeworks

Researchers are currently studying how these systems function under marine conditions. Direct air capture is only beginning to be deployed on land, and the technology likely would have to be modified for the harsh ocean environment. But planning should start now so wind power projects are positioned to take advantage of carbon storage sites and designed so the platforms, sub-sea infrastructure and cabled networks can be shared.

Read more: These machines scrub greenhouse gases from the air – an inventor of direct air capture technology shows how it works
Using excess wind power when it isn’t needed

By nature, wind energy is intermittent. Demand for energy also varies. When the wind can produce more power than is needed, production is curtailed and electricity that could be used is lost.

That unused power could instead be used to remove carbon from the air and lock it away.

For example, New York State’s goal is to have 9 gigawatts of offshore wind power by 2035. Those 9 gigawatts would be expected to deliver 27.5 terawatt-hours of electricity per year.

Based on historical wind curtailment rates in the U.S., a surplus of 825 megawatt-hours of electrical energy per year may be expected as offshore wind farms expand to meet this goal. Assuming direct air capture’s efficiency continues to improve and reaches commercial targets, this surplus energy could be used to capture and store upwards of 0.5 million tons of CO2 per year.

That’s if the system only used surplus energy that would have gone to waste. If it used more wind power, its carbon capture and storage potential would increase.
Several Mid-Atlantic areas being leased for offshore wind farms also have potential for carbon storage beneath the seafloor. The capacity is measured in millions of metric tons of CO2 per square kilometer. The U.S. produces about 4.5 billion metric tons of CO2 from energy per year. U.S. Department of Energy and Battelle

The Intergovernmental Panel on Climate Change has projected that 100 to 1,000 gigatons of carbon dioxide will have to be removed from the atmosphere over the century to keep global warming under 1.5 degrees Celsius (2.7 Fahrenheit) compared to pre-industrial levels.

Researchers have estimated that sub-seafloor geological formations adjacent to the offshore wind developments planned on the U.S. East Coast have the capacity to store more than 500 gigatons of CO2. Basalt rocks are likely to exist in a string of buried basins across this area too, adding even more storage capacity and enabling CO2 to react with the basalt and solidify over time, though geotechnical surveys have not yet tested these deposits.
Planning both at once saves time and cost

New wind farms built with direct air capture could deliver renewable power to the grid and provide surplus power for carbon capture and storage, optimizing this massive investment for a direct climate benefit.

But it will require planning that starts well in advance of construction. Launching the marine geophysical surveys, environmental monitoring requirements and approval processes for both wind power and storage together can save time, avoid conflicts and improve environmental stewardship.


Author
David Goldberg
Lamont Research Professor, Columbia University
Disclosure statement
David Goldberg receives funding from the US National Science Foundation; Climateworks Foundation, US Dept of Energy, and the Pacific Institute for Climate Solutions
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Wild New Paper Suggests Earth's Tectonic Activity Has an Unseen Source

26 JANUARY 2022

Earth is far from a solid mass of rock. The outer layer of our planet – known as the lithosphere – is made up of more than 20 tectonic plates; as these gargantuan slates glide about the face of the planet, we get the movement of continents, and interaction at the boundaries, not least of which is the rise and fall of entire mountain ranges and oceanic trenches.

Yet there's some debate over what causes these giant slabs of rock to move around in the first place.

Amongst the many hypotheses put forward over the centuries, convection currents generated by the planet's hot core have been discussed as an explanation, but it's doubtful whether this effect would produce enough energy.

A newly published study looks to the skies for an explanation. Noting that force rather than heat is most commonly used to move large objects, the authors suggest that the interplay of gravitational forces from the Sun, Moon, and Earth could be responsible for the movement of Earth's tectonic plates.

Key to the hypothesis is the barycenter – the center of mass of an orbiting system of bodies, in this case that of Earth and the Moon. This is the point around which our Moon actually orbits, and it's not directly in the center of mass of our planet, which we call the geocenter.

Instead, the location of the barycenter within Earth changes over the course of the month by as much as 600 kilometers (373 miles) because the Moon's orbit around Earth is elliptical due to our Sun's gravitational pull.

"Because the oscillating barycenter lies around 4,600 kilometers [2,858 miles] from the geocenter, Earth's tangential orbital acceleration and solar pull are imbalanced except at the barycenter," says geophysicist Anne Hofmeister, from Washington University in St. Louis.

"The planet's warm, thick and strong interior layers can withstand these stresses, but its thin, cold, brittle lithosphere responds by fracturing."

Further strain is added as Earth spins on its axis, flattening out slightly from a perfect spherical shape – and these three stresses from the Moon, Sun, and Earth itself combine to cause the shifting and the splitting of tectonic plates.

"Differences in the alignment and magnitude of the centrifugal force accompanying the solar pull as Earth undulates in its complex orbit about the Sun superimpose highly asymmetric, temporally variable forces on Earth, which is already stressed by spin," the researchers write.

What's happening underneath the surface is that the solid lithosphere and the solid upper mantle are being spun at different speeds because of these stresses and strains, the researchers report – all due to our particular Earth-Moon-Sun configuration.

"Our uniquely large Moon and particular distance from the Sun are essential," says Hofmeister.

Without the Moon, and the shifts it causes between the barycenter and the geocenter, we wouldn't see the tectonic plate activity we get on Earth's surface, the researchers argue. As the Sun's gravitational pull on the Moon is 2.2 times greater than Earth's pull, it will get drawn away from our planet over the next billion years or so.

That said, the gravitational forces at play still need Earth's hot interior for all this to work, the researchers argue.

"We propose that plate tectonics result from two different, but interacting, gravitational processes," they write. "We emphasize that Earth's interior heat is essential to creating the thermal and physical boundary layer known as the lithosphere, its basal melt, and the underlying low-velocity zone."

To further validate the hypothesis outlined in their study, the researchers apply their analysis to several rocky planets and moons in the Solar System, none of which have had confirmed tectonic activity to date. 

Their comparison between Earth and the other major celestial bodies in the Solar System reveals a potential explanation for why we haven't detected tectonic activity on any of the major moons or rocky planets so far. The one closest to Earth in all the necessary parameters, however, is Pluto.

"One test would be a detailed examination of the tectonics of Pluto, which is too small and cold to convect, but has a giant moon and a surprisingly young surface," says Hofmeister.

The research has been published in GSA Special Papers.

Island Obliterated: Dramatic Changes at Hunga Tonga-Hunga Ha’apai

Hunga Tonga-Hunga Ha‘apai 2021

April 10, 2021

NASA scientists have been closely watching the evolution of the volcanic island near Tonga since 2015.

When a volcano in the South Pacific Kingdom of Tonga began erupting in late-December 2021 and then violently exploded in mid-January 2022, NASA scientist Jim Garvin and colleagues were unusually well positioned to study the events. Ever since new land rose above the water surface in 2015 and joined two existing islands, Garvin and an international team of researchers have been monitoring changes there. The team used a combination of satellite observations and surface-based geophysical surveys to track the evolution of the rapidly changing piece of Earth.

The digital elevation maps above and below show the dramatic changes at Hunga Tonga-Hunga Ha‘apai, the uppermost part of a large underwater volcano. It rises 1.8 kilometers (1.1 miles) from the seafloor, stretches 20 kilometers (12 miles) across, and is topped by a submarine caldera 5 kilometers in diameter. The island is part of the rim of the Hunga Caldera and was the only part of the edifice that stood above water.

Now all of the new land is gone, along with large chunks of the two older islands.

Hunga Tonga-Hunga Ha‘apai 2022

January 17, 2022

“This is a preliminary estimate, but we think the amount of energy released by the eruption was equivalent to somewhere between 4 to 18 megatons of TNT,” said Garvin, chief scientist at NASA’s Goddard Space Flight Center. “That number is based on how much was removed, how resistant the rock was, and how high the eruption cloud was blown into the atmosphere at a range of velocities.” The blast released hundreds of times the equivalent mechanical energy of the Hiroshima nuclear explosion. For comparison, scientists estimate Mount St. Helens exploded in 1980 with 24 megatons and Krakatoa burst in 1883 with 200 megatons of energy.

Garvin and NASA colleague Dan Slayback worked with several researchers to develop detailed maps of Hunga Tonga-Hunga Ha‘apai above and below the water line. They used high-resolution radar from the Canadian Space Agency’s RADARSAT Constellation Mission, optical observations from the commercial satellite company Maxar, and altimetry from NASA’s ICESat-2 mission. They also used sonar-based bathymetry data collected by the Schmidt Ocean Institute, in partnership with NASA and Columbia University.

For the past six years, researchers from NASA, Columbia, the Tongan Geological Service, and the Sea Education Association worked together to determine how the young terrain was eroding due to the ongoing churn of waves and occasional battering by tropical cyclones. They also noted how wildlife—various types of shrubs, grasses, insects, and birds—had moved from the lush ecosystems of Hunga Tonga and Hunga Ha‘apai and colonized the more barren landscapes of the newer land.

Hunga Tonga-Hunga Ha‘apai 2019

October 11, 2019

Things changed dramatically in January. For the first few weeks of 2022, the volcanic activity seemed typical enough, with intermittent, small explosions of tephra, ash, steam, and other volcanic gases as magma and seawater interacted at a vent near the middle of the island. The ongoing Surtseyan eruptions were reshaping the landscape and enlarging the island by adding new deposits of ash and tuff to the growing volcanic cone.

“By early January, our data showed the island had expanded by about 60 percent compared to before the December activity started,” said Garvin. “The whole island had been completely covered by a tenth of cubic kilometer of new ash. All of this was pretty normal, expected behavior, and very exciting to our team.”

But on January 13-14, an unusually powerful set of blasts sent ash surging into the stratosphere. Then explosions on January 15 launched material as high as 40 kilometers (25 miles) in altitude and possibly as high as 50 kilometers, blanketing nearby islands with ash and triggering destructive tsunami waves. An astronaut aboard the International Space Station took this photo of ash over the South Pacific.

Ash Over South Pacific January 2022

January 16, 2022

Most Surtseyan style eruptions involve a relatively small amount of water coming into contact with magma. “If there’s just a little water trickling into the magma, it’s like water hitting a hot frying pan. You get a flash of steam and the water burns burn off quickly,” explained Garvin. “What happened on the 15th was really different. We don’t know why — because we don’t have any seismometers on Hunga Tonga-Hunga Ha‘apai — but something must have weakened the hard rock in the foundation and caused a partial collapse of the caldera’s northern rim. Think of that as the bottom of the pan dropping out, allowing huge amounts of water to rush into an underground magma chamber at very high temperature.”

The temperature or magma usually exceeds 1000 degrees Celsius; seawater is closer to 20°C. The mixing of the two can be incredibly explosive, particularly in the confined space of a magma chamber. “This was not your standard Surtseyan eruption because of the large amount of water that had to be involved,” said Garvin. “In fact, some of my colleagues in volcanology think this type of event deserves its own designation. For now, we’re unofficially calling it an ‘ultra Surtseyan’ eruption.”

For a geologist like Garvin, watching the birth and evolution of a “Surtseyan island” like this is fascinating, partly because there have not been many other modern examples. Aside from Surtsey—which formed near Iceland in 1963 to 1967 and still exists more than a half-century later—most new Surtseyan islands get eroded away within a few months or years.

What also interests Garvin about these islands is what they may teach us about Mars. “Small volcanic islands, freshly made, evolving rapidly, are windows in the role of surface waters on Mars and how they may have affected similar small volcanic landforms,” he said. “We actually see fields of similar-looking features on Mars in several regions.”

NASA Earth Observatory images by Joshua Stevens, using elevation data courtesy of Dan Slayback/NASA/GSFC. Astronaut photograph ISS066-E-117965 was acquired on January 16, 2022, with a Nikon D5 digital camera using a focal length of 50 millimeters. NASA ground photo by Dan Slayback.

New Research Strengthens Link Between Glaciers and Earth’s Puzzling “Great Unconformity”

Great Unconformity Study Sites Map

Researchers used thermochronometric data from four North American locations to determine the cause of the “Great Unconformity”—a massive loss of rock about 700 million years ago. Credit: Figure by Kalin McDannell

Ice action seems responsible for ancient erosion of rock across the planet.

New research provides further evidence that rocks representing up to a billion years of geological time were carved away by ancient glaciers during the planet’s “Snowball Earth” period, according to a study published in Proceedings of the National Academy of Sciences.

The research presents the latest findings in a debate over what caused the Earth’s “Great Unconformity”— a time gap in the geological record associated with the erosion of rock up to 3 miles thick in areas across the globe.

“The fact that so many places are missing the sedimentary rocks from this time period has been one of the most puzzling features of the rock record,” said C. Brenhin Keller, an assistant professor of earth sciences and senior researcher on the study. “With these results, the pattern is starting to make a lot more sense.”

The massive amount of missing rock that has come to be known as the Great Unconformity was first named in the Grand Canyon in the late 1800s. The conspicuous geological feature is visible where rock layers from distant time periods are sandwiched together, and it is often identified where rocks with fossils sit directly above those that do not contain fossils.

Mica Mine Unconformity

In Colorado’s Ladder Canyon, rocks that differ in age by about a billion years sit together across the Great Unconformity. Credit: C. Brenhin Keller

“This was a fascinating time in Earth’s history,” said Kalin McDannell, a postdoctoral researcher at Dartmouth and the lead author of the paper. “The Great Unconformity sets the stage for the Cambrian explosion of life, which has always been puzzling since it is so abrupt in the fossil record—geological and evolutionary processes are usually gradual.”

For over a century, researchers have sought to explain the cause of the missing geological time.

In the last five years, two opposing theories have come into focus: One explains that the rock was carved away by ancient glaciers during the Snowball Earth period about 700 to 635 million years ago. The other focuses on a series of plate tectonic events over a much longer period during the assembly and breakup of the supercontinent Rodinia from about 1 billion to 550 million years ago.

Research led by Keller in 2019 first proposed that widespread erosion by continental ice sheets during the Cryogenian glacial interval caused the loss of rock. This was based on geochemical proxies that suggested that large amounts of mass erosion matched with the Snowball Earth period.

“The new research verifies and advances the findings in the earlier study,” said Keller. “Here we are providing independent evidence of rock cooling and miles of exhumation in the Cryogenian period across a large area of North America.”

The study relies on a detailed interpretation of thermochronology to make the assessment.

Brenhin Keller and Kalin McDannell

C. Brenhin Keller, assistant professor of earth sciences, left, and Kalin McDannell, a postdoctoral researcher in earth sciences. Credit: Eli Burakian/Dartmouth College

Thermochronology allows researchers to estimate the temperature that mineral crystals experience over time as well as their position in the continental crust given a particular thermal structure. Those histories can provide evidence of when missing rock was removed and when rocks currently exposed at the surface may have been exhumed.

The researchers used multiple measurements from previously published thermochronometric data taken across four North American locations. The areas, known as cratons, are parts of the continent that are chemically and physically stable, and where plate tectonic activity would not have been common during that time.

By running simulations that searched for the time-temperature path the rocks experienced, the research recorded a widespread signal of rapid, high magnitude cooling that is consistent with about 2-3 miles of erosion during Snowball Earth glaciations across the interior of North America.

“While other studies have used thermochronology to question the glacial origin, a global phenomenon like the Great Unconformity requires a global assessment,” said McDannell. “Glaciation is the simplest explanation for erosion across a vast area during the Snowball Earth period since ice sheets were believed to cover most of North America at that time and can be efficient excavators of rock.”

According to the research team, the competing theory that tectonic activity carved out the missing rock was put forth in 2020 when a separate research group questioned whether ancient glaciers were erosive enough to cause the massive loss of rock. While that research also used thermochronology, it applied an alternate technique at only a single tectonically active location and suggested that the erosion occurred prior to Snowball Earth.

“The underlying concept is pretty simple: Something removed a whole lot of rock, resulting in a whole lot of missing time,” said Keller. “Our research demonstrates that only glacial erosion could be responsible at this scale.”

According to the researchers, the new findings also help explain links between the erosion of rock and the emergence of complex organisms about 530 million years ago during the Cambrian explosion. It is believed that erosion during the Snowball Earth period deposited nutrient-rich sediment in the ocean that could have provided a fertile environment for the building blocks of complex life.

The study notes that the two hypotheses of how the rock eroded are not mutually exclusive—it is possible that both tectonics and glaciation contributed to global Earth system disruption during the formation of the Great Unconformity. It appears, however, that only glaciation can explain erosion in the center of the continent, far from the tectonic margins.

“Ultimately with respect to the Great Unconformity, it may be that the generally accepted reconstruction(s) of more concentrated equatorial packing of the Rodinian continents along with the unique environmental conditions of the Neoproterozoic, proved to be a time of geologic serendipity unlike most any other in Earth history,” the research paper says.

According to the team, this is the first research that uses their thermochronology modeling approach to study a period that extends well beyond a billion years. In the future, the team will repeat their work on other continents, where they hope to further test these hypotheses about how the Great Unconformity was created and preserved.

According to the team, resolving differences in the research is critical to understanding early Earth history and the interconnection of climatic, tectonic and biogeochemical processes.

“The fact that there may have been tectonic erosion along the craton margins does not rule out glaciation,” said McDannell. “Unconformities are composite features, and our work suggests Cryogenian erosion was a key contributor, but it is possible that both earlier and later erosion were involved in forming the unconformity surface in different places. A global examination will tell us more.”

Reference: “Thermochronologic constraints on the origin of the Great Unconformity” 25 January 2022, Proceedings of the National Academy of Sciences.
DOI: 10.1073/pnas.2118682119

William Guenthner, from the University of Illinois at Urbana-Champaign; Peter Zeitler from Lehigh University; and David Shuster from the University of California, Berkeley and the Berkeley Geochronology Center served as co-authors of the paper.

Recent algae discovery gives clues to boost biofuel production

Recent algae discovery gives clues to boost biofuel production
A new study from the MSU-DOE Plant Research Laboratory shows how some algae can protect themselves when the oxygen they produce impairs their photosynthetic activity. Researchers in the David Kramer lab started by testing strains (varieties of the same species) for differences in their ability to grow at high oxygen. The researchers then studied both the parents and the offspring to see why they reacted so differently to hyperoxia. The findings from this study give researchers a fuller understanding of not only algal cell biology, but also photosynthesis. Credit: Kara Headley, MSU-DOE Plant Research Laboratory

A new study from the Michigan State University-Department of Energy (DOE) Plant Research Laboratory (PRL) shows how some algae can protect themselves when the oxygen they produce impairs their photosynthetic activity. The discovery also answers a long-standing question about how algae survive when CO2 levels are low.

The findings of this research from the David Kramer lab was recently published in eLife.

In photosynthesis, plants and algae use  to take carbon dioxide (CO2) from the air and synthesize sugars. This process produces oxygen as a byproduct, which earth's animals depend on to breathe. However, oxygen impairs the activity of key photosynthetic reactions. When algae are grown in dense ponds for bioenergy production, this becomes an obstacle.

Algae are used as a crop for biofuels, a renewable energy resource. Growing algae for biofuel production can be sped up by fertilizing the cultures with CO2. However, when algal growth is increased, oxygen output from photosynthesis increases as well, which leads to an accumulation of oxygen in the culture. This exposure to excess oxygen is called hyperoxia.

"The overall goal was to understand how algae respond to hyperoxia, as a first step to making bioenergy strains that are more tolerant to such stresses and thus more productive," said Peter Neofotis, a postdoctoral researcher in the Kramer lab and first author of the paper.

What the researchers found not only shows how algae survive and ways to potentially make more efficient bioenergy crops, but it also answers a decades-long debate in relation to the induction of the Carbon Concentrating Mechanism (CCM) in .

Differing reactions for differing strains

The researchers started by testing strains (varieties of the same species) for differences in their ability to grow at high oxygen. One called CC-1009 was able to grow steadily in these conditions while another, CC-2343, grew slowly and eventually died. When these two strains were mated, they produced offspring that usually behaved like one parent or the other, but sometimes their behavior was more extreme.

The researchers then studied both the parents and the offspring to see why they reacted so differently to hyperoxia. What they found surprised them because it involved a special process in algae needed for growth at low CO2 but was never previously associated with high oxygen.

Algae  respond to low CO2 by activating the Carbon Concentrating Mechanism (CCM). This biological process pumps CO2 into cells and concentrates it around an enzyme so CO2 can be synthesized into sugars for cellular growth. To operate the CCM, the cells also need to make a special structure in the chloroplasts called the pyrenoid that holds the pumped-in CO2. Without the pyrenoid, cells cannot grow at low CO2.

What the team found was the pyrenoid and CCM also allow the cells to grow at high oxygen, even if the CO2 levels are high.

"This was the first indication that the pyrenoid has a dual function!" said David Kramer, Hannah Distinguished Professor in Photo Synthesis and Bioenergetics in the Department of Biochemistry and Molecular Biology and a PRL faculty member. "It not only concentrates CO2 but protects against O2."

Signaling pyrenoid formation

The discovery of the signal for pyrenoid induction followed the researchers' observation that pyrenoids form not only under low CO2, but also hyperoxia. The researchers then asked: What chemical accumulates not only at low CO2, but at high oxygen that could trigger the pyrenoid?

Recent algae discovery gives clues to boost biofuel production
The carbon concentrating mechanism (CCM). Credit: Kara Headley, MSU-DOE Plant Research Laboratory

Hydrogen peroxide, a common antiseptic that is also used in household products, is produced by plants and algae when photosynthesis is malfunctioning. Both low CO2 and high  cause algal photosynthesis to make . The cells likely detect this and make pyrenoids to fix the problem.

"It's been a big mystery as to how the algae know it's time to make the pyrenoid," Kramer said. "Now that we know a signal, we can potentially get the cells to make pyrenoids whenever we want. This could prepare them to work better during biofuel production."

Josh Temple, a Ph.D. student in the Kramer lab and paper co-author, added: "Despite an abundance of research on pyrenoids and the CCM, the mechanisms underlying their interaction still remain quite nebulous."

Applying findings for better crops

Researchers are constantly looking for ways to increase crop production. One idea is to introduce the algal CCM into land crops to improve the efficiency of photosynthesis. The issue is it is difficult to get the pyrenoid to form in plant cells.

"Now that we have an improved sense of the signal for an aspect of the CCM, we have a pathway to better understand the many genes involved in it," Neofotis said. "Such complete understanding is necessary if we ever want to transfer the algae CCM into land crops. Learning more about how the CCM is regulated also could help with efforts to engineer  well suited for the conditions in biofuel facilities."

Knowing what induces the pyrenoid, a question debated for decades that remained unanswered until now, gives researchers a fuller understanding of not only algal cell biology, but also photosynthesis. As food and energy demand continues to increase, the Plant Research Laboratory remains committed to understanding how to optimize this important process.Algae superpowers could provide major boost to food security

More information: Peter Neofotis et al, The induction of pyrenoid synthesis by hyperoxia and its implications for the natural diversity of photosynthetic responses in Chlamydomonas, eLife (2021). DOI: 10.7554/eLife.67565

Journal information: eLife 

Provided by Michigan State University