Cloud mining – In search of Greenland’s rare earths | Europe


MOST PEOPLE sniggered when Donald Trump proposed buying Greenland in 2019, but he had a point. The world’s biggest island has a rich helping of rare-earth minerals, and the superpowers want them.

These 17 elements, ranging from scandium to lutetium, lurk in the depths of the periodic table and turn up in all things electronic. The renewable-energy revolution will also rely on them for power storage and transmission. On the darker side, weapons—including nuclear ones—need them too.

A new open-pit mine at the top of Kuannersuit, a cloud-rimmed mountain near the settlement of Narsaq in the south of the island, may provide a goodly chunk of the rare earths needed to ditch fossil fuels. So believes Greenland Minerals, actually an Australia-based company, which has been angling for the excavation rights for the past decade.

Greenland’s environment ministry has given a tentative go-ahead. A majority of parliamentarians have already declared themselves in favour of digging. In early February the townsfolk of Narsaq will hear representations from the island’s government; though a dependency of Denmark, Greenland enjoys self-government in most areas except defence and foreign relations. A consultation phase is to last, provisionally, until mid-March.

Residents of Narsaq welcome the opportunity to learn more and to have their say. Urani Naamik (“No to Uranium”), a community lobby, has strong support. Nobody wants (mildly) radioactive dust, an inevitable by-product, drifting down to settle on their town and pastures. Many worry about the lake of waste—a sludge of chemicals and discarded rock fragments—that mining would leave on top of the mountain.

But Greenland’s politicians are in a quandary. The country’s two largest parties both want full independence from Denmark, which currently provides half the territory’s annual budget. But they would then need to be self-sustaining. Greenland would depend on fish, tourism, fresh-water sales and minerals. The last is by far the most valuable.

Christian Schultz-Lorentzen, editor of Greenland’s Sermitsiaq newspaper, says a bigger long-term issue is who gets the mine’s spoils. Shenghe, a Chinese conglomerate, is the largest shareholder in Greenland Minerals. The Danish government, in a frenzy of Atlanticism, earlier managed to stop Chinese companies from investing in the expansion of two airports on the island. Will it preserve Greenland’s rare earths for NATO?

For more coverage of climate change, register for The Climate Issue, our fortnightly newsletter, or visit our climate-change hub

This article appeared in the Europe section of the print edition under the headline “Cloud mining”

Reuse this contentThe Trust Project

Thank you for visiting My Local Pages and checking this story regarding European news named “Cloud mining – In search of Greenland’s rare earths | Europe”. This story is brought to you by MyLocalPages as part of our news aggregator services.

#Cloud #mining #search #Greenlands #rare #earths #Europe



Source link

Carbon dioxide feeds plants, but are earth’s plants getting full?


Plants do a lot of work for us, producing the air we breathe, the food we eat, and even some of our medicine. But when it comes to removing carbon dioxide in the atmosphere, we may have been overestimating their ability.

Photosynthesis acts as the lungs of our planet – plants use light and carbon dioxide (CO₂) to make the sugars they need to grow, releasing oxygen in the process. When atmospheric CO₂ concentrations increase, as they have been thanks to humans burning fossil fuels, one might think that plants are enjoying a smorgasbord of food for unlimited growth. But a new study published in Science shows this excess of riches is not as effective as previously thought.

Since CO₂ is the main source of food for plants, increasing levels of it directly stimulate the photosynthetic rate of most plants. This boost in photosynthesis, known as the “CO₂ fertilisation effect”, enhances growth in many of earth’s plant species, with the effects seen most clearly in crops and young trees, and less so in mature forests.

The amount of CO₂ used by photosynthesis and stored in vegetation and soils has grown over the past 50 years, and now absorbs at least a quarter of human emissions in an average year. We’ve been assuming that this benefit will continue to increase as CO₂ concentrations rise, but data collected over a 33-year period show us that might not be true.

Fertilisation is in decline

Estimating the size of the global CO₂-fertilisation effect accurately is no easy task. We have to understand what limits photosynthesis from one region to another, and at every scale from molecules within a leaf through to whole ecosystems.

The big research team behind the new Science study used a combination of data from satellites and on-the-ground observations and models of the carbon cycle. Using this powerful toolkit, they found that the fertilisation effect declined across much of the globe from 1982 to 2015 – a trend that correlates well with observed changes in nutrient concentrations and available soil water.

In many ways, the combination of these different tools helps to paint a more complete picture of how the world’s ecosystems are photosynthesising. The researchers used a collection of long-term measurements from flux towers like the one pictured below which continuously monitor the CO₂ and water used by plants and are dotted across earth’s biomes and provide the best means of measuring photosynthesis at the ecosystem scale.

Flux towers are limited in their measurement range (1 km or so) – but the data these towers collect helps verify the satellite estimates of how much photosynthesis is going on. With satellites and flux towers now providing records since the 1990s (and earlier in some cases), scientists are able to assess long-term trends in global photosynthesis. These can then be compared to “models” – the computer-based simulations predicting plant-environment interactions – as the researchers did in this recent study.

What might the models be missing?

Researchers in the latest study found that the decrease in CO₂ fertilisation was related to the availability of nutrients and water, which the computer simulations might not be accounting for properly. We know that nutrients such as nitrogen and phosphorus are declining) in some areas – which may be unaccounted for. Plants can also acclimate, or change how they grow, when the environment changes.

Just like we can spend less on groceries when food is plentiful, plants invest less nitrogen in photosynthesis when they are grown at high CO₂. When this happens, CO₂ fertilisation is less effective than before. Because some plants have a stronger response than others, the response can be difficult to account for in computer simulations.

For many years, some people have assumed that carbon fertilisation will mitigate climate change by slowing the rate at which CO₂ is increasing in the atmosphere. Although the effect is built into the models used to predict future climates, the argument has become widely misinterpreted by those who believe the world is overreacting to climate change.

But if the new study is right, and we have indeed been overestimating the amount of carbon that plants will pull from the atmosphere in the future, even our most cautious climate projections have likely been optimistic.

Authors: Amanda Cavanagh – Lecturer, University of Essex | Caitlin Moore – Research Fellow, University of Western Australia The Conversation



Source link

Earth’s Biggest Telescopes Reopen After Months of COVID Closures


After more than six months of COVID-related closures, observational astronomy is largely getting back to work.

Many of the world’s biggest telescopes have reopened their domes in recent weeks, returning their gazes to the heavens for the first time since the pandemic forced a global shutdown of observational astronomy in March. Other major telescopes expect to reopen soon. 

This wave of reopenings was buoyed by declining COVID-19 cases in Chile, especially in the Atacama Desert, a region home to many world-class observatories. U.S. officials who manage telescopes in Hawaii and Arizona say they’re also beginning to resume operations, largely thanks to significant changes in their workflows. 

If major observatories continue to come back online — and remain open — it will end an unprecedented dark era in astronomy. After all, even during World War II, America’s observatories kept a close eye on the skies. 

Astronomy in Quarantine 

Earlier this year, an Astronomy magazine analysis showed that over 100 of Earth’s largest telescopes temporarily shuttered their doors closed due to the COVID-19 pandemic. And by late March, observational astronomy had almost completely shutdown. 

The closures reveal a little-realized truth about modern astronomy. Even in 2020, most observatories are not fully automated. 

Telescopes have grown dramatically larger and more complex in recent decades. They’ve also been pushed to more remote locations, farther and farther from civilization’s expanding light pollution. Basic tasks like swapping the instruments and cleaning the mirrors on these behemoths can require a small village of engineers, technicians, observers, medics, cooks, groundskeepers, and more.

In Chile, where many of the world’s biggest observatories are now located, the telescopes are so far away from cities that employees can’t just commute to the mountain each night. They have to live on campus part-time. Even the astronomers using the instruments typically travel to the observatories during their awarded observing nights. 

This reality forced observatories to shut down in the early days of the pandemic. There was no way to abide by social distancing rules and effectively run the telescopes. In interviews back in March, observatory directors said they expected telescopes to be offline for at least three to six months. And that’s largely how the pandemic played out for them.

A number of observatories did manage to change their workflows enough to feel safe reopening during the summer. And in recent weeks, many of the remaining observatories have likewise reopened. 

The only telescopes little impacted were the small, survey telescopes that run robotically, or with minimal support. These scan the skies for transient objects — the field’s term for unexpected and brief astronomical objects and events. 

For example, the Catalina Sky Survey in Arizona never stopped searching for asteroids. And astronomers kept the Las Cumbres Observatory network of robotic telescopes hunting for both supernovae and space rocks. Hopefully, that was enough to avoid any major gaps in the observational record. 

What Was Missed 

Luckily for the field, those survey telescopes didn’t pick up any once-in-a-lifetime objects that would leave astronomers agonizing over what might have been.

“I’m sure we’ve missed a few things,” says John S. Mulchaey, director of the Carnegie Observatories, which runs some of the world’s largest and most historically important telescopes. “But for most of astronomy, you don’t miss that much. For those of us studying galaxies in the distant universe, they’re gonna be there next year. They’re gonna look the same.” 

Mulchaey says he did ponder how tragic it would have been if Betelgeuse went supernova. Early in the year, astronomers were mystified by the behavior of the dying red supergiant star in the constellation Orion. 

“That doesn’t seem likely, but we haven’t had a visible supernova in our galaxy in 400 years or something,” he says.

Early on, astronomers were also worried about their ability to detect potentially dangerous near-Earth asteroids. And new asteroid detections did decline initially, according to Kelly Fast, NASA’s program manager for Near-Earth Object Observations. However, as smaller observatories found ways to reopen, those detections eventually started going back up. 

“Most stuff that would have been done this year can be done next year,” Mulchaey says. “It means it takes an extra year to get to the answer, but that’s not that bad in the scheme of things.”

Telescopes Restart 

In Chile, the past month has seen telescopes restart at observatories across the country, including Las Campanas, Paranal, Cerro Pachon, and Cerro Tololo Inter-American Observatory. Other major instruments like the Atacama Pathfinder Experiment, the Gemini South telescope, and Southern Astrophysical Research Telescope have also resumed their operations. Below is a brief summary of the statuses of other notable observatories.

  • Construction has restarted at the Vera C. Rubin Observatory, formerly known as the Large Synoptic Survey Telescope, a massive, next-generation instrument that will image the entire visible sky every night. 

  • The Atacama Large Millimeter Array in Chile, or ALMA, has begun working toward reopening. Before the shutdown, astronomers used ALMA’s 66 radio telescopes to help discover phosphine gas in the atmosphere in Venus, which could be evidence of alien life. The finding is controversial though, and researchers could be eager for a second look. However, the array is so complex that it could be months before ALMA is fully back online. 

  • Meanwhile, Kitt Peak National Observatory in Arizona, has started working to get its telescopes observing again. A major new project there called the Dark Energy Spectroscopic Instrument saw first light last fall and researchers are eager to get it operational again. Other major telescopes in the United States opened in May and June. The relatively low number of COVID-19 cases in Hawaii also helped instruments like the Gemini North telescope get back to work.

  • In Antarctica, Earth’s only coronavirus-free continent, upgrades to the South Pole Telescope (SPT) have been postponed as fewer people are deploying to the continent. But SPT’s observing schedule has continued uninterrupted. “There has been a very strict protocol, limiting deployments to only essential personnel and with very strict quarantine rules,” says the University of Chicago’s John Kovac.

  • La Silla Observatory in Chile, home to a number of European Southern Observatory instruments, still hasn’t restarted science operations. 

Although not an observational observatory, LIGO, the Laser Interferometer Gravitational-Wave Observatory, was forced to shut down its observing run a month early due to COVID-19. LIGO was planned to be offline for upgrades until 2022, but the pandemic is causing delays that could extend the process even longer. Processing the data from the last observing run is also taking longer than expected. 

“There are delays due to supply chain issues, changes in how vendors work, and teams learning to work in a COVID-safe way,” says LIGO spokesperson Patrick Brady. They likely won’t know until next year whether the pandemic has postponed LIGO’s ability to tune back into gravitational waves again.

Not the Same

Even as major observatories continue to come back online, many won’t be operating at 100 percent for the foreseeable future.

Large telescopes often have their instruments changed multiple times a night as they start new observing runs. But observatory directors say that changing instruments just won’t be possible in many cases now, as they’ve had to learn to work with dramatically reduced staff. Sometimes, they even have to find ways for one person to do tasks that would usually take an entire team.

Astronomers no longer physically travel to the telescopes from during their observing nights, either. And public tours have also been canceled, robbing observatories of vital revenue and access to potential donors. 

Maintenance has also been delayed. Large telescope mirrors often stretch more than a dozen feet across and sit exposed to the outdoors all night long, gathering dust. That means observatories have to regularly clean and recoat their mirrors, or else they’ll gradually lose their light-gathering abilities.

“One aspect that has suffered at the [Hobby-Eberly Telescope] and other large telescopes is that our mirror cleaning and segment re-aluminization are way behind schedule,” says Steven Janowiecki, an astronomer at the McDonald Observatory who serves as the observatory’s science operations manager. “Those processes require people to be in close proximity and have been significantly reduced since March. That will have long term impacts on our light-collecting ability — perhaps 5 to 15 percent — but we’ll still be observing.”

So, although the observational abilities of major telescopes around the world might remain slightly dimmed in the short term, astronomers and engineers are working hard to get Earth’s observatories fully back in the game.



Source link

UN agency laments summer’s ‘deep wound’ to Earth’s ice cover


The United Nations weather agency says this summer will go down for leaving a “deep wound” in the frozen parts of the planet after a heat wave in the Arctic, shrinking sea ice and the collapse of a leading Canadian ice shelf

GENEVA — The United Nations weather agency says this summer will go down for leaving a “deep wound” in the cryosphere — the planet’s frozen parts — amid a heat wave in the Arctic, shrinking sea ice and the collapse of a leading Canadian ice shelf.

The World Meteorological Organization said Tuesday that temperatures in the Arctic are rising twice as fast as the global average, provoking what spokeswoman Clare Nullis called a “vicious circle.”

“The rapid decline of sea ice in turn contributes to more warming, and so the circle goes on and the consequences do not stay in the Arctic,” Nullis said during a regular U.N. briefing in Geneva.

The weather agency said in a statement that many new temperature records have been set in recent months, including in the Russian town of Verkhoyansk. The town, located in Siberia above the Arctic Circle line, reached 38 degrees Celsius (100 F) on June 20.

“What we saw in Siberia this year was exceptionally bad, was exceptionally severe,” Nullis said. She noted a heat wave across the Arctic, r ecord-breaking wildfires in Siberia, nearly record-low sea ice extent, and the collapse of one of the last fully intact Canadian ice shelves.

“The summer of 2020 will leave a deep wound on the cryosphere,” the World Meteorological Organization statement said, pointing to a “worrisome trend” of floods resulting from the outburst of glacier lakes that are becoming “an increased factor of high-risk in many parts of the world.”

In late July, an 81-square-kilometer (30-square-mile) section of Canada’s Milne ice shelf broke off, reducing the total area of the ice shelf by 43%, the weather agency said.

The consequences include the loss of a rare ecosystem, possible acceleration of glaciers sliding into the ocean and contributing to sea level rise, and creation of new “drifting ice islands,” it said.

The WMO is preparing to release on Sept. 9 a report on the impact of climate change on the cryosphere.

———

Follow AP’s climate coverage at https://apnews.com/Climate



Source link

Humans have now consumed the Earth’s natural resources for the year


It”s called “Overshoot Day”, the moment each year when we humans have used up more natural resources that the Earth can renew in 12 months.

And this year that day came on Saturday, August 22nd.

Put another way, it would take 1.6 Earths this year to meet the needs of the world’s population in a sustainable way.

The calculations were made by American NGO Global Footprint Network — since 2003 it’s been raising the alarm on the ever faster consumption of an expanding human population on a limited planet.

On the one hand there is our ecological footprint, which includes the spewing out of greenhouse gases — then there is the capacity of the earth’s ecosystems to absorb our waste products and renew ones we have consumed, such as wood from cut down trees in forests.

The worrying part is that overshoot day has been falling earlier and earlier every year.

Global Footprint Network estimates it was December 29th in 1970, November 4th in 1980, October 11th in 1990, September 23rd in 2000 and August 7th in 2010.

This year has been an anomaly because the coronavirus pandemic slowed down human activity, delaying the grim milestone slightly compared to last year.

In 2019 Overshoot Day actually fell on July 29th.

The 2015 Paris climate deal saw nations commit to limit temperature rises to “well below” two degrees Celsius (3.6 Fahrenheit) above pre-industrial levels through sweeping emissions cuts.

It also set a safer goal of a 1.5 C cap.

The United Nations says global emissions must fall 7.6 percent annually this decade for that number to be possible.



Source link

A supernova may have killed the monstrous fish of Earth’s Devonian Period


TORONTO —
More than 350 million years ago, Earth was ruled by fish, some up to 10 metres long.

But a mass extinction stretching across millions of years killed up to 80 per cent of all species that existed at that time, bringing an end to the Devonian Period.

Scientists have come up with numerous theories over the years for why this extinction might have occurred, such as volcanic activity, meteorites or rapid global warming.

Now, new research is bringing a new possibility to the forefront: what if a supernova was responsible?

A paper published Tuesday in the Proceedings of the National Academy of Sciences of the United States of America (PNAS) details the brand new theory, and how it could feasibly be proven — or ruled out.

The Devonian Period occurred from roughly 416 million to 358 million years ago. The world looked vastly different then, characterized by two supercontinents, Gondwana and Laurussia, which would eventually combine to form Pangaea.

Part of the Paleozoic Era, the Devonian Period is also called The Age of Fishes, as biodiversity exploded within Earth’s oceans during this time. The ancestors of sharks had their beginning in the Devonian, and a fossilized creature from the Devonian period found in the Canadian Arctic in 2004, called a tiktaalik, is thought to be a “vital link between fish and the first vertebrates to walk on land,” according to National Geographic.

During the Late Devonian period, there was a huge loss of biodiversity that occurred over millions of years. Two extinction pulses, the Kellwasser event and, around 10 million years later, the Hangenberg event, are thought to have finished off the Devonian period for good, leading the planet into the Carboniferous Period.

The Hangenberg Crisis refers to a confluence of events that had a catastrophic effect on the living things of that time. There was a widespread issue with the oceans losing a high percentage of oxygen, called an ocean anoxic event, creating massive dead zones within the seas. There was also a dramatic fall in the sea level around the same time.

According to Tuesday’s paper, recent evidence has suggested that the Hangenberg event at the end of the Devonian was also associated with a depletion of the stratospheric ozone — the layer that filters out dangerous ultraviolet radiation from the Sun.

The new research theorizes that a supernova millions of miles away could have bombarded the planet with ionizing radiation, causing the depletion of the ozone.

A supernova is when a dying star of massive proportions explodes, creating either a neutron star or a black hole in its place, and firing a shock wave of elements, gas and charged particles out into the galaxy.

The researchers believe that if a supernova is responsible, it would have been within around 20 parsecs, or 66 lightyears, of Earth, “somewhat beyond the “kill distance” that would have precipitated a full mass extinction.”

Numerous massive stars capable of producing supernovas live in the Milky Way. A supernova within the distance that researchers have posited would have sent cosmic rays washing over the Earth for around 100,000 years.

“The cosmic ray intensity would be high enough to deplete the ozone layer and induce UV-B damage for thousands of years,” the researchers wrote.

They pointed out that while ozone depletion caused by enhanced convection — one of the other theories surrounding the extinction — is generally geographically limited and episodic, ozone depletion caused by a supernova would be “long lived and global and is therefore much more likely to lead to an extinction event.”

Although ionizing radiation from space is known to be a possible cause of ozone depletion, the research says, this theory has never been applied to this particular mass extinction before.

But is there a way to prove this theory? Researchers say there is, if we inspect the distinct layer of rock in the Earth’s crust that corresponds to the Devonian Period, where fossils and preserved material can allow us to peer into the extinction itself.

If a supernova caused by the core collapse of a massive star was close enough to cause this mass extinction, it would also have peppered supernova “debris” over the Earth as “micron or submicron-sized particles created early after the explosion.”

This would’ve left radioactive isotopes on Earth — distinct versions of chemical elements that are unstable and emit radiation as they decay.

Different radioactive isotopes have different lifespans, meaning “those with lifetimes comparable to the time since the event would provide suitable signatures,” if found within fossils or rock from the Devonian Period.

Researchers speculate that two of the long-lived radioisotopes that could’ve been deposited on Earth — and would be still detectable today — could be samarium-146, and plutonium-244.

The end of the Devonian Period, spurred on by numerous extinction events that severely cut down the level of biodiversity in Earth’s oceans, is still a mystery right now. But if scientists can find these radioisotopes, it may mean that supernovas have played a greater role in our planet’s history and evolution than we ever knew.



Source link

Step forward towards rare earths project north of Alice – Alice Springs News


Arafura Resources says it has reached an agreement with Anmatyerr native title holders for access to its proposed Nolans rare earths mine and processing plant near Aileron, 135 kilometres north of Alice Springs.

 

The agreement paves the way for the Minister for Resources, Paul Kirby, to grant Arafura’s mineral leases, says the company in a media release.

 

IMAGE from Arafura’s website illustrating rare earths use in car engine.

 

The Nolans project will produce Neodymium and Praseodymium (NdPr) “which is in high demand for environmentally friendly, high tech applications such as magnets for electric vehicles, mobile phones, wind turbines and medical equipment,” says Arafura managing director, Gavin Lockyer.

 

“We now have our environmental approvals, this agreement with the site’s native title holders, we have completed our feasibility study and begun awarding key contracts for project management.

 

“Arafura is well-positioned to become a long-term, low-cost, high margin producer of strategic critical minerals needed in a low-carbon, clean-energy world.

 

“The Nolans Project has a likely initial operational life of nearly 40 years and will deliver transformational opportunities for Central Australia, including jobs, economic development and an enhanced logistics capacity in Alice Springs,” Mr Lockyer says.

 

Arafura has a commitment to delivering social as well as economic goals and has worked with the Karen Sheldon Group to prepare an Aboriginal Engagement Strategy for the project.

 

The company is awaiting final advice on its application for Northern Australia Infrastructure Facility funding for key project infrastructure.

 

Subject to raising finance and approval of its mining management plan, Arafura hopes to start work on construction at the site in 2021, says Mr Lockyer.

 

Arafura signed an exploration agreement with the Anmatyerr people in 2005.

 

 

 

Be Sociable, Share!





Source link