Saturday, July 29, 2023

Netflix's 'The Deepest Breath' clip makes for a deeply uncomfortable watch

A world record freedive attempt.
The description of freediving – an extreme sport that involves diving underwater while holding your breath – is already scary enough, but the video above will have you holding your own breath in subconscious solidarity.
Taken from Laura McGann's Netflix documentary The Deepest Breath, the clip shows Alessia Zecchini attempting a world record freedive, starting beside a boat on the water's surface and following a thin line down into the increasingly murky depths.
Zecchini makes it down and back to the surface, but watching her journey is uncomfortable to say the least.

Friday, July 28, 2023

Australia (AHS) layer update in the GeoGarage platform

1841 Lizars Map of Australia, New Zealand, and Melanesia

Advanced ROV vision systems are the future of subsea operations

The Voyis Discovery Vision System inspects a large underwater structure.

From Offshore by Chris Gilson and Patricia Sestari, Voyis Imaging

New technology employs edge computing to capture high-quality stills images in tandem with low-latency video

Subsea inspection operations are an intricate task that have historically required specialized knowledge and complex technology.
ROVs are a critical tool for underwater exploration, inspection and maintenance, but their effectiveness is driven by the quality of their vision systems.
Current ROV cameras prioritize vehicle piloting and situational awareness, which are the most immediate needs of the operators.
However, when both piloting and inspection confidence can be significantly enhanced with 3D information, the industry should seek to adopt new approaches.

Voyis is excited to announce the launch of the new Discovery Vision System, to address the trade-off that is currently made between Piloting Cameras and 3D Inspection Cameras for subsea operations.
Voyis, a company specializing in underwater optical imaging and 3D modeling, has advanced ROV vision systems with new computer vision technology.
The goal was to create a vision platform that could capture both low-latency enhanced video for piloting while simultaneously capturing high-quality stills images for real-time 3D modeling.
The company sought a solution that could generate incredible 3D reconstructions in real time without specialized technicians or expensive third-party processing.

By leveraging edge computing, Voyis' Discovery Vision System streams both crisp 4K piloting video and 3D point cloud data for complete situational awareness, addressing the compromise between piloting cameras and inspection cameras.
Piloting cameras prioritize low-latency video, at the expense of the image data required for 3D modeling.
Conversely, inspection cameras prioritize image data at the expense of piloting effectiveness, limited by their higher latency and a smaller field of view.

The software interface shows 3D model and stills images captured by Voyis Discovery Vision System in real time.

This 3D model was generated by Voyis Discovery Stereo.
Case study

Voyis Discovery and Discovery Stereo have been integrated into the VideoRay Defender ROV.
The Discovery’s capabilities were evaluated on a trial project where an uncharted flooded quarry was explored for the first time during the Canadian winter.
A VideoRay Defender ROV was outfitted with the vision system and deployed through a hole cut in the ice.
The 4K video stream enabled effective piloting to identify a target, while the instantaneous 3D point cloud data was leveraged to evaluate data quality, coverage and to maintain a consistent target range using the added depth perception.
A complete 3D reconstruction was quickly generated using a selected segment of the dataset, attaining a comprehensive set of qualitative and quantitative visual data on the subsea asset—crisp video, high-resolution stills images and an accurate 3D model.
This delivered a complete understanding of the structure and an assessment of its condition.

The system was easily integrated using the vehicle’s existing power and ethernet infrastructure, rapidly deploying this new capability on the small platform.
The Nova Mini lights provided high-intensity, uniform lighting that drastically improved the quality and clarity of the images compared to the standard piloting camera.
In a single day, the Voyis team was able to effectively integrate and operationalize the Discovery in a new environment to acquire an accurate 3D reconstruction of a subsea asset.

The success of the Discovery Vision System highlights its potential to revolutionize subsea inspections and ROV operations, a capability available for small platforms using the compact 300-m Discovery Camera and on large work class ROVs with the 4,000-m Discovery Stereo.
By employing edge computing to capture high-quality stills images in tandem with low-latency video, it achieves a vision system without comprise.
It is now possible for every subsea vehicle to see the depths like the surface is seen.

Links :

Thursday, July 27, 2023

Lost at sea: remembering Thomas Tangvald

From PBO by Kathy Catton

Cruising pioneer Peter Tangvald’s son, Thomas, disappeared after sailing from South America in 2014.

Thomas Thor Tangvald was born at sea on his father’s boat, L’Artemis de Pytheas.
It was 1976, by which time Thomas’s father Peter Tangvald was already a seasoned, competent sailor, having completed a five-year round-the-world voyage on an earlier boat, Dorothea, a 32ft cutter, with no motor, electricity or transmitter.

For Thomas, his life on the ocean, and less so on land, was a dichotomy of restrictions and freedoms.
Sometimes gruelling, sometimes exhilarating and often brutal.
By the age of 15, Thomas had witnessed the deaths of his mother, his stepmother and his father and half-sister.

My path collided with Thomas’s when we arrived at Leeds University in September 1994.
Both aged 18, we seemingly had much in common.
We had a love of languages, a love of sailing, and we both had the desire to find freedom.
But that was where the similarities ended.

Harrowing loss

Thomas Tangvald with his father, Peter, and his half-sister, Carmen.
Credit: Olav Hasselknippe

When Thomas first told me about the shipwreck that killed his father and half-sister on the coast of Bonaire, in the Dutch West Indies, he seemed very casual about it.

It was early in our relationship, and I couldn’t understand how he could recount something so heart-breaking in such a straightforward manner; he almost appeared hardened to the trauma.

But he was not without vulnerability.
As he wrote in the epilogue of his father’s posthumous autobiography, At Any Cost:

“… Then I saw the broad white line, the boiling foam of relentless, charging waves crashing onto the shore.
In seconds L’Artemis was on it, the bow plunging down and the stern rising with such violence as to knock all the wind out of the main.
‘Non! Non!’ I screamed as if it was going to make any difference…”

Thomas described to me how he rushed to grab his surfboard as L’Artemis de Pytheas’s bow slammed into the coral rock.
In complete darkness (there was no moon that night), Thomas struggled to untie the knot securing his surfboard.
Then he jumped into the water to paddle to his father’s boat but realised he might get crushed by it, so he waited several hours for the sun to rise before perilously making his way ashore.

Little did he know at the time that he’d lost his father and half-sister to those wild waters.

Within weeks of this disaster he found himself in the mountainous country of Andorra with his new guardians, Edward and Clare Allcard.

Further education

Thomas’s dream, according to Clare, was to be a yacht rigger.
Realising he was capable of much more with his genius-level intellect, Clare piqued his interest in going to university to study mathematics and fluid dynamics.

She gave him a copy of Stephen Hawking’s book A Brief History of Time and Robert Kanigel’s The Man Who Knew Infinity, a biography on Indian mathematician Srinivasa Ramanujan.
He read them in a day and asked Clare, “What do you have to do to go to university?”

The path was set for our encounter.

When I first met Thomas at Leeds University’s Boddington Hall, one of the first things that struck me was his open smile and massive hair! His accent, his unusual outlook on life, and even the way he walked intrigued me.
It was so smooth, graceful and secure, no doubt the result of a life born and lived at sea.

We hit it off right away and spent hours in his room listening to music and talking about our futures.
He was a purist: a fit, healthy vegan.
He had a commanding presence and a fascination with details.
He saw both the beauty and the pain in nature.
He was completely absorbed in whatever made him feel good, both physically and emotionally.

Thomas was unconstrained by the modern trappings of life; he lacked the ‘socialisation’ filters that inhibited me and would happily climb the walls or roam campus on 2m stilts or engage in more illicit activities, unconcerned about the opinions of others.

“He was like a proper ingénue,” says his good friend, Dan Barton.
“An amazing intellect with no formal schooling, a child of nature, deposited in modern society.”

Thomas Tangvald
Afloat again

In his final year of his studies at Leeds he bought Melody in the River Blackwater on the north side of the Thames estuary.

Melody was a 22ft traditional Itchen Ferry cutter, built with oak frames, teak hull planking and a pine deck.
She carried a modern Bermudan mainsail and was ballasted with lead – half of it fixed in her keel, the rest loose in her bilge.

Thomas wrote to me of his journey sailing Melody north up the east coast to the Humber River and then up the Ouse and the Aire, as close as he could get to Leeds:

“Going from Harwich to Southwold the wind got lighter and lighter until I was becalmed.
My battery ran out… [and hence no navigation lights] and there was a tremendous amount of shipping… I was getting quite worried that the tide would sweep me onto some shoals, but I just managed to avoid them.”

Thomas would happily embark on voyages such as this with very rudimentary tools and systems.
He would rely on gut instincts and natural skill.

Sailing with no more than a small tracing from another yachtsman’s map, he found himself travelling from Southwold for the Humber, sat mid-shipping channel with the tide against him unable to manoeuvre or signal his presence.

Unfortunately he hadn’t marked a weir blocking the way, so he had to go all the way back down the Aire onto the Ouse again, up to Selby, where I met him for an afternoon before lectures began again.
I was amazed to see how well resourced he was, albeit without a proper map or functioning compass.

Although Melody was scruffy, there were plenty of smaller tools, and stationery stored on the boat, as I remember.
And he was very much at ease on board.

He later wrote: “I don’t think I’ve ever felt as alive as when I was sailing,” and, “It made me realise just how … little freedom most people have.
Most humans live hardly at all – they might as well be dead for all the shields they have put in between themselves and L I F E.”

Haunting mystery

But behind his smiles and delights at being on board again, to me, he still had tears behind his eyes.
A thinly veiled façade couldn’t always hide his hurt and suffering.

But his sailing life continued.
After completing his studies, he sailed single-handed across the Atlantic to the Spanish Virgin Islands and other islands in the Caribbean.

At the age of 27, he met his wife, Christina, and over the space of six years, they had two boys.
In March 2014, aged 37, Thomas set sail alone in an ill-equipped and vulnerable boat, Oasis, from the coast of French Guiana, bound for the Brazilian island of Fernando do Noronha.

Sadly, he was never seen again.

The full and complex story of this remarkable and vulnerable man is now told by marine journalist Charles J Doane, in his book The Boy Who Fell to Shore: The Extraordinary Life and Mysterious Disappearance of Thomas Thor Tangvald.

Although it’s a haunting and harrowing story, it’s a riveting account of a terrifying and tragic life.

Author Charles, with whom I corresponded about the book as he was writing it, writes beautifully in a non-judgemental, compassionate manner.

Links :

Wednesday, July 26, 2023

The seaweed blob is heading to a beach near you

Photo : Olivier Morin / Getty Images

From Wired by Chris Baraniuk

The 5,000-mile-wide Great Atlantic sargassum belt has started to shrink.
But it's very difficult to know where its decomposing remains will wash up.

EVERY DAY, CHRISTINE Jimenez-Mariani flips open her laptop and starts sorting through the latest pictures of rotting piles of seaweed that have landed in her inbox.
The dozens of images she receives each day generally come from people visiting beaches around the Gulf of Mexico—in areas like Florida, Belize, and Brazil.

“They trust in me,” says the French retiree, who lives in Cancún, Mexico.
She spends roughly 10 hours a day sorting through photos and videos that show piles of the frilly, yellow-brown seaweed, called sargassum.
“It’s totally voluntary, I am working for nobody,” she says.

Five years ago, Jimenez-Mariani realized that people wanted to find out whether their vacation destination had been hit by a spate of sargassum—at its worst, the stuff can wash up and completely cover the shoreline.
But it was hard to get that information.
So she set up Sargassum Monitoring, a website with a live map of reported seaweed inundations on beaches.
The site gets 1 million views every month, she says, and she also shares pictures on Twitter, Facebook, TikTok, and other social media sites.

Scientists have also been tracking sargassum in great detail.
Monthly bulletins from the University of South Florida suggest there’s a significant amount of the seaweed around beaches this year, compared to most previous years, although the volume out at sea has been decreasing lately, dropping 15 percent between April and May.
Further decreases in July and August are expected, but researchers say it’s hard to know exactly how much will end up on land.
Florida, bracing for huge amounts to make landfall, has largely been spared the extreme amounts that washed up last year.
Elsewhere, such as in Cancún, beachgoers haven’t been so lucky.

The amount of sargassum blooming in the Atlantic rocketed in 2011, and since then, sprawling drifts of the algae have been cluttering beaches to a much greater extent than anyone can remember.
The problem also affects coastlines in Africa.
No one is quite sure why sargassum boomed 12 years ago, but a shift in wind patterns is one possibility.
The seaweed grows in the Sargasso Sea, from which it takes its name, and then floats in a long belt that sometimes stretches for thousands of miles.
When it washes ashore, the algae piles up and, within a few days, begins to decompose.

“The odor is very, very bad,” says Jimenez-Mariani, who has encountered the phenomenon herself on the beaches of Puerto Morelos in Mexico.
“It’s like rotten eggs.” That particular smell is thanks to the hydrogen sulfide, a toxic gas spewed out by the deteriorating algae.

Besides Sargassum Monitoring’s output, there are various other ways to find out where sargassum is showing up—from Facebook groups to reports published by scientific institutions.
And yet it remains difficult to predict how bad the decomposing sargassum will be in any given year.
In March, CNN published a story headlined “A 5,000-mile-wide blob of seaweed is headed for Florida,” but scientists using satellite data have since observed a decrease in the total abundance of sargassum.

Some reports have also sparked fears of “flesh-eating bacteria” among the algae, but there is no evidence for this.
When people come into close contact with rotting sargassum, they can experience health problems, including diarrhea, vomiting, and eye irritation, so it is sometimes more than just an inconvenience.
Plus, while local authorities have spent millions removing sargassum from beaches, they have invariably extracted large volumes of sand in the process, accelerating coastal erosion.

Given the issues caused by the seaweed, researchers are looking for better ways to monitor its movements so they can understand what factors influence the extent—and trajectory—of sargassum blooms.
“This year was very curious,” says Gustavo Goni, of the National Oceanic and Atmospheric Administration’s (NOAA) Atlantic Oceanographic & Meteorological Lab, recalling the record volumes of sargassum that scientists detected floating at sea in the first few months of 2023.
They reached a peak around March, after which, in a highly unusual turn, the sargassum glut began to shrink.

NOAA publishes a regularly updated sargassum report online that estimates the risk of beach inundations around the Gulf of Mexico.
The administration works with the University of South Florida to produce this information, and the university also puts out separate data gleaned from satellite monitoring.
This reveals that the sargassum belt was particularly extensive during May in 2018, 2021, and 2022, while in May 2023 it was less so, though not by much.
“This year is still a major sargassum year,” says Chuanmin Hu at the University of South Florida.

Satellite-derived snapshots of the seaweed’s spread are crucial, but they don’t reveal exactly what inundations are like on the ground.
Hu and his colleagues collect data from the field, but members of the public also play a role.
“We very much need citizen science,” says Goni, noting that people can send pictures and videos of the seaweed to NOAA via the sargassum report web page.
Jimenez-Mariani adds that she frequently shares reports of sightings with scientists.

Hu says that many factors might influence the growth and flow of sargassum, as well as whether it actually ends up on a beach—from light levels to ocean currents, winds, temperature, and tides.

To better track the movement of the algae out at sea—before it causes issues on land—Linda Amaral-Zettler at the Royal Netherlands Institute for Sea Research and colleagues are working on ways of tagging the sargassum, or planting drifters in the middle of large floating clumps of it.
“The idea is to get one stuck in a patch and have it move with a patch,” she says of the drifter devices they are developing.

The tricky part is that floating sargassum often sinks after a little while.
“The probability of a tag being lost is relatively high,” says Amaral-Zettler.
She says there are more than 350 species of sargassum, but most don’t float on the sea surface at all—only a few species are responsible for the large drifts that have been causing problems for tourists and locals in beach towns in recent years.
Away from beaches, sargassum provides an important habitat for turtles and some fish.

Amaral-Zettler’s research has also delved into the complex microbiome associated with the seaweed.
In two papers published earlier this year, in February and May, she and colleagues described various kinds of bacteria that they found on samples of the algae, including species from the genus Vibrio, which could possibly be pathogenic to humans.
“The prevalence of Vibrio was a bit eye-opening—that was not anticipated, necessarily,” she says.

Some media outlets referring to the May study claimed that scientists were concerned about flesh-eating microbes.
Amaral-Zettler says this was a misinterpretation.
Lead author Tracy Mincer at Florida Atlantic University told local media: “That’s not what we were saying at all.
It just became this clickbait, and everybody started trying to hype it up.”

According to Alfred Lea at the University of Texas Medical Branch, the rotting sargassum found on beaches can emit both ammonia and hydrogen sulfide gasses, which can irritate your nose and throat, or cause breathing difficulties if you have asthma or other sensitivities.
But the breezes at most beaches will naturally dilute these gasses, he says, greatly reducing the risk.

A 2021 paper reporting health problems experienced by 154 patients in the Caribbean in 2018 described a range of symptoms caused by exposure to rotting sargassum, including headaches, conjunctivitis, skin irritation, and vomiting—though participants’ mean exposure time to the putrefying seaweed was significant: three months.

While sargassum inundations can present a health risk, it is clearly localized and easily managed as long as you can steer clear.
The bigger questions—what influences sargassum blooms and why more of it washes ashore one year versus the next—remain key areas of scientific inquiry, and there are no clear answers yet.

As we wait for those, Jimenez-Mariani says she will continue to flag sargassum flare-ups based on the photos and videos sent her way, in an effort to inform tourists and residents of coastal towns affected by the algae.
“I try to do my best to help these people,” she says.
“This is very, very important to me.”

Links :

Tuesday, July 25, 2023

Scientists discover ancient, underwater volcano is still active — and covered in up to a million giant eggs

The 2023 Northeast Pacific Deep-sea Expedition team has returned after two weeks at sea on what has been described as an unprecedented expedition.
For the first time, a science expedition has explored life at all three of BC’s deep-sea biodiversity hotspots—seamounts, vents, and seeps—discovering and documenting vibrant communities, unique phenomena, and captivating never-before-seen behaviours.
It is globally rare for these ecosystems to occur together, in such extremely high densities, and in domestic waters, but BC’s deep sea boasts an incredible concentration of seamounts, hydrothermal vents, and cold seeps owing to the region’s uniquely small, active, and nearshore tectonic plates.
The expedition’s objective focused on science that will contribute to a better understanding of these remarkable and fragile ecosystems and inform marine conservation planning.
However, the unexpected discoveries and personal encounters with deep-sea animals have left scientists and the global public speechless.

From LiveSciences by Sascha Pare
Researchers discovered that an underwater volcano nearly a mile beneath the surface off the Pacific coast of Canada is spouting hot fluid, providing a little-known species of skate with an ideal nursery.

The summit of the seamount was covered in thousands of giant, ravioli-shaped eggs.
(Image credit: NEPDEP 2023)

Researchers exploring an ancient, underwater volcano off the Pacific coast of Canada have discovered it is still active — and "covered" in thousands of giant eggs.
STRM bathymetry in the GeoGarage platform
Before the expedition, the team thought the volcano was extinct and the waters around it frigid.
However, they found the underwater mountain — which towers 3,600 feet (1,100 meters) above the seafloor — spouting warm water and encrusted with deep-sea corals.
The hot, mineral-rich fluid keeps the surrounding waters toasty, providing ideal conditions for some marine creatures to survive in the deep sea.
The researchers were even more surprised to see a Pacific white skate (Bathyraja spinosissima) weaving in and out of the fronds and laying eggs on the summit, nearly a mile (1.5 kilometers) beneath the surface.

"It's a really special place on top of a really special place," Cherisse Du Preez, a deep-sea marine biologist with Fisheries and Oceans Canada and principal investigator on the expedition, told Live Science in an email.
"The only previous finding of a Pacific white skate nursery was in the Galapágos and I think was on the order of a dozen or two eggs."

Researchers recorded the first ever footage of a female Pacific white skate (Bathyraja spinosissima) laying eggs. 
 Image credit: NEPDEP 2023 (Screenshot from YouTube)

Du Preez said the recently found skate nursery is many times the size of that.
"I'd estimate the summit of the seamount, which was covered in eggs, had — I don’t know — 100,000? A million?"
These eggs were large, Du Preez added, measuring about 1.5 feet (0.5 m) across.

The researchers were also the first ever to record footage of a Pacific white skate laying eggs, they said in a video of the expedition (see above)

Pacific white skates are little-known sea creatures related to sharks and rays.
They are among the deepest-dwelling species of skate, inhabiting depths between 2,600 and 9,500 feet (800 to 2,900 m) off the west coast of North and Central America, according to the IUCN Red List.
Adult females, which can grow up to 6.5 feet (2 m) long, lay rectangular eggs, which are known as "mermaid purses" because they look like little bags, Du Preez said.

Pacific white skates (Bathyraja spinosissima) are little-known marine creatures related to sharks and rays.
(Image credit: NEPDEP 2023 (Screenshot from YouTube))

In 2018, researchers discovered several of these ravioli-shaped eggs close to hydrothermal vents near the Galapágos Islands, suggesting skate moms harnessed the volcanic warmth to incubate their eggs.
The new observations point to the same conclusion, Du Preez said.
"It takes four years for the young to develop," she explained.
"The warm water likely speeds up the gestation period of the eggs, resulting in more successful juveniles.
The shallow summit of the seamount is almost a coral garden and a safe nursery for juveniles to grow before they descend to the deep — it's a win-win."

The researchers will continue to monitor the egg-covered seamount, which is not currently protected and may be threatened by fishing activities.
The discovery shows just how important vent habitats are as nurseries and to the overall health of the ocean, Du Preez said.

Links :

Monday, July 24, 2023

Fukushima’s radioactive water is going to be pumped into the ocean—and that’s fine

Photograph: Philip Fong /Getty Images

From Wired by Chris Baraniuk

Fukushima’s Radioactive Water Is Going to Be Pumped Into the Ocean—and That’s Fine
Japan’s plan to treat, dilute, and discharge the irradiated water used to cool Fukushima’s nuclear reactors is unpopular, but experts say it’s safe.

In satellite pictures, they look like the pale blue and gray eggs of a giant butterfly, laid in tight patterns on some dismal leaf.
The eggs, made of steel, are tanks brimming with radioactive fluid—contaminated water from Japan’s Fukushima nuclear plant.
The water will soon be diluted and pumped into the sea.
Núria Casacuberta Arola, of ETH Zürich, is among those who will be watching.

“We have access to a ship that goes to the coast of Fukushima every year, sometimes once, sometimes twice,” she says.
Casacuberta Arola and her colleagues regularly drop an assembly of jars into waters near the incapacitated power plant to collect samples at different depths.
The lids of the jars close automatically, one by one, as the device is slowly pulled back up to the surface.

By doing this, and also taking sediment samples from the seabed, they hope to be able to tell in the coming months and years whether the disposal of water from Fukushima is causing a noticeable rise in radiation in this corner of the Pacific Ocean.
The water release could start as early as next month.
If there is a significant bump in radiation levels in the surrounding waters, it will mean things have gone very wrong.

In 2011, a massive tsunami struck Fukushima Daiichi Nuclear Power Station.
The defensive sea wall intended to protect the plant from such an onslaught was many meters too low to stop the monster wave.
Seawater flooded the facility, ultimately leading to partial meltdowns and huge explosions at some of the reactors.
It is considered one of the worst nuclear accidents in history.

In the years since, workers have had to constantly pump water into Fukushima’s stricken reactors, which still contain hot nuclear fuel.
This water has, thankfully, done its job of keeping the reactors cool, but it has become irradiated in the process, meaning it can’t just be flushed away.
Workers have kept the used cooling water on-site, building tank after tank in which to store it.
All the while, they have known that they will eventually have to dispose of it.
Today, there are 1.3 million metric tons of contaminated water on-site.
And no space for any more tanks.
The time to do something about it is here.

It has taken years of research, modeling, and sampling, but earlier this month the International Atomic Energy Agency gave its approval for a discharge plan.
Japan’s Nuclear Regulation Authority signed off on the proposals at the same time, meaning that the Tokyo Electric Power Co (Tepco), which is in charge of the plant and its cleanup, has full authority to begin slowly releasing the water into the ocean via a 1-km-long underwater pipe.

Some aren’t happy.
Local fishers are strongly opposed to the plan, and there have been street protests in South Korea.
Yet many scientists are highly confident that the discharge will be perfectly safe.

Since the 2011 Fukushima nuclear disaster, more than 1m tonnes of radioactive water has been building up at the power plant in central Japan.
Soon the plant will run out of space to store the water, which is a big problem.
The plan at the moment is to dump it all in the sea.
So how do you go about making 1m tonnes of radioactive water, safe to drink?
The contaminated water, enough to fill more than 30,000 fuel-truck semi-trailers, contains a mix of unstable chemical elements, known as radionuclides, that emit radiation.
To keep these radioactive components to a minimum, Tepco has installed special water purification technology that treats the water before storage.
In essence, it involves passing the contaminated water through a series of chambers containing materials that can adsorb radionuclides.
The isotopes stick to those materials and the water flows on, a little cleaner than before.

However, it is not 100 percent effective, and many of the radionuclides it’s designed to extract, such as the isotopes caesium-137 and strontium-90, for example, can still be found in the stored water.
There are also some isotopes the system can’t remove at all, such as carbon-14 and tritium, a form of hydrogen with two neutrons and one proton in its nucleus (hydrogen usually contains just one proton).

Despite this, the water is extremely safe because the concentrations of radionuclides are so low, explains Jim Smith, a professor of environmental science at the University of Portsmouth.
“I’m not concerned,” he says of the plan to discharge the water.

Many of the above radioactive isotopes were released into the ocean at the time of the disaster in 2011—and some traveled.
One study found them floating around 3,000 km away in the Arctic Ocean six years after the accident.
Once the discharge begins, radionuclides will undoubtedly spread out into the Pacific, but this is very unlikely to have a noticeable effect on the environment, Smith says.

For context, he points out that he has many years of experience studying the effects of radiation on living things near the destroyed nuclear power plant in Chernobyl.
Even there, where exposure to radiation is much greater, the impact appears to be tiny.
“We know radiation damages DNA, probably there are subtle effects of radiation at these levels, but we don’t generally see a significant effect on the ecosystem,” he says, referring to that work.

Plus, tritium—one of the isotopes that can’t be removed from the stored water—is already present all around us at low concentrations, though higher levels are associated with nuclear-related activities.
The authors of one 2018 study speculated that unusually high levels of tritium in the Rhône river delta in France were down to historical pollution from the watchmaking industry—tritium has been used to make glow-in-the-dark paint for watch dials.

What many people don’t realize is that water containing tritium is actually routinely released into the sea—sometimes in vastly greater quantities than are to be discharged from Fukushima—by nuclear facilities all around the world, including in the US, Europe, and East Asia.
The Cap de la Hague nuclear processing site in France releases 11,400 terabecquerels (Tbq) of tritium every year, which is more than 13 times the total radioactivity of the tritium across every storage tank at Fukushima.

Tepco is regularly testing the stored water ahead of the release, the company says.
The water will be re-treated, multiple times if necessary, and diluted more than 100 times to bring its tritium radioactivity concentration down to no more than 0.0000000015 TBq per liter, a level equivalent to a 1/40 of Japan’s national safety standards.
Roughly 70 percent of the stored water also contains radionuclides other than tritium that are at concentrations exceeding regulatory limits, says the Japanese government—levels of these will also be brought down to below Japan’s regulatory standards. The water will then be tested again before being discharged.

For a final point of comparison, Smith calculates that cosmic rays interacting with the Earth’s atmosphere over the Pacific Ocean annually cause the natural deposition of 2,000 times more tritium than will be introduced by the gradual Fukushima release.

Tatsujiro Suzuki at Nagasaki University remembers watching in horror as the disaster unfolded back in 2011.
“We all thought that this kind of thing would never happen in Japan,” he says.
At the time, he was working for the government.
He recalls the confusion over what was happening to the reactors in the days following the tsunami.
Everyone was gripped by fear.

“Once you experience that kind of accident, you don’t want to see another one,” he says.
The long shadow cast by the disaster means that, for the water release plan, the stakes—at least in terms of public trust—could not be higher.

Suzuki argues that it’s not quite fair to compare the Fukushima water to fluids discharged from other nuclear facilities elsewhere in the world because of the challenge of cleaning up the many different radionuclides here.
“This is an unprecedented event, we have not done this before,” he says, adding that he thinks the procedure is “probably safe” but that there is still room for human error or an accident, such as another tsunami, that could cause an uncontrolled release of the water into the sea.

Tepco and the International Atomic Energy Agency have considered such possibilities and still judge the risk to human and marine life to be extremely low.
Sameh Melhem, now at the World Nuclear Association, formerly worked for the Atomic Energy Agency and was involved in some of the research to evaluate the discharge plan.
“I think it’s very safe for the operators themselves and also for the public,” he says, adding: “The radionuclide concentrations coming from this release, it’s negligible.”

Last November, Casacuberta Arola and her colleagues collected samples of seawater off the coast of Fukushima, and they have recently begun to analyze them.
The scientists measure the levels of various radionuclides that might be present.
For tritium, that means removing all helium from the sample and waiting to see how much new helium emerges from the water as a product of radioactivity.
This makes it possible to extrapolate the amount of tritium that must be present, explains Casacuberta Arola.
She and her team have records of radionuclide measurements like this from the sea off Fukushima going back years.

“We already know that the values that we see now close to Fukushima are close to the background values,” she says.
If that changes, they should find out fairly quickly.
As will the International Atomic Energy Agency and other observers, who, separately, intend to sample water and wildlife in the area in the coming years to keep an eye on things.

Smith says that despite overwhelming evidence that the water release will be entirely safe and heavily scrutinized at every turn, it is not surprising that some people are skeptical of the plan.
They have a right to be, he adds, given the troubled history of the plant.

At the same time, the threat posed by the release—even in a worst-case scenario where everything goes wrong—is miniscule compared to some of the other environmental risks in the region, such as the effects of the climate crisis on the Pacific Ocean, Smith says.

Casacuberta Arola agrees.
Negative coverage of the discharge plan has been used to “brainwash” people, she argues, and to instill fear against the nuclear energy industry.
“To me,” she adds, “it’s been very much exaggerated.”

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Sunday, July 23, 2023

Charley Morgan 1970 America's Cup clips. Heritage

Miss this type of America's Cup.
Heritage was competing to defend, the cup. Charley was awesome.