Saturday, July 8, 2023

At this exact time every year more than 90% of the world’s population are in sunlight

Map source:
From AustralianGeographic by Dr Karl Kruszelnicki

On Reddit, I came across the following statement: 
“Every year on 8 July at about 11.15 Coordinated Universal Time (UTC), approximately 99.164 per cent of the world’s population is between dawn and dusk.”
Amazingly, it turns out to be only 6 per cent wrong!

How come? First, about 90 per cent of all humans live in the Northern Hemisphere.
Second, Earth is tilted from the vertical by about 23.5 degrees.
During the June solstice (21–22 June), the North Pole is in continuous 24-hour sunlight.

The map provided shows where sunlight falls on the planet at 11.15 UTC on 8 July (a few weeks after the June solstice).
Both Australia and New Zealand are in darkness but carry less than 1 per cent of humanity.
Nightfall just misses the Americas, Asia, Japan and Taiwan.
So 83 per cent of humanity were between dawn and dusk.

The fuzzy boundary on the map is the three twilights.
Civil twilight runs from when the Sun drops below the horizon until the centre of the Sun is 6 degrees below the horizon.
There is still enough light to see – another 7 per cent of humanity, bringing us to 90 per cent.

Nautical twilight runs from when the centre of the Sun drops to 12 degrees below the horizon.
There’s enough light to walk around safely early in nautical twilight, but not in late nautical twilight.
About 6 per cent of humanity is in nautical twilight at 11.15 UTC on 8 July, so let’s add another 3 per cent (half of 6 per cent) to our total.
Now we have 93 per cent of humanity between dawn and dusk, and 3 per cent in darkness.

During astronomical twilight, the centre of the Sun drops to 18 degrees below the horizon.
This is effectively night-time, so that’s another 3 per cent in darkness.
Astronomers recognise three stages of twilight – civil, nautical and astronomical.

Australia, New Zealand and New Guinea are also in full darkness – another 1 per cent (total of 7 per cent).

But why pick a day a few weeks after the June solstice?
Indonesia and the Philippines, near the Equator, are highly populated.
They are partly in the dark on the actual June solstice.
But if you give just a few more weeks for the Sun to move further south, light falls on an extra 10 million people.

On 8 July, at 8.15pm Australian Eastern Standard Time, about 93 per cent of the world’s population had enough light to see what they were doing (and 7 per cent did not).
That’s not 99.164 per cent, but it’s still a surprisingly large percentage of the population.

Friday, July 7, 2023

New volcano, old caldera

Scientists are puzzled about the origin and seismicity of a submarine volcano in the Indian Ocean near the island of Mayotte, Comoros.
From EOS by Alka Tripathy-Lang 

Researchers suggest a magma chamber sits within an old submarine caldera structure that extends into the mantle.

In May of 2018, a barrage of earthquakes struck Mayotte, the seismically quiet easternmost island of the Comoros archipelago, which stretches between Africa and Madagascar.
After months of investigating the unexpected, intense seismic activity, French scientists discovered a new submarine volcano in the Indian Ocean approximately 50 kilometers east of the island.
This new seafloor feature is, by volume, the largest documented underwater volcanic eruption in history, and both volcanic and seismic activities continue today.

In the years since the initial quakes, teams of scientists have refined the picture of the structures below the seafloor.
Building on this foundation, marine geologist Nathalie Feuillet and seismo-tectonicist Eric Jacques, both at the Institut de Physique du Globe de Paris, and their colleagues proposed the presence of a large underwater caldera—a volcanic depression formed when a magma chamber drains and collapses—located between Mayotte and the new volcano.
A ring of earthquakes in the mantle lithosphere delineates this curious structure at depths where neither earthquakes nor calderas typically occur.

Feuillet, Jacques, and other researchers will present their findings at AGU’s virtual Fall Meeting 2020.
Mayotte island with the GeoGarage platform (SHOM nautical raster chart)

A Timeline of Peculiar Events

Mayotte formed approximately 11 million years ago and is the oldest in the chain of Comorian volcanic islands, said Feuillet in her prerecorded talk for the AGU event.
The island slumbered until 10 May 2018, and in the first 2 months of the seismic episode, more than 100 events greater than magnitude 4.5, including a magnitude 5.9 event, rocked the island.
Its population, accustomed to stable ground, had only a single seismic station to monitor the sudden crisis.

In November 2018, seismic stations around the world heard a mysterious hum that scientists traced to Mayotte.
This 25-minute-long signal vibrated at low frequencies, hinting that magma movement and volcanic activity were the prime suspects to explain the seismic crisis.
Back at sea level, Feuillet said local fishermen reported “dead fishes” and a “burned tire smell” during this time.

In May 2019, the first of seven marine cruises confirmed that 5 cubic kilometers of lava had piled onto the previously flat seafloor, constructing an 800-meter-tall volcanic edifice, said Feuillet in her talk.
The presence of hydrogen gas in the water column indicated that the nascent volcano was actively erupting into the sea during the scientific cruise.
With each subsequent campaign, scientists discovered fresh lava flows, she said.

From Seafloor to Mantle

East of Mayotte’s shores, Feuillet described “the crown,” a circular structure on the seafloor approximately 10 kilometers in diameter and dotted with many cones.
She and her colleagues interpreted the structure as the outline of an old caldera.
An oceanic ridge stretches eastward, away from the crown, truncated by the fledgling volcano 50 kilometers from Mayotte.
In this map of the topography and bathymetry of Mayotte, the red triangle indicates the new volcanic edifice.
The orange circle indicates the primary donut cluster of earthquakes below the possible caldera structure.
The green ellipse encloses the secondary cluster parallel to the ridge.
The red triangle at the end of the green ellipse denotes the new volcanic edifice.
Credit: Lise Retailleau; bathymetry from GEBCO, SHOM HOMONIM, and REVOSIMA MAYOBS1; topography from IGN
To explore the structures in the lithosphere below the seafloor, Jacques, Feuillet, and their colleagues focused on two distinct clusters of earthquakes.
The eastern cluster, located between the suspected caldera and volcano, concentrates earthquakes deep below the seafloor, parallel to the ridge, said Jacques.
This cluster includes the inaugural earthquakes from May and June 2018, which Feuillet said may indicate that a dike propagated from west to east before the eruption, pushing magma from a deep western reservoir eastward and upward toward the volcano, similar to the model proposed in a paper published earlier this year.

The donut-shaped western cluster began shaking in the summer of 2018.
Earthquakes tell scientists where faults are breaking, so this ringlike cluster implies faults arrayed in a circle mirroring the possible caldera directly above.
At depths of 25 to 55 kilometers, these earthquakes nucleated in the mantle below the local depth of the Mohorovičić discontinuity, said seismologist Wenyuan Fan in an email.
Fan, an assistant professor of geophysics at Scripps Institution of Oceanography, is not affiliated with the new studies.
Earthquakes usually rupture brittle crust, where strain energy can accumulate, he said.
Strain cannot accumulate at typical mantle conditions, so most mantle tends to flow, inhibiting the breaks of earthquakes.Mayotte is not related to subduction, leaving these mantle earthquakes a mystery.“One way to [get mantle earthquakes] would be to bring down cooler materials that can host earthquakes,” Fan said, which happens in subduction zones.
But the Mayotte events are not related to subduction, leaving these mantle earthquakes a mystery.

How the western donut cluster connects to the eastern ridge cluster poses another quandary because they are not linked by earthquakes, said seismologist Lise Retailleau, also of Institut de Physique du Globe de Paris but not part of Feuillet’s and Jacques’s studies.
Whether the lack of seismic connection between the clusters indicates aseismic magma transfer or some deeper connection hidden from scientists, she said, “we don’t really know.”

Also perplexing are observations of the lithosphere between the proposed caldera and the donut cluster.
Retailleau pointed out that the caldera shows no evidence of volcanic activity at the human timescale, even though most of the seismicity recorded since 2018 congregates below it.
Even stranger, the upper crustal lithosphere between the surface and the top of the donut cluster lacks earthquakes that indicate breaking, brittle crust.
Instead, long-period and very long period seismic events associated with this eruption—events that often imply magma movement—occur just above the donut, said Retailleau.
Feuillet said that these events might foreshadow another untapped shallow magma chamber above the brittle rocks defined by the donut cluster.
If this magma chamber is active and continues its upward path, Retailleau said it could affect Mayotte and its population of more than a quarter million people.
“That’s a big question,” she said.
Links :

Thursday, July 6, 2023

Mutiny on the Bounty and the scandalous history of Pitcairn Island

Fletcher Christian and the mutineers set Lieutenant William Bligh 

From History Defined by James R. Coffey

The mutiny of the HMS Bounty on April 28, 1789, is unrivaled in the annals of rebellions in Naval history.

Brought to mainstream awareness, primarily by three highly-successful major motion pictures (in ’35, ’62, and ’84) based on the Charles Nordhoff and James Hall historical novel Mutiny on the Bounty, these films focus primarily on the events that triggered the mutiny and the mutineers’ subsequent efforts to elude punishment.

However, the scandalous history of Pitcairn Island, the mutineers’ unintended final destination, is more fascinating.
The place where the violations they perpetrated at sea pale compared to the scandalous transgressions they’ve since perpetrated on land.

The Ambitious Mission

The HMS Bounty was a three-masted, 91 feet long by 25 feet-wide armed vessel of the “cutter” class and technically a Royal British Navy warship.

Commissioned at the urging of Sir Joseph Banks, president of the Royal Society, the Bounty was charged with collecting and transporting breadfruit plants from the South Pacific island of Tahiti to the British colonies of the West Indies.

Banks championed the view held by many Caribbean plantation owners that breadfruit might flourish in the West Indies and be a cheap food source for the growing slave population.

Command of this ambitious mission was given to Lieutenant William Bligh, with Sailing Master John Fryer, Master’s Mate Christian Fletcher, and several other warrant officers filling the ranks–either hand-picked by Bligh himself or appointed by the Navy Board.

To successfully achieve the grand design of the expedition, the Bounty was refitted to accommodate over 1000 potted breadfruit plants–which meant Bligh and his crew of 46 men (which included two botanists) would be subjected to severe overcrowding for the duration of the voyage, which would ultimately involve circumnavigating the globe.

In December of 1787, the Bounty departed England for Tahiti and arrived ten months later, in October of 1788.
During these 10 months, tensions between Bligh and his crew, who considered him an oppressive and insulting commander, had become intolerable.

The relationship between Bligh and Master’s Mate Christian Fletcher was particularly strained.
During the five months it took to collect, pot, and secure the breadfruit saplings for the return voyage, the crew became so adapted to Tahitian life that many decided to abandon the mission and remain there (Fletcher Christian himself had taken a Tahitian wife).

As the departure date neared, three crew members chose to desert rather than leave the idyllic life they’d come to love.

The Mutiny

On April 4, 1789, the Bounty departed Tahiti for the West Indies, forcing many crewmen to leave the life of peace and tranquility they much preferred over what they faced on the open sea with Bligh.

Within a few days, Bligh’s abuse of the crew again reached intolerable levels, accusing some of them of stealing coconuts from the ship’s store and threatening severe punishment.

While there is no documented accounting of the coconuts on the Bounty, it is known that they were commonly kept on board for long sea voyages as a source of potable water, high-calorie food, fiber that can be fashioned into rope, and shells that can be turned into charcoal.
Additionally, coconuts can be used to construct a flotation device in an emergency.

Fletcher Christian, growing increasingly unnerved by the abusive treatment he and the crew were receiving, reached the point where he could not seize control of the ship.

On April 28, Christian and several members of the disgruntled crew relieved Bligh of command and then forced him and eighteen men loyal to him into a 23-foot boat built to accommodate 12, setting them adrift on the open sea.

Christian immediately altered course in search of an uninhabited island where he and his fellow mutineers could take refuge.
Finding none, he returned to Tahiti, where he dropped off those who wished to remain on the island, then recruited twelve female and six male islanders (and reportedly one child) to man the Bounty.

Loading whatever provisions were available, he then resumed his search for an island where he and his crew could hide from the authorities he knew would invariably pursue.

In January of 1790, the Bounty settled on Pitcairn Island, an isolated, uninhabited volcanic rock a little more than 1000 miles east of Tahiti.

Meanwhile, the mutineers he delivered to Tahiti were captured and taken back to England, where three were hanged for mutiny.
The British ship searched for Christian, and the others never found them.

Pitcairn Island: Desperate Times, Desperate Measure

Despite the crew’s best efforts to ensure their survival, the Bounty mutineers and their Tahitian collaborators were never far from oblivion.

While initially, each mutineer had a wife (three women were shared by the six Tahitian men, apparently within their custom), equanimity on the island was destroyed when one mutineer’s wife died, prompting him to poach the wife of two Tahitian men.

This unforgivable betrayal set off a wave of widespread upheaval that continued for more than ten years and left only three men alive, Fletcher Christian among those murdered.

By the time an American whaling ship happened by this outlying island in 1808, only one man, John Adams, remained alive (along with an unknown number of women and children), and the unconventional mating habits the Bounty men had instituted to perpetuate survival were already in full swing.

Habits proved relatively successful for over two centuries.
But then the present collided with their past in a most unforeseeable way.

Public Scandal and Long Arm of the Law

In 1999 a female island resident mentioned in passing Pitcairn’s long-standing mating practices to a visiting British policewoman.

This ignited an in-depth international inquiry seeking to depose every living Pitcairn female residing on and off the island (per British law).
This investigation led to many years of accusations, revelations, issues of legal jurisdiction—and, of course, an eye-opening education in Pitcairn Island history.

During the preliminary inquiry, it was discovered that Pitcairn Island’s population peaked in 1937 when it approached 250.
But since that time, even with what the public viewed as “scandalous” mating habits, the relatively-isolated occupants of the island had struggled to maintain a sustainable population. 

Pitcairn Islander, 1916

In September of 2004, a panel of 20 judges, lawyers, and full court staff effectively invaded Pitcairn Island, intent on bringing the accused to justice.
It should be noted that while several of the women said they would like the mating practices to stop, none filed formal charges nor demanded it.

Seven Pitcairn men (about half the male population) were formally changed with fifty-five counts of rape, indecent assault, and sexual abuse of girls as young as five years of age, stemming from changes dating back to 1964.
Several women were also investigated as accomplices or facilitators but never charged.

Eight accusers, whose testimonies were transmitted via video conference to the makeshift courtroom from New Zealand, where most of them then resided, described Pitcairn as a society where men do pretty much whatever they want, with abuse and rape as the normal way of life.

But while several Pitcairn women confirmed girls’ initiation into sexual relationships by age 12, a number of them said these relationships are purely consensual—not forced–and are considered normal on Pitcairn.

Most acknowledged that without their unusual mating habits, Pitcairn would have ceased to exist long ago.

Defense for the Pitcairn accused argued that British authority does not apply to the descendants of the Bounty mutineers because they de facto renounced British citizenship when they staged the mutiny and then founded the colony.

And beyond the moral and legal implications these proceedings entail, most families have a defendant, an accuser, or both involved–making objectivity impossible.

During the trial, it was pointed out that Pitcairn men are not simply essential to the population; they are vital to the colony’s day-to-day survival: from manning the longboats transporting supplies from passing ships to holding indispensable positions as firemen, postmaster, dentist, and minister.

All those involved in the proceedings came to realize that condemning any of these men to anything more than symbolic punishment would be tantamount to punishing the entire population of Pitcairn and effectively destroying the cultural heritage they’ve struggled for generations to perpetuate.


In October of 2004, six of the seven charged were found guilty of a variety of sexual assault offenses–from simple assault to rape:

Steve Christian, a 50-year-old descendant of Fletcher Christian, and his son Randy, were found guilty of 14 counts of rape and indecent assault.
Steve was sentenced to three years in Pitcairn Prison (but has yet to serve); Randy to six years.

Another Christian heir, Dennis Christian, postmaster, was convicted of one charge of indecent assault and two sexual assaults and sentenced to 300 hours of community service.

Len Brown (father-in-law of Steve Christian) was sentenced to two years of home detention; Len’s son, Dave, 400 hours’ community service.

Lastly, Carlyle Young, a descendant of Bounty midshipman Ned Youn, was sentenced to five years in Pitcairn Prison.

In 2007, two more defendants were found guilty of rape and indecent assault charges: Shawn Christian (another Christian descendant) and Brian Young (Ned Young descendant) were sentenced to three and a half years and six and a half years, respectively.

After serving two years of his sentence, Christian was released from prison and subsequently elected Mayor of Pitcairn, while Young’s sentence was reduced to house arrest after serving two years.

The current residents of Pitcairn Island (47 in number as of April 2021), come from four specific families, two of which descend from the original Bounty crew: the Christians and Warrens (Bounty members), the Youngs and Browns who were descendants of two sailors who subsequently shipwrecked there in the 1800s.

Despite severe scrutiny and world condemnation, life on Pitcairn Island goes as it always has.
A daily struggle to survive that they all seem more than willing to face.

Wednesday, July 5, 2023

The ocean is as important to the climate as the atmosphere

Finding out if amoc is going amok
image: Amanda kowalski

But only now is it beginning to be studied properly
 For homo sapiens, a dry-land species, discussions of the climate and how it is changing tend to revolve around what is going on in the atmosphere.
This is a dangerously parochial attitude, for the atmosphere is but one of two fluid systems circulating above Earth’s solid surface.
The other, the ocean, is in many ways the more important of the pair.

It is the circulation of the ocean which, by redistributing heat, limits the temperature difference between tropics and poles to about 30°C.
Were the atmosphere alone responsible for moving heat, that difference would be more like 110°C.
And, when it comes to anthropogenic global warming, the problem would be far greater without the ocean’s buffering effect.

Not only does the ocean absorb heat which would otherwise remain in the air, it also swallows a third of the carbon dioxide emitted by human activity.
Though that makes seawater more acid (or, strictly speaking, less alkaline), which may harm some marine species, much of the CO2 involved ends up in the abyss, where it can cause no greenhouse effect, and where it is likely to remain for many centuries.

The poverty of human understanding of ocean circulation, compared with that of the atmosphere, is therefore lamentable.
And the aaas meeting was treated to an excellent lamentation on the matter by Susan Lozier of the Georgia Institute of Technology, who was also last year’s president of the American Geophysical Union.

A simplified illustration of the global “conveyor belt” of ocean currents that transport heat around Earth. Red shows surface currents, and blue shows deep currents.
Deep water forms where the sea surface is the densest.
The background color shows sea-surface density.
Oceanographers worked out in the second half of the 20th century that the system’s engine room is in the North Atlantic.
Here, in a process called the Atlantic meridional overturning circulation (amoc), water moving up from the tropics cools, thus increasing in density, until it becomes so heavy that it starts to sink, pulling more water up from farther south to replace it.
Having descended as much as 3km, it then heads south itself.

Though some oceanic overturning of this sort goes on elsewhere, 90% of it happens in the North Atlantic.
And it is this North Atlantic overturning which drives what is often described as a planet-spanning conveyor belt of connected currents.

That, at least, is conventional thinking.
But Dr Lozier reckons it a bad analogy.
A conveyor belt conveys an image of smooth and linear progress.
This belt, though, jerks around all over the place, making it far harder to discover what is going on.

A smoothly moving belt need be examined only occasionally to check if its rate of progress is varying.
So when, in 2005, a paper in Nature reported, on the basis of the five pertinent shipborne surveys which had been made since 1957, a 30% drop in the volume of amoc between 1992 and 2004, there was serious concern.
If such a fall continued, it would change weather patterns, particularly in Europe, by altering planetary heat distribution.
It would also reduce the rate at which CO2was carried into the deep ocean.

As it happened, though, 2004 was a turning-point in observations of what is going on, for it saw the beginning of the deployment of a set of recording instruments which are now known as rapid amoc.
These monitor the Atlantic a couple of degrees north of the Tropic of Cancer, the part of the world where the surveys reported in the Nature paper had been conducted.
rapid amoc was joined in 2014 by an arctic counterpart, osnap, the Overturning in the Subpolar North Atlantic Programme.

The upshot has been the discovery that the rate of overturning can vary, apparently at random, as much as six-fold during the course of a year.
The fall described in the Nature paper was an artefact of an impoverished data set.

Another finding of osnap has been that the details of where overturning happens in the North Atlantic are not as models had predicted.
Most turnover, it turns out, occurs on the east side of the ocean, not the west, as previously believed.
Though this may not matter much in the grand scheme of climate change, it is a further example of how poorly people have understood what is going on at sea.

The next step for osnap is to extend its remit into looking at carbon dioxide uptake.
And more systematic studies are getting going in other parts of the ocean, too, as landlubbing humans are, at last, taking proper notice of the hitherto-neglected 71% of the surface of the planet they are pleased to call “Earth”, but which might, in truth, be better dubbed “Sea”.

Links :

Tuesday, July 4, 2023

British Isles & misc. (UKHO) layer update in the GeoGarage platform

Historic crossing of extreme swimmer Stève Stievenart in Catalina

Stève Stievenart before his departure on Tuesday evening.
(D. Michel/The Team)

From BreakingLatestNews

This seal is a “monster”.
A physical, mental and pugnacious monster.
After having hung the triple crown (La Manche, Manhattan and Catalina) and the double triple crown (“two way” of La Manche, two towers of Manhattan and “two way” Catalina) on his list, Stève Stievenart, known as Stève le phoque , signed a resounding feat this Friday in Los Angeles.
The extreme swimmer managed a great first: the “three way” of Catalina (32 km x 3), i.e.
three crossings between Catalina Island and Los Angeles, which represents more than 100 km in a single swimsuit bath, and in water that fluctuated between 16 and 19 degrees.

In January 2022, Stievenart completed a “one way” (Catalina – Los Angeles in 1:41 p.m.) before doing it again in June of the same year with a “two way” (LA – Catalina then Catalina – LA in 28:45).
A year later, Stève le Phoque has completed his “three way”, a historic performance because he is the first to accomplish it.
To complete these three crossings, he swam non-stop for 51 hours 18 minutes and 3 seconds, from Tuesday evening to Friday morning.

Accompanied by a team of around ten people (pilots, “spotters”, cooks, kayakers, not to mention his crew for assistance, particularly in refueling) aboard the boat Pacific Star, Stève Stievenart set off from Doctor Cove in Catalina Tuesday evening at 8:43 p.m., the body slathered with Vaseline (to fight against friction) and Sudocrem (against salt).
Shortly after his departure, when it was already dark, the kayaker who was at his side hit him hard on the back and on the head.

Santa Catalina with the GeoGarage platform (NOAA raster chart)

He suffered terribly from his back throughout the crossing, to the point of almost giving up once he arrived on a piece of sand from Palos Verdes to San Pedro, at the end of his first crossing (15 hours 35 minutes of swimming).
“I’m not going to be able to swim another 20 hours like this,” he breathed.
He almost stopped everything but he left anyway, head in the water and arms in motion.
It was then 12:25 p.m. local time on Wednesday (9:25 p.m. HF).

It was under the Californian sun while heading towards Catalina that a tribe of dolphins appeared in the middle of the afternoon.
In the evening, during a refueling – they take place every 30 minutes -, Stievenart complains of his back, which makes him suffer excruciatingly.
Again, he can’t help but continue his journey and ignore the pain as much as possible.
And it was a little before daybreak on Thursday morning, at 5:01 a.m., that he set foot on a small Catalina beach, in front of an imposing cliff (2nd crossing in 16 hours 42 minutes).

A ballet of dolphins and whales

He then just completed a “two way”.
He can stop there, but he got ready for a “three way” and leaves just as dry, after only one minute and twenty seconds.
“Los Angeles, here we go,” he says enthusiastically despite visibly very strong pain.
In the morning, a colony of dolphins is having fun in front of him, a welcome energy especially as a mola hangs around nearby, which has the gift of disturbing his concentration.
Her lips are burnt with salt.

If the sun is strong, the ocean is “glassy”, without wind.
Whales and dolphins are once again the kings of the spot.
They improvise an impressive ballet in front of the swimmer who continues his quest for this unprecedented “three way” by working to grind his arms as much as possible.
While the coast of Los Angeles is in sight, a strong side wind begins to blow and the current also becomes quite a handicap.
The swimmer from Pas-de-Calais is only advancing very slowly, also exhausted by a monumental effort, at this time of 48 hours.

The end is endless.
In the dark and faced with unfavorable conditions, he tried as best he could to advance, this time towards Cabrillo beach a little further south of Palos Verdes, near the port of Long Beach.
It is surrounded by two kayakers that Stievenart finally ends up reaching dry land.

In bad shape, he still manages to stay upright and validate this famous “three way” – 18 hours and 59 minutes for the 3rd portion.
It is then 12:01 a.m. this Friday.
“I am very happy to have come to the end of this three way, and I thank for my team, because without them it is obvious that I would never have been able to accomplish this”, he confided.
His triple crossing (51h28’03) is a resounding feat in the world of open water swimming.
Simply out of the ordinary.

Links :

Monday, July 3, 2023

The last 96 hours of the Titan tragedy

Video shows wreckage of Titan sub brought ashore
courtesy of BBC
From Wired by Alex Christian

OceanGate’s lost sub sparked a frantic rescue effort—and resurfaced safety questions that had been raised years earlier.

It would take two and a half hours for Titan and its crew to drop the 13,000 feet to the bottom of the ocean.
Having clambered into the submersible’s cramped confines, the pilot and four passengers sat awkwardly against the inside of the hull, engineers bolting the craft closed from the outside.
From now until the end of their dive, the five of them would be encapsulated, separated completely from the world’s water and air.

They had departed from the Canadian port city of St. John’s, Newfoundland, at 8 am Eastern Daylight Time on June 18, 2023.
Now, roughly 375 nautical miles to the east, they were poised to begin their mission: to dive to the Titanic.
Riding in the sub were Stockton Rush, president and founder of OceanGate, the exploration company that operated the craft; British billionaire Hamish Harding; French deep-sea explorer Paul-Henri Nargeolet; and British-Pakistani businessman Shahzada Dawood and his son Suleman.

Via a floating platform, they and their craft moved down from the mothership, the Canadian research icebreaker Polar Prince, into the choppy waters of the North Atlantic.
The white, tubelike outline of the sub quickly disappeared beneath the waves, beginning its slow descent through the dark ocean depths to the world’s most famous shipwreck.

One hour and 45 minutes later, communications with Titan were lost.
If their vessel was still intact, regardless of where they were, the crew would run out oxygen in approximately 94 hours.
An international search-and-rescue operation, set desperately against the clock, was soon to begin.

By the morning of June 19, the rescue mission was fully underway.
The US Coast Guard had started conducting a search 900 miles east of Cape Cod, in collaboration with the Canadian armed forces and commercial vessels in the area.
“It is a remote area and a challenge, but we are deploying all available assets to make sure we can locate the craft,” Coast Guard rear admiral John W. Mauger said in a press conference.

Already, time was against them.
When doing dives way out into the ocean, a OceanGate was, “you’re roughly a half-week to a week out from help,” says Peter Girguis, an oceanographer at Harvard University.
And, confusingly, it had taken the crew aboard the Polar Prince nearly eight hours to alert the US Coast Guard that Titan had gone missing.
Not only were the US and Canadian authorities tasked with locating a 22-foot-long submersible in an area twice the size of Connecticut, with waters two and a half miles deep, but by the time of Mauger’s press conference, the sub had approximately 63 hours of oxygen left.

There were further complications.
Titan lacked an emergency radio beacon or a dedicated recovery system.
“There wasn’t any way for its surface vessel to send anything down, help locate the sub, or pull them up,” says Girguis.
And without a beacon, Titan could be floating on the surface unnoticed.

But the greatest concern was the craft’s structure.
Unlike most submersibles, which have a spherical pressure hull made from steel or titanium, Titan was an experimental carbon-fiber vessel.
Going dark could mean its hull had been compromised.
It could mean the craft would be fragile during recovery.
It could mean it had failed altogether.

With seemingly little information to work with, the search teams split their efforts between the surface and the ocean’s depths.
Alongside US and Canadian authorities, commercial deep-sea firms, private vessels, military planes, and a submarine had joined the hunt by June 20.
Ships and planes scoured the surface visually for signs of the sub’s white hull.
Beneath the waves, rescue ships pinged the ocean with sonar in the hope of detecting the craft, with acoustics experts drafted in to analyze underwater noises.

Because of the lack of a recovery system aboard the Polar Prince, France’s sea ministry diverted its Atalante vessel—equipped with a subsea remote-operated vehicle—to assist with the operation.
With its deep-diving capabilities and remote controlled cutting arms, the ROV could, if it found the sub, try to free it from any entanglements and help bring it to the surface.
But for now, the Atalante was still a day away.

Time Running Out

On June 21, the search parties confirmed they had their first lead.
Rescuers divulged that surveillance vessels had detected underwater sounds at 30-minute intervals for two straight days.
Periodic banging is a tactic taught to stranded submariners to assist rescue searches, and experts hypothesized that Nargeolet, formerly a diver with the French navy, would know this.
“This is a search-and-rescue mission, 100 percent,” said Captain Jamie Frederick of the First Coast Guard District, dismissing the idea that the crew had already perished and that recovery of the sub was the aim.
“We’ll continue to put every available asset that we have in an effort to find the Titan and the crew members.”

As the day progressed, five surface vessels were searching for Titan, with two ROVs searching in the ocean.
More underwater robot vehicles were due to arrive on the morning of June 22.
But they were desperately late to join the hunt.
“Authorities had to airlift them to Newfoundland,” says Girguis.
“They had to then place them on ships and sail them out before they could even begin searching underwater.” By the point that the underwater search of the seabed had truly gathered momentum, with the ROVs crisscrossing the ocean floor systematically to comb for the Titan, less than 12 hours of oxygen would be left on the sub.

A special naval salvage system, designed to lift up to 27 tons of machinery out of the water, also arrived in St.
John’s on June 21—but it needed an additional 24 hours to be prepped for use.
“We just don’t have the means to deploy a huge arsenal of rescue equipment, because it can only get there by ship, ultimately,” says Girguis.
Whether the salvage system would take part in any rescue now rested on a knife edge.
It was estimated that Titan would run out of oxygen at around 7 am Eastern time on June 22.

But quickly, that question became moot—by 11:45 am Eastern time June 22, the search was over.
The US Coast Guard announced that an ROV launched from the offshore vessel Horizon Arctic, which had arrived at the search site the night before, had found remains from the Titan 1,600 feet from the bow of the Titanic on the seafloor, some 12,500 feet deep.
The first piece of debris discovered was the vessel’s nose cone—part of a large debris field containing the front end of the pressure hull.
“The debris is consistent with the catastrophic loss of the pressure chamber,” said Mauger.

“We now believe that our CEO Stockton Rush, Shahzada Dawood and his son Suleman Dawood, Hamish Harding, and Paul-Henri Nargeolet have sadly been lost,” OceanGate said in a statement.
“These men were true explorers who shared a distinct spirit of adventure and a deep passion for exploring and protecting the world’s oceans.”

While many entrepreneurs see space as the next frontier, Stockton Rush believed adventure lay at the bottom of the ocean.

“Must-Do Dive”

Rush had a long background in aerospace and aviation.
According to his website’s biography, he became the youngest jet-transport-rated pilot in the world at age 19, before becoming a test-flight engineer for the McDonnell Douglas F-15 fighter jet program in 1984.
Over the following 20 years, his business ventures included serving on the board of Seattle sonar technology firm BlueView Technologies, as well as being chairman of wireless-remote-control-device manufacturer Remote Control Technology in Washington.

But rather than the skies, Rush looked to the deep sea when he founded OceanGate alongside Argentine American businessman Guillermo Söhnlein in Everett, Washington, in 2009.
“The ocean is a scary thing,” Rush told the BBC in 2022.
“And because of that, what I have wanted to do with this business was just move the needle and get people excited about the ocean, explore it, and discover what was out there.”

Although OceanGate’s mission was to explore the deep ocean and to enable easier access for scientists, researchers, and wealthy tourists, Rush had one 15-mile-square site as his primary goal: the watery graveyard of the Titanic.
“People are so enthralled with the Titanic that it became a must-do dive,” he told the BBC.
“There are three words in the English language that are known throughout the planet: Coca-Cola, God, and Titanic.”

Rush believed advances in materials science meant a new type of submersible could be created that was lighter, roomier, and more cost-efficient than industry-standard deep-sea vessels, which tended to be spherical and made completely out of metal.
These, while effective, had their limits.
“If you want to fit more than two or three people into a steel-titanium sphere, you have to build a submersible the size of the Death Star,” says Sal Mercogliano, a maritime historian and professor at Campbell University in North Carolina.
“So, the next evolution was a new hull form.”

OceanGate’s first prototype, Cyclops 1, launched in 2015.
(Söhnlein left the company in 2013 once it transitioned to its engineering phase.) 
A five-person submersible capable of reaching 500-meter depths, Cyclops 1 served dozens of research projects, expeditions, and training dives, including a September 2018 expedition that Rush piloted to Washington’s San Juan Islands alongside researchers and scientists.
Many of its design cues were implemented in Titan, such as an automated control system that monitored oxygen, power management, navigation, and other critical system diagnostics, and commercial off-the-shelf technology—exterior 4K cameras, a laser scanner, and a large digital display on which to view the Titanic wreckage.

However, Cyclops 1 was made with a steel hull.
OceanGate’s Titan submersible, designed to take five people down to depths of just over 13,000 feet, was built with a carbon-fiber pressure hull, capped on each end by a titanium dome.
In 2021, OceanGate commenced its first dive to the Titanic aboard the Titan, this being the deepest that a carbon-based vessel had ever carried passengers before.

That mission was a success—but concerns over Titan’s safety had been raised long before its final, doomed expedition to the Titanic in June 2023.
As the rescue mission proceeded, these returned to the fore.
Red Flags

In 2018, David Lochridge, OceanGate’s director of marine operations, was fired after raising concerns about Titan’s experimental carbon-fiber hull before its maiden voyage.
In a subsequent lawsuit over his dismissal, he wrote that the hull could subject passengers to “potential extreme danger.” He noted that he had seen visible flaws in the hull’s carbon fiber.
These, he argued, could develop into larger tears after multiple dives, raising the risk of the hull failing.

OceanGate had a solution.
It had developed an acoustic monitoring system to listen for sounds of the carbon-fiber hull failing.
If these tell-tale sounds were detected during a dive, the system would alert the sub to return to the surface.
Lochridge was unconvinced.
“This type of acoustic analysis would only show when a component is about to fail—often milliseconds before an implosion—and would not detect any existing flaws prior to putting pressure onto the hull,” he said in his wrongful-termination claim.

At a 2022 speech at a Seattle tech conference, Rush described how various submarine safety programs were “over the top in their rules and regulations.” 
In his view, OceanGate was pioneering groundbreaking new technology, and deviating from the accepted norms of the industry was part of that process.
“If you’re not breaking things, you’re not innovating.
If you’re operating within a known environment, as most submersible manufacturers do, they don’t break things.”

In building a first-of-its-kind submersible with a carbon-fiber hull, Rush wasn’t following the naval engineering rule book.
“It’s an atypical design,” explains Jennifer Waters, a naval architect and ocean engineer at State University of New York Maritime College.
“Keeping people alive in the ocean depths, at extraordinarily high amounts of pressure, is no trivial matter.
That’s why the strongest shape for a pressure hull is spherical, and why steel and titanium is typically used—most other materials tend to get brittle over time.”

Waters says brittle fractures can occur in carbon fiber that’s exposed to repeated pressurizations.
Over multiple dives, these recurring stresses, strains, stress intensities, and exposures to high and low temperatures—a process known as cyclic loading—creates fatigue.
Compared to a steel or titanium hull that may bend over time, indicating that repair is required, carbon fiber breaks.
“And that’s dangerous,” she adds.
“When a structure made from brittle materials fails, it tends to be catastrophic.
It may not be the first dive, but it could be the hundredth.
And that’s why you need nondestructive testing to check its integrity.”

In the court documents, Lochridge alleges that this is exactly the sort of testing that he called for but that OceanGate refused to conduct it on the experimental design of the hull, instead choosing to rely on its in-house acoustic monitoring system.
Furthermore, Titan wasn’t industry-certified: a 2018 letter from professional trade group the Marine Technology Society (MTS) red-flagged OceanGate’s marketing materials in which the company claimed its submersible would, nevertheless, meet or exceed a certification called DNV-GL.
Issued by independent Norwegian foundation Det Norske Veritas (DNV), the certification is considered the gold standard for marine equipment.

But MTS noted: “It does not appear that OceanGate has the intention of following DNV-GL class rules.” Saying that the craft would nevertheless pass such standards would be “misleading to the public and breaches an industrywide professional code of conduct we all endeavor to uphold,” the letter added.

Past passengers also shared details of problems with Titan.
During a test trip on board the craft off the coast of the Bahamas in April 2019, Karl Stanley, a submersibles expert, flagged loud cracking sounds that indicated pressure was crushing a defect in the hull.
Rush subsequently altered Titan, built a new hull, and postponed expeditions.
But since Titan’s maiden voyage in 2021, those on board have detailed communication, navigation, and buoyancy issues during their 12-hour round trips to the Titanic.

Mercogliano suggests that these previous issues could explain why it took eight hours for the crew of the Polar Prince to notify the US Coast Guard that Titan was missing.
“The sub had lost communications before,” he says.
“So, they may not have assumed there was a disaster at all.”

Because Titan dived in international waters, OceanGate was essentially allowed to operate without regulations, says Mercogliano.
“There’s no real international standard when it comes to submersibles, he says.
“There was ultimately no regulatory body that could act upon people’s concerns.”
OceanGate and DNV didn’t respond to WIRED’s requests for comment.
MTS declined to comment.

Experts say there were additional issues with Titan beyond its experimental hull.
Girguis points to its surface escape hatch being unusually bolted from the outside; the lack of an independently powered recovery system that could have been deployed from its surface vessel; and the sub using text-based communications with its mothership, as opposed to industry-standard acoustic beacons.
“If Titan had the full array of beacons, safety measures, and a robust communications system, all that information would have helped authorities understand the situation better—and potentially save the submersible,” he says.

Titan’s minimalist interior and seemingly improvised, off-the-shelf components have also drawn scrutiny, particularly the modified Logitech F710 game controller that was used to pilot the vessel.
“The minimalist design is arguably what you want from a submersible: simplicity and robustness,” says Girguis.
“However, submersibles rely heavily on mechanical and electromechanical controls, which is why most have a bank of switches, so the pilot has direct control—rather than a computer that might crash.
So, a game controller and graphical interface may be simple to operate, but they’re certainly not robust.”

Submersible disasters are extremely rare—and vessels are built to last.
Girguis cites the Alvin: Commissioned in 1964, the deep-ocean research submersible was the first crewed vessel to explore the Titanic wreckage, in 1986.
It’s still in operation, having made more than 5,000 dives.
“I feel safer in a research submersible than I do on the highway,” says Girguis, who estimates he has done more than 100 deep-sea research dives into the Pacific Ocean and the Gulf of Mexico.
“Research submersibles have been diving for half a century—and they’ve never budged from being safety-first.”

Girguis says some research submersibles are able to complete 150 dives a year.
Titan, however, was only on its 14th voyage on June 18.
Unanswered Questions

After Titan’s debris was found, the US Navy revealed that it had detected an acoustic signature consistent with an implosion on June 18, in the general area where the vessel was diving and lost communication with Polar Prince.
Although that information was relayed to on-scene commanders leading the search effort, the sound of the possible implosion wasn’t determined as definitive, and so the search-and-rescue mission was launched.

An investigation, led by the US Coast Guard, is underway.
The Transportation Safety Board of Canada, as well as French and British maritime agencies, have joined the inquiry.
So far, five major pieces of Titan have been found 12,467 feet below the ocean’s surface and are now being brought to shore.
Among the debris, the Coast Guard says it may have also recovered human remains.

Jai Sharma, maritime solicitor at law firm Clyde & Co, says the investigation will be detailed and lengthy.
Once complete, it will be able to recommend civil or criminal charges.
“In this case, you have the passengers’ families that come from wealth and have suffered devastating losses, so there could be big claims in civil court,” he says.

Complicating the question of liability is that the incident occurred in international waters.
OceanGate’s waiver, which all passengers signed before the dive, states that any disputes would be governed by the laws of the Bahamas, where the company is registered—its legal system is based on English Common Law.
However, it’s unclear if the case will eventually be heard in the Bahamas, in the US, or Canada, where the Polar Prince was registered.

OceanGate was the sole tourist operator providing trips to see the Titanic.
On its website, it invited passengers to “follow in Jacques Cousteau’s footsteps and become an underwater explorer.” It largely catered to high-net-worth individuals: seats on its final, ill-fated trip cost $250,000 per person.
It’s part of an extreme tourism industry that’s niche but growing.
“Although it’s a small proportion of the broader adventure tourism market, these sorts of experiential trips and expeditions to the furthest regions are growing in demand,” says John Lennon, a tourism professor at Glasgow Caledonian University.

Although OceanGate may be an outlier in that it ignored industry standards, these sorts of adventures naturally work in the business of risk, adds Lennon.
“People are increasingly chasing extreme adventures.
There seems to be a craving for extraordinary and unusual expeditions that perhaps don’t have a long track record of rescuing people—that may even be part of the motivation to go.” As people continue to look for limits to push, and companies look for new ways to make money, there is a danger that the Titan and OceanGate story isn’t a one-off.

“When I learned the submersible was missing, I was asking questions like, did they turn on the emergency beacon? Was there an underwater beacon?” says Girguis.
“As I learned more about Titan, I went through its list of safety features and found them all wanting, down to the haphazard approach in assembling and operating the vessel,” he adds.
“It was a tragedy that was utterly avoidable.”

Links :

Sunday, July 2, 2023

South Pacific | Mother Nature tries to create an island before your very eyes

Wanna see how a new island is made?
Check out this fantastic show Mother Nature has put on in the middle of the Pacific Ocean in the Solomon Islands.
Watch the Kavachi undersea volcano as it erupts underwater.
Will it finally make island status?
Localization with the GeoGarage platform (NGA nautical raster chart)
Not yet on the SB409157 ENC (depth 6.5 m)