Saturday, June 12, 2021

The 2021 submarine cable map


This new edition depicts 464 cable systems and 1,245 landing stations that are currently active or under construction.

From GoogleMapsMania by Keir Clarke

Every year Telegeography releases a new map of the huge global network of undersea telecommunication cables which carry all our data around the world.
The 2021 Submarine Cable Map has now been published.

Subsea cables carry telecommunication signals under the oceans, communicating information between different countries and regions of the world. In the 19th Century the first submarine cables were laid to carry telegraphy traffic.
In the 21st Century submarine cables carry digital data, which includes telephone and Internet data.

The new submarine cable map from Telegeography shows 464 cables and 1,245 landing stations.
This year's map also features lots of textual information, featuring both cable trivia and answers to FAQ's about cable suppliers, content providers, fiber etc.
For example - did you know that there are now over 1.3 kilometers of underwater cables around the world (if they were laid end-to-end they could wrap around the world 30 times). 

The Submarine Cables of the World
with the Principal Connecting Land Lines and the Sea Coast Stations
(1893)
 
Every year's edition of the Telegeography Submarine Cable Map has a different design.
You can explore Telegeography's Submarine Cable Maps for previous years by changing the year in the map's URL. For example, one of my favorite Telegeography maps can be found at http://submarine-cable-map-2015.telegeography.com/.
This 2015 map was inspired by medieval and renaissance cartography and features a vintage map style containing sea monsters, cartouches and border illustrations.
 
Links :

Friday, June 11, 2021

There’s a new ocean now—can you name all 5?

The Gerlache Strait lies off the west coast of the Antarctic Peninsula, in the large band of ocean around Antarctica that has been reclassified as the Southern Ocean by National Geographic cartographers. The strait would once have been considered part of the Pacific.
photo by Jasper Doest, Nat Geo Image collection

From National Geographic by Sarah Gibbens 

On World Oceans Day, Nat Geo cartographers say the swift current circling Antarctica keeps the waters there distinct and worthy of their own name: the Southern Ocean.

Those familiar with the Southern Ocean, the body of water encircling Antarctica, know it’s unlike any other.

“Anyone who has been there will struggle to explain what's so mesmerizing about it, but they'll all agree that the glaciers are bluer, the air colder, the mountains more intimidating, and the landscapes more captivating than anywhere else you can go,” says Seth Sykora-Bodie, a marine scientist at the National Oceanic and Atmospheric Administration (NOAA) and a National Geographic Explorer.
 

 Ocean circulation defines the Southern Ocean.
 
Since National Geographic began making maps in 1915, it has recognized four oceans: the Atlantic, Pacific, Indian, and Arctic Oceans.
Starting on June 8, World Oceans Day, it will recognize the Southern Ocean as the world’s fifth ocean.

“The Southern Ocean has long been recognized by scientists, but because there was never agreement internationally, we never officially recognized it,” says National Geographic Society Geographer Alex Tait.

South Pole
Matthew W. Chwastyk, and Soren Walljasper, NGM Staff. Eric Knight
Sources: NASA/JPL; Green Marble


Geographers debated whether the waters around Antarctica had enough unique characteristics to deserve their own name, or whether they were simply cold, southern extensions of the Pacific, Atlantic, and Indian Oceans.


“It’s sort of geographic nerdiness in some ways,” Tait says.
He and the National Geographic Society’s map policy committee had been considering the change for years, watching as scientists and the press increasingly used the term Southern Ocean.

The change, he adds, aligns with the Society’s initiative to conserve the world’s oceans, focusing public awareness onto a region in particular need of a conservation spotlight.

“We’ve always labeled it, but we labeled it slightly differently [than other oceans],” Tait says.
“This change was taking the last step and saying we want to recognize it because of its ecological separation.”

Marine biologist and National Geographic Explorer at Large Sylvia Earle praised the cartographic update.

“While there is but one interconnected ocean, bravo to National Geographic for officially recognizing the body of water surrounding Antarctica as the Southern Ocean,” Earle wrote in an e-mailed statement.
“Rimmed by the formidably swift Antarctic Circumpolar Current, it is the only ocean to touch three others and to completely embrace a continent rather than being embraced by them.”

Limits of the Southern Ocean
National Geographic now recognizes five world oceans.
Most of the waters that surround Antarctica out to 60 degrees south latitude, excluding the Drake Passage and Scotia Sea, constitute the newly acknowledged Southern Ocean.

Matthew W. Chwastyk and Greg Ugiansky, NG Staff
Sources: NASA/JPL; International Hydrographic Organization (IHO)


An ocean defined by its current

While the other oceans are defined by the continents that fence them in, the Southern Ocean is defined by a current.

Scientists estimate that the Antarctic Circumpolar Current (ACC)  was established roughly 34 million years ago, when Antarctica separated from South America.
That allowed for the unimpeded flow of water around the bottom of the Earth.

The ACC flows from west to east around Antarctica, in a broad fluctuating band roughly centered around a latitude of 60 degrees south—the line that is now defined as the northern boundary of the Southern Ocean.
Inside the ACC, the waters are colder and slightly less salty than ocean waters to the north.

Extending from the surface to the ocean floor, the ACC transports more water than any other ocean current.
It pulls in waters from the Atlantic, Pacific, and Indian Oceans, helping drive a global circulation system known as the conveyor belt, which transports heat around the planet.
Cold, dense water that sinks to the ocean floor off Antarctica also helps store carbon in the deep ocean.
In both those ways, the Southern Ocean has a crucial impact on Earth’s climate.

Scientists are currently studying how human-driven climate change is altering the Southern Ocean.
Ocean water moving through the ACC is warming, scientists have learned, but it’s unclear how much this is impacting Antarctica.
Some of the most rapid melting of the continents ice sheets and shelves have been where the ACC is closest to land.

(Read more about how climate change is affecting the ocean’s conveyor belt.)

An environment like no other

For now, by fencing in the frigid southern waters, the ACC helps keep Antarctica cold and the Southern Ocean ecologically distinct.
Thousands of species live there and nowhere else.

The Southern Ocean “encompasses unique and fragile marine ecosystems that are home to wonderful marine life such as whales, penguins, and seals,” notes National Geographic Explorer in Residence Enric Sala.

What’s more, the Southern Ocean has ecological effects elsewhere as well.
Humpback whales, for example, feed on krill off Antarctica and migrate far north to winter in very different ecosystems off South and Central America.
Some seabirds migrate in and out too.

By drawing attention to the Southern Ocean, the National Geographic Society hopes to promote its conservation.

The impacts of industrial fishing on species like krill and Patagonian toothfish (which is marketed as Chilean sea bass) has been a concern in the Southern Ocean for decades.
In 1982, catch limits were imposed in the region.
The largest marine protected area (MPA) in the world was established in the Ross Sea off West Antarctica in 2016.  A number of organizations are working to set aside more MPAs to protect the Southern Ocean’s most critical feeding grounds, for example off the Antarctic Peninsula.

“Many nations across the world support the protection of some of these areas from industrial fishing,” Sala says.

Mapping the world as it is

Since the late 1970s, the National Geographic Society has employed a geographer who oversees changes and tweaks to every map that’s published.
Tait has been on the job since 2016.

He says he takes a journalist’s approach to the process.
It involves staying on top of current events and monitoring who controls what areas of the world.

“It is important to note it’s a map policy, not a policy about Nat Geo’s position on [geopolitical] disputes,” he says.
For example, National Geographic maps show that the U.K. controls the Falkland Islands, even though Argentina claims them too.
In disputed areas, Tait works with a team of geographers and editors to determine what most accurately represents a given region.

Minor changes happen on a weekly or biweekly basis.
Major changes, like labeling the Southern Ocean, are more rare.

Generally, National Geographic has followed the International Hydrographic Organization (IHO) on marine names.
While not directly responsible for determining them, the IHO works with the United Nations Group of Experts on Geographical Names to standardize names on an international scale.
The IHO recognized the Southern Ocean in its 1937 guidelines but repealed that designation in 1953, citing controversy.
It has deliberated on the matter since, but has yet to receive full agreement from its members to reinstate the Southern Ocean.

The U.S. Board on Geographic Names, however, has used the name since 1999.
And in February of this year, NOAA officially recognized the Southern Ocean as distinct.

Tait says National Geographic’s new policy will have an impact on how children using maps in school learn to see the world.

“I think one of the biggest impacts is through education,” he says.
“Students learn information about the ocean world through what oceans you’re studying.
If you don’t include the Southern Ocean then you don’t learn the specifics of it and how important it is.”

Links :

Thursday, June 10, 2021

Pacific and Atlantic Oceans: where the legend of Cape Horn is born

Where the Pacific and Atlantic Oceans meet, the legend of Cape Horn is born

From Sail World by Global Solo

Cape Horn, Cabo de Hornos, whatever you want to call it, is a mythical place where the Pacific and Atlantic Oceans meet.
To the detriment of the name, it is an island part of the Tierra del Fuego archipelago that evokes images of pure and wild nature.
Right where the Pacific and Atlantic Oceans meet, our imagination is free and flies.
 
Leave “The Antarctic Region” and the “Ice Limit” to starboard!
 
Graceful and elegant, albatrosses brave the storms and winds of the screaming fifties between the Pacific and Atlantic Oceans.
Continuous perturbations travelling clockwise around Antarctica push huge bodies of water towards the Drake Strait.
Cape Horn and Antarctica create an obligatory passage for wind and sea, exposing all the power of nature.

The very strong howling wind swings at every cold front from North-West to South-West.
The winds of the warm sector of the depression blow regularly and very strong for days, raising huge waves.
As the cold front passes, conditions become furious.
The wind shifts and blows cold, angry, straight from Antarctica, bringing with it waves from a different direction.
This is the most dangerous moment, the wave patterns cross and sum up creating a confused, difficult, foolish sea.
Many navigators have tasted the icy bites of freeze cold water, the lethal breakers.
Where the Pacific and Atlantic Oceans meet, you can experience pure nature, but you can also die.


Cape Horn - Cold Front - 42 hours from impact - photo © Global Solo Challenge

Forty-two hours to impact - the tension in the air before Cape Horn


We were sailing 60 degrees south, further south than we would have liked to go, but the weather forced us to do so.
I was worried about the drop in the temperature of the water, which was then below four degrees Celsius.
It was clear that we were ??
icebergs territory, some had already been reported to us north of us, above 59 degrees of latitude.
We were in the warm sector of a very deep depression, a real storm of the type that had fascinated me since I was a child.
The depression was reaching us from West to East as we continued our mad flight for Cape Horn.
It was February 2012, there were two of us on a racing Class40 during the 2011/2012 Global Ocean Race.
Headed to where our dreams had an appointment with the Pacific and Atlantic Oceans.

At that moment we had temporarily taken the lead of the race, for the first time since the start.
Our dive south had paid off but the tension on board continued to rise.
With each update of the synoptic chart data, the situation seemed to get worse.
We were in contact with the other competitors and the race committee and even the Chilean coast guard had been alerted.
We were located 420 miles from Cape Horn, and even with reduced sails in the storm we still held an average of 10 knots.
We would arrive to round the cape after about forty-two hours, for our rendezvous between the Pacific and Atlantic Oceans.


Pacific and Atlantic Ocean – In navigation - photo © Global Solo Challenge

Cape Horn, where the sea goes crazy, the wind pushes you onto a lee shore

Our analysis, could not ignore an important fact, the dreaded cold front still far away but was pressing on us.
As we sailed, the depression and its associated cold front, travelled eastward much faster than us, shortening the distances between us and the cold front.
Every three hours with the satellite I downloaded new data but the response was inexorably the same.
The cold front would have reached us just about after 42 hours.
As cold front would pass, the wind would turn suddenly and violently from North-West to South-West.
Right where the Pacific and Atlantic Oceans meet and decide who to let pass.

Our far was multiplied by many worries related to the dangers that we might encounter.
Navigation between the Pacific and Atlantic Oceans is complicated by many factors.
In the warm sector of the depression, the February wind temperature is still tolerable, around ten degrees Celsius.
However, with the water around us at less than four degrees and the wind rising above fifty knots, the it was bitterly cold.

In those north westerly winds, we had nothing to worry about in relation to the continent or the archipelago of Tierra del Fuego.
In fact, if things deteriorated further, as long as the winds stayed from the North West we could have hove-to or even found some relative shelter from wind and sea closer to shore.
This, however only held true before the cold front, when you have free waters to run, if need be, all the way to Antarctica in the passage between the Pacific and Atlantic Oceans.
If the cold front had reached us, we'd suddenly find ourselves in lee shore at the worst possible time.


The storm - photo © Global Solo Challenge

A matter of hours - the meeting between the Pacific and Atlantic Oceans

Everything would have been different if we had arrived where the Pacific and Atlantic Oceans meet with even just a few hours of delay.
We would have found ourselves already close to the Chilean cliffs ending up in a very dangerous trap.
At the passage of the front a very strong wind from the South West would have arrived, straight towards land.
If the conditions had worsened we would have had to try sail away from shore, but without any space to run and to reduce apparent wind.
Neither of us onboard had ever faced similar conditions, The wind had been sustained for dozens of hours and the forecast was for a strong deterioration.
We did not know what awaited us at the meeting between the Pacific and Atlantic Oceans.

One last aspect disturbed us more than anything else, the orography of the ocean floor just where the Pacific and Atlantic Oceans meet.
Where we sailed the sea was majestic, with waves measured by the models between eight and twelve meters high.
But their period was very long, as during the whole navigation in the Pacific Ocean.
At the tip of a wave you felt like you were on a mountain looking at valleys.
On the bottom between two waves one perceived only the insignificant smallness of man in the face of the power of nature.
Not far in front of us however, the ocean floor rises from thousands of meters to less than 100 meters near Cape Horn.
This sudden rise, just like on the banks of Newfoundland and in the Bay of Biscay, drives the sea state crazy, where the continental shelf begins.


Pacific and Atlantic Oceans – Preparations for the storm - photo © Global Solo Challenge

Getting to Cape Horn at the worst time

Everything seemed lined up for us to arrive at the worst possible moment where the Pacific and Atlantic Oceans meet at Cape Horn.
We would have arrived at the time of the passage of the cold front, with a crossed sea, wave patters summing up.
The waves pushed by the rising currents of the sea from the abysses stand out madly as steep as walls.
If we had managed to round the cape before the cold front we could then have headed north during the worst from the southwest.
We would have avoided the Strait of Le Maire by going east of Isla de los Estados and heading for the Falklands.
We would have pulled out of the fury of the Pacific and Atlantic Oceans that meet, protected by Tierra del Fuego and the continent.

Returning to the Atlantic and heading north was all we wanted to do.
Finally leave behind us that damned point where the Pacific and Atlantic Oceans meet.
But we could not ignore the fact that we were playing on cat and mouse with the passage of the cold front.
If the depression accelerated even a little, we could have encountered life-threatening conditions.
We adjusted the sails to do our best despite the conditions.
Not being able to slow down the pressing depression we could only try to go faster.
The wind was picking up, the barometer had plummeted, and everything indicated that the storm would only get worse.
It is difficult to imagine that everything can become "much more difficult" when the wind is already blowing regularly above fifty knots.


Pacific and Atlantic Ocean – Hugo Ramon - photo © Global Solo Challenge

A difficult decision - the weight of responsibility

We were moving inexorably towards our rendezvous between the Pacific and Atlantic Oceans.
We didn't talk much, there wasn't much to say, apprehension was palpable in the air.
Neither of us wanted to speak out first and declare their fear.
I was sailing with Hugo Ramon, a professional sailor from Palma de Mallorca.
Neither had ever seen anything like this, neither could speak from experience.
Hugo, in that difficult situation, was extremely correct with respect to his role.
He told me that any decision I made he would support without discussion.
I was the skipper, the captain, it was up to me to decide, to preserve the first place or to think about safety.

We were quickly reducing the distances from the damned point where the Pacific and Atlantic Oceans meet.
Less than a day of navigation to go and the point of no return was given by the decision of whether to step onto the continental shelf or not.
Once we "climbed" onto the continental shelf, even if still at sea, our options would be dramatically reduced.
We were heading for the Diego Ramirez islands right on our route to Cape Horn.
In truth, these small islands represent the outpost of the American continent.
They are located right on the edge of the area where the seabed rises, we had to decide before going beyond them.


Pacific and Atlantic Oceans - Fatigue during the storm - photo © Global Solo Challenge

Continue to win - stop to save yourself

In that leg that would take us between the Pacific and Atlantic Oceans, two professional teams had already retired.
In an agitated satellite phone call with Miranda Merron of Campagne de France, I could hear her confusedly.
The sound of the sea was deafening, she just repeated "These boats can't do it".
This had happened several days before and the most experienced teams, including Ross and Cambell Field turned back for New Zealand the storms we encountered then.
Her words echoed in my thoughts, what if we were too late? Were this boats not safe enough for those waters? What if we had arrived between the Pacific and Atlantic Oceans right at the crossing of the front? What if the waves crossed and projected onto the shallow water and overwhelmed us? After all, we were sailing on a 12-meter boat that weighed just 4500 kilos.
A racing shell that was not indestructible nor invincible.

To sign up for the race we had to demonstrate, in sheltered waters, that in case of overturning we could self-right the boat.
In fact, these large and powerful boats remain stable even upside down.
In most cases, during an involuntary inversion, you typically dismast.
And, in fact, during our simulation we did the test without the mast.
The very fact that that test was required to participate made the possibility of an inversion far from remote.
From shore race director Josh Hall kept us updated constantly, but avoided making judgements.
This is because without being on the boat it is not possible to make an assessment of the situation.
Certainly from his words transpired all the worry of those who were following us from home.


4 reefs in the main and storm jib ahead of Cape Horn - photo © Global Solo Challenge

A sudden slap before Cape Horn

I still distinctly remember, almost ten years later, when, during the night, the boat was overwhelmed by a breaking wave.
The wave came from the South, we could have called it an anomalous wave, but we could see it as the first sign of what we could have faced.
The point of no return was approaching but that wave hit us with such violence as to shake the rigging boat and our souls.
We were scared, if that was a warning, and it had worked.
I called Hugo, I didn't even have to speak, he knew exactly what I had decided.
After a couple of hours it was dawn and with the help of the morning light we went out on deck to get ready to heave-to.
A manoeuvre where the boat stops, or at least slows significantly, and remains floating lulled by the immense waves.

The success of that manoeuvre was not to be taken for granted either, racing boats are very light and do not heave-to very well.
We had to do several tests before stabilising the boat, but to our surprise everything calmed down.
The motion was gentle as we ascended and descended from the huge mountains of the South Pacific.
We had hoisted the storm jib and took four reefs, which our mainsail was equipped with.
We had two handkerchiefs, but the boat remained stable, she only drifted sideways at two or three knots of speed.

Let the worst pass

The sense of relief at the decision was immense, we found ourselves laughing and patting ourselves on the back.
We were tempted to get back on course but we knew that overall that was the right decision.
Our direct competitors, with a newer boat, were back in the lead and forty miles ahead of us.
Miles that translated into at least four hours of advantage with respect to the passage of the front.
They had managed to recover precious time and decided to go straight, counting on rounding the Horn with a little margin ahead of the front and wind shift.

For us, however, the calculations indicated that we would not make it.
That rogue wave had only reminded us of the decision that had been weighing in the air for some time.
We hove-to for less than twelve hours waiting for the cold front to arrive, as the hours passed the sea got worse and the wind raged.
The idea was to resume sailing immediately after the front, in order to arrive where the Pacific and Atlantic Oceans meet with improving conditions.
The worst would then be behind us with ample time to go up to the Atlantic before any new depression could endanger us.
I.e. go north of Tierra del Fuego before a new depression hit.


Pacific and Atlantic Oceans meet at Cape Horn - photo © Global Solo Challenge

Pacific and Atlantic Oceans let us pass

The choice was spot on, at the first signs of the passage of the front we prepared to manoeuvre.
As the wind turned from southwest to northwest, we headed back on course towards Cape Horn.
Initially the majestic sea was still terrifying, the boat flew in pure uncontrollable surfs with just two tiny sails.
The cloud cover was torn, the sun through the clouds on our faces, the sea was slowly realigning itself on the new direction of the wind.
The cross sea was fading.
Shortly after we passed the islands of Ramirez and although the sea was confused and some breakers hit us we did not fear for the safety of the boat.

Soon we found ourselves shaking of the one reef, at first just one going from 4 reefed main to 3 reef, then we dropped the storm jib and hoisted the staysail.
Everything was looking good, with the seabed rapidly rising it crucial that conditions were improving and calming down.
It was now not long before we crossed the imaginary line where Pacific and Atlantic oceans meet.
We decided to stay way off Cape Horn in deeper waters with less probability of dangerous sea.
However, the wind and the sea decreased rapidly and we ended up rounding the cape without even seeing it, under the typical sky of a recently passed cold front.

A few hours later we even hoisted the spinnaker and in the protected waters after the cape we decided to go for the Strait of Le Maire.
We had no idea what the currents were doing in those places, we only had a photocopied page of a pilot book.
"The Strait of Le Maire is to be avoided at all costs in adverse wind and current conditions".
We had no idea what the current was going to do, we didn't have the Ushuaia tide tables.
We thought then about going outside the Isla del Los Estatos.

One last unforgettable ride


We arrived at the mouth of the Strait of Le Maire in light winds.
Behind us we looked towards where the Pacific and Atlantic Oceans meet, we had passed.
We were sheltered from the snow-capped mountains (in the height of summer) of Tierra del Fuego.
Slowly we noticed that we were accelerating towards the strait, we had arrived right at the change of flow of the current.
When we entered the strait the wind was almost gone but the current added three knots to our speed.
We were a bit apprehensive not knowing anything about that place and with nautical charts that didn't seem to have been updated anytime recently.
We saw worryingly shallow water on our depth sounder but by now we would not have had the sailing speed even to turn around and go back.

The sea span in vortexes, there were eddies everywhere around us, brown waters that clearly raised from the bottom of the shallow seabed.
Contrasting flows created areas with bubbling water and waves rising out of nowhere.
We had only about three or four meters of water under the keel with no idea if there were rocks or other dangers.
We only knew that the passage was navigable.
It looked damn scary and we certainly took stock of the advice in the pilot book, I could not imagine that place in a strong wind against tide situation.
The strait soon became a river rushing at speed, we were petrified gritting our teeth and couldn't do anything but let us be carried forward by the current.
The day was drawing to an end and wanted was to get out of that terrifying place.
Gradually the strait widened, the fury of the current lessened and pushed us north into a calm sea such as we have not seen in a very long time.

Pacific and Atlantic Oceans greet us

The sun gave us a sunset of infinite calm and peace.
We had been where the Pacific and Atlantic Oceans meet, we had rounded Cape Horn and we were finally out of danger.
The rest, as they say, is history, even if the rest of the leg was still long and tiring.
I will never forget Pacific and Atlantic Ocean, I will never forget Cape Horn, I will never forget the albatrosses.
I will never forget having lived to see my dream come true, a thought I will cherish that will always be mine, whatever happens to me.

Wednesday, June 9, 2021

The Mantis shrimp inspires a new material—made by bacteria

Photograph: Getty Images
 
From Wired 
 
By 3D-printing scaffolds and dipping them in microbe juice, scientists make robust structures that could one day lead to self-growing roads.

To humans, the mantis shrimp is known as the “thumb splitter,” due to its propensity to punch the digits of unfortunate fishers.
To its prey on the seafloor, the mantis shrimp is known as “death incarnate”—the crustacean cocks back its two hammer-like appendages under its face, releasing them with such force that they obliterate clam shells, one of the toughest materials in nature.
The mantis shrimp has even more fun with crabs, strategically blowing off their claws first so the prey can’t defend itself.
All that bashing puts serious stress on the hammers themselves.
So to deal with the constant punching, evolution gave the material of these weapons a “Bouligand” shape.
Instead of the layers of material neatly stacking one on top of another, the layers are twisted, almost like the helical structure of DNA.
So when a mantis shrimp’s hammer smashes into a thumb or a clam or a crab’s face, any crack in its structure will propagate in a twist pattern, dissipating the energy throughout the material.
As a result, the hammer doesn’t snap in half.
 
Neat, said engineers at the University of Southern California and the University of California, Irvine, who’ve invented a clever kind of material based on the mantis shrimp’s clobber-sticks.
(If you’re one for formal terminology, they’re called dactyls.) It’s a twist within a twist: They’ve been able to get minerals to grow within a 3D-printed shrimp-inspired Bouligand structure with the help of bacteria, of all things.
 
Courtesy of Qiming Wang
The researchers began by 3D-printing a simple lattice structure, basically a grid, out of a polymer.
As you can see in the image above, the resulting scaffold had plenty of empty space within—think of it as being like the beams that support a building.
They then dipped the whole structure in a bacterial solution and let it sit for 12 to 24 hours.
The Sporosarcina pasteurii bacteria in the solution attached to the polymer lattice and started secreting an enzyme called urease.

Courtesy of Qiming Wang

When the researchers dipped the structure into a second bath of urea and calcium ions, the urease kicked off a chemical reaction that created calcium carbonate.
This is the same material that gives a clam’s shell—as well as your own bones and teeth—their strength.
It’s also a component of the mantis shrimp’s hammer.
In the lab, as the researchers left the scaffolding in the solution, the calcium carbonate kept on accumulating, filling in the lattice entirely within 10 days, and giving the researchers a super-tough material made of a polymer skeleton and mineral innards.
You can see the structure’s progress in the image above.

Courtesy of Qiming Wang
The researchers were able to 3Dprint lattices with a variety of interior shapes, from wave patterns to crosses, as shown in the images above.
Row C shows where the mineral filled in gaps in the polymer skeleton.
In the colorful images of row D, you can see that calcium carbonate mineral deposits score high in stiffness (indicated in red), while the lattice ranks lower (shown in blue and green).
But what the researchers were really after was the Bouligand structure, which gives the mantis shrimp’s hammer its resilience.
In the image below, there are four different types of lattices.
Image A shows what those 3D-printed structures look like, with Type I being just a linear stack of material, while Type IV is the Bouligand structure—each layer shifts 45 degrees, creating a kind of swirl.
In row C, the images show the dark bands of polymer filled in with white calcium carbonate.
Type I is arranged like aisles in the grocery store, whereas Type IV looks more chaotic.
 
Courtesy of Qiming Wang
 
A good kind of chaotic, as it happens.
When the researchers tested the strength of each lattice, the Type IV Bouligand structure absorbed 20 times as much energy as Type I.
“This kind of microstructure makes sure that this kind of composite is very tough,” says University of Southern California engineer Qiming Wang, coauthor on a new paper describing the findings in the journal Advanced Materials.
“When you have a crack, that crack will propagate in the twist pattern to dissipate the energy inside the material.” In fact, the material absorbs more energy than natural nacre (mother of pearl), which gives some shells their strength, and also beats existing artificial materials, Wang and his colleagues say.
 
Just as the mantis shrimp’s hammer absorbs the energy of its punches without snapping, so too might materials developed with this new method.
For potential uses, Wang says to think of body armor, which needs to dissipate a bullet’s energy.
Calcium carbonate is also fairly lightweight, so scientists might also be able to grow tougher panels for aircraft or even skins for robots, Wang says.
 
“This is, for me, a way to do manufacturing in the future, and I'm not the only one saying that,” says Purdue University civil engineer Pablo Zavattieri, who wasn’t involved in this research.
In traditional manufacturing, defects can sneak in.
Nature, on the other hand, has, over the course of millions of years, developed the wondrous Bouligand structure in the mantis shrimp’s hammer, and it’s a pattern that can be replicated with a simple lattice and a bacterial bath.
“Nature is, in that way, impeccable,” Zavattieri says.
“Nature is a 3D printer.”
 
Another thing that makes this bacteria-built material special is its ability to regenerate.
Like, what if instead of building roads, we grew them? “If we have damage, you just introduce bacteria inside, and it can grow it back,” says Wang.
“These structures are very tough, very strong, and can potentially repair themselves.”
 
The researchers aren’t there quite yet—they got the bacteria to grow minerals in controlled conditions in the lab, and even then it was only in small quantities.
Scaling up for constructing roads would bring additional engineering challenges; for instance, getting the right ratio of supporting scaffold to hardening material.
But Zavattieri is actually already working on 3D-printing concrete.
“I don't think it's super crazy,” he says.
“We can totally have robots print the classic scaffold, leave the bacteria there, and then let them grow the material for 10 days.”
So perhaps one day the unabashed bashing of the mantis shrimp could help fix America’s busted infrastructure, instead of just breaking thumb.
 
Links :

Tuesday, June 8, 2021

How high-tech robotic surfboards could change our understanding of the Gulf Stream

From WashingtonPost by Matthew Capucci

How high-tech robotic surfboards could change our understanding of the Gulf Stream
The ‘saildrones’ can go places that most science ships can’t

The Gulf Stream, the warm water current that weaves a serpentine path from the west Atlantic to the United Kingdom, routinely brews some of the most extreme winter storms in the northern hemisphere, disrupting shipping and marine commerce while affecting weather throughout the globe.

The Gulf Stream is also an enormous absorber of carbon dioxide, trapping greenhouse gases and preventing the pace of climate change from accelerating further.

Scientists are now hoping to gain a better understanding of what makes the Gulf Stream tick by launching “saildrones” — or surfboard-like “uncrewed surface vehicles” — that will ride the waters and transmit observations for up to a year.
Developed by the Saildrone company in Alameda, Calif., they are used to survey weather and ocean observations and can cover thousands of square miles with no carbon footprint.

“We had a competition where we asked what people would do if they had a Saildrone for a month,” said Anne Miglarese, Saildrone’s program executive officer for impact science.
Jaime Palter, a professor of oceanography at the University of Rhode Island, said she would “stick it in the Gulf Stream,” Miglarese recalled.

Saildrone was enthusiastic about the proposal.
It loaned Palter a unit that was launched from Newport, R.I., on Jan. 30, 2019.
Palter’s aim was to better understand how currents like the Gulf Stream fit into the global carbon cycle and how much of a net carbon sink, or absorber, they are.
Humans routinely emit more than 35 billion tons of carbon dioxide annually, about a third of which is believed to immediately end up in the oceans.


Recent Saildrone missions in the Antarctic have shown that the ocean’s role in the carbon cycle may not be as well understood as once believed, which could result in significant changes in how scientists model and research the dynamics of climate change.

“We circumnavigated the Antarctic last year on another philanthropic mission focused on monitoring carbon,” Miglarese explained.
“The scientific consensus [at the time] was that the Antarctic was a sink for carbon.
Our science showed it was a source part of the year.”

According to the paper published with the data, “observing the Southern Ocean is challenging due to its size, remoteness, and harsh conditions,” a problem that is also inveterate to the North Atlantic during winter.

The challenges of collecting data from the Gulf Stream motivated Saildrone to work with partners to explore the current’s role in the sequestration and release of CO2.
They’re partnering with NOAA, along with Palter, to analyze the findings once obtained.

“We need a more accurate global carbon budget, and missions like this one will support that and help test our assumptions,” Miglarese said.

A dramatic view of Hurricane Florence as seen from the International Space Station.
A tropical cyclone is a generic term for a rapidly rotating tropical storm with a low-pressure center and clouds spiraling toward the center of the system.
In the Atlantic, they are also called hurricanes; in the Pacific they’re called typhoons.

With the help of a roughly $1 million investment from Google, Saildrone will be launching a half dozen of its drones to roam the North Atlantic.
The company has three sizes of drones and is choosing its 23-foot Explorer model for this mission.

The drones resemble enormous surfboards with fins and have a 16-foot sail on top that is used as a mast for weather instruments, solar panels and a camera.
It can travel at speeds of three knots on missions lasting up to a year at a time.

The drones are powered by sunlight and wind and wirelessly transmit compressed data back to shore.
Some Saildrones are equipped to monitor populations of sharks and other fish and algae.

The design builds upon the last iteration of the Saildrone Explorer, which was used in Palter’s 2019 study.
During that mission, a strong gust of wind tore the wing from the Saildrone — but that didn’t halt the project.

Saildrone Hurricane Wing Testing

“The wing ripped in half, but the drone continued to operate for about 10 days,” said Miglarese.
“They got more data than they’ve ever gotten before.
After that mission, Richard, [Saildrone’s CEO], redesigned the wing.
Now they are meant specifically for this work.”

The new “hurricane wings” will be added to Saildrones that the National Oceanic and Atmospheric Administration will place in the tropics during hurricane season as part of a later project.

Saildrone’s latest endeavor will investigate more than just dissolved carbon concentration.
The drones will collect weather and water temperature data in a part of the Atlantic largely bereft of weather buoys.
That could prove enormously beneficial in improving the accuracy of weather forecasts.

NOAA’s Climate Prediction Center is predicting a 60% chance that the 2021 Atlantic hurricane season will be above-normal, with 13–20 named storms.
About half of those are expected to become hurricanes, and 3–5 of those are expected to become major hurricanes, Category 3 or higher. 

The European Centre for Medium-range Weather Forecasts, or ECMWF, hosts the most powerful weather model in the world and is often considered the most accurate.
It hopes that data provided by the Saildrones will improve forecasts made for Europe.

“We will ingest some of the data from the Saildrones, but not all,” Philip Browne, a data scientist at the ECMWF, wrote in an email.
“In particular we will use the surface pressure data operationally, and that will go straight into the weather forecasts we produce.”

That could bring model improvements as soon as the data starts flowing.

Ocean current data from the Gulf Stream will be vetted and used only internally at first because scientists at the ECMWF need to make sure the data is processed and handled by computers correctly.

“The many other sensors and observation types carried by the Saildrones have different routes into the system,” Browne said.
“For example, the sea surface temperature measurements will end up in our forecasts.”

He explained that sea surface data is first taken in by the United Kingdom Met Office, which produces a global sea surface temperature analysis, which is fed into the ECMWF model.
“The data should be available for all weather centres to use if they can,” Browne wrote.

In the meantime, Miglarese said she is excited for what’s ahead for Saildrone and is looking to the rollout of its biggest model yet — the Saildrone Surveyor.
“We just launched a 72-foot drone that does bathymetric measurements,” she said.
Bathymetry describes the shape, depth and topographic features of the sea floor.
“It’s a big vessel. It’s pushing a lot of power.”

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Monday, June 7, 2021

In sailing, women are taking more than a seat


The all-female Team SCA, of which the British sailor Sam Davies was the skipper, during the Cape Town Practice Race of the Volvo Ocean Race 2014-15.
Credit... Ainhoa Sanchez/Volvo Ocean Race, via Getty Images

From NYTimes by David Schmidt

They have waited years to earn respect, but now they are winning races and skippering and owning boats.

Competitive sailing has long been an old-boys’ club, yet over the past several decades, women have not only been joining the sport, they have also sometimes been taking charge of it.
They have become senior executives of sailing organizations and yacht clubs, and skippers and owners of boats.

For the first time, in 2018, a female skipper won an around-the-world race, one of the most grueling events in any sport, and five all-women’s teams have completed the round-the-world Volvo Ocean Race (now called just the Ocean Race).
The last American sailor to win an Olympic gold medal was a woman, in 2008, and women have also hoisted the America’s Cup.

Dawn Riley did that in 1992, and she now leads one of the pre-eminent high-performance sailing training centers in the United States.
Cory Sertl is president of US Sailing, the national governing body, and vice president of World Sailing, the international governing body.
And Lindsey Duda Coe was one of the winners of the Chicago Yacht Club’s 2019 Race to Mackinac on the boat she owns.

“Women athletes have been participating in Olympic sailing since 1988,” Sertl said.
“So, there are now more women who have experienced sailing at the highest level, and a number of these women have been drawn into being officials and leaders in the sport.”


Anna Tunnicliffe Tobias of the United States, competing at the 2008 Olympic Games in Beijing, where she won a gold medal.Credit...
Clive Mason/Getty Images

Pamela Healy, a bronze medalist at the 1992 Summer Olympics, said having female leaders was vital.

“There was a Harvard Business Review study on boardroom dynamics that showed that corporations are more successful when they have at least three women voting members on their board of directors,” she said.
“Women add a diverse perspective that is invaluable to decision making and problem solving.”

In addition to winning countless races, Healy has served on the boards of directors of the St.
Francis Yacht Club and the San Francisco Yacht Club and is the president of the St.
Francis Sailing Foundation.
“I feel respected,” she said.
“I don’t feel that I’m a token.”

Still, she sees opportunities for improvement.
“It’s important to see photos of women in blazers on the wall, so women feel represented,” Healy said, referring to yacht-club leadership.
“And we need to improve boat ownership. That will equate to true equality.”

Some gender accomplishments have been hard-won.
Riley said she once discovered that a male crew member with similar duties and experience was being paid twice as much as she was.

“I’m pretty happy with where I’ve gotten,” said Riley, who later served as team captain of the mostly female America’s Cup team­ Mighty Mary.
“But my path was decidedly different than if I was male.”

Sertl, who was a member of the 1988 United States Olympic Sailing Team, said sailing was still evolving.

“I feel really fortunate in the U.S. to have tremendous support from men and women,” she said of her position at US Sailing.
“But World Sailing is different and changing.”

For example, five years ago, Sertl made a motion at a meeting of World Sailing to have gender equity in classes of boats and in the number of medals and athletes at future Olympics.
At that time, there were more sailing events for men than for women.
“Three men in the room objected,” she said.

While women have competed for sailing medals since the 1988 Summer Olympics, and the International Olympic Committee is mandating a push for gender equality, Sertl wants to see more female coaches who can serve as role models for aspiring female Olympic athletes.
“Many female athletes coming up haven’t had a high-performance female sailing coach,” she said

Sam Davies is one of the most accomplished offshore sailors in the world, male or female, and has competed three times in the Vendée Globe, the solo around-the-world race.
Far more people have reached the summit of Mount Everest than have completed the Vendée Globe, which takes about 80 days to finish.

“I think that some of the hardest challenges I face are not because I’m a woman skipper, but because what I do is hard,” said Davies, who has also skippered the all-women’s Team SCA in the 2014-15 fully crewed Volvo Ocean Race.

But she also said that women had a possible advantage in her sport: sponsorships.

“It’s maybe easier if you’re a good woman skipper,” she said of the Vendée Globe.
“Women can bring a good return on investment for a sponsor, because we’re a minority in a male-dominated sport.”

But finding sponsorship and acquiring the right boat are different matters.
Of the 30 boats that were on the starting line of the 2020-21 Vendée Globe, five were skippered by women.
Eight were new designs, all skippered by men.
“What’s missing is a sponsor who will give a boat that’s capable of winning to a female skipper,” Davies said.


The skipper Wendy Tuck, winner of the 2017-18 Clipper Round the World Race.Credit...Miguel Rojo/Agence France-Presse — Getty Images

So far, Wendy Tuck is the only female skipper to have won an around-the-world race.

“When I started skippering, I didn’t realize there wasn’t one,” said Tuck, who won the 2017-18 Clipper Round the World Race.
Unlike the professional crews of the Ocean Race, Clipper crew members pay to race aboard identical boats under the tutelage of experienced skippers like Tuck.
While this may lower the race’s level of competition, it increases the skipper’s leadership challenges.
“My crews varied, but they were roughly 30 to 40 percent women,” Tuck said.
“I’ve been on non-Clipper trips where the men say that they like having females aboard, because it changes the dynamics.”

Although the number of women who are skippers has been growing, they are still outnumbered by men, which can hurt confidence.

“A lot of women still believe that men are more capable than women,” said Kristina Plattner, who is skipper of the TP52 Phoenix 12, which she races on the 52 Super Series circuit.
“But it’s not true, especially for helming a yacht.”

Which is why role models are critical.
“I really hope that other girls can see women out there driving,” said Duda Coe, owner of the Santa Cruz 52 Sin Duda.
She admitted that being a female skipper was sometimes a struggle.
“Even on a boat I own, I’ve been intimidated by guys,” she said.

The gender disparity, she added, is part cultural and part physiological.
“Body size and strength are important,” Duda Coe said, but they are not the whole picture.


Anna Tunnicliffe Tobias after her gold medal victory in the Laser Radial class event in Beijing.
Credit... Clive Mason/Getty Images

Anna Tunnicliffe Tobias, who won the last United States sailing Olympic gold medal, said the importance of those factors depended on the task.

“I’m fairly fit, I think, but I cannot put out the wattage on the winches that some of the guys put out for 10 to 20 minutes, just because I don’t have the weight or height to put behind it,” she said.
“However, there are many other positions that I can do in the back of the boat, like drive, call tactics and navigate.”

Still, Tunnicliffe Tobias, who is also an elite-level CrossFit athlete, acknowledged that Grand Prix sailing is highly competitive.
“At the elite level, there are only so many spots available,” she said.
“I was once told, ‘If you want a spot on the boat, earn it’. It resonated well with me.”

More women are getting the opportunity to earn their spots aboard the most sophisticated boats because of efforts like SailGP’s mandate that teams have at least one female sailor.
Other Grand Prix events, such as the Ocean Race, offer incentives, like having a larger crew, to teams that race with female sailors.

So while women have made great strides in sailing, Riley isn’t content.
“When you shatter the glass ceiling, it’s not the first woman, it’s the third,” she said.
“That’s when you start to get equity.”

Sunday, June 6, 2021

Maritime infographic: The fall of the mighty Titanic

The above infographic represents the best estimations science and history can currently make as to what happened in the moments immediately before and after the Titanic disappeared beneath the surface.
 
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