Sunday, February 28, 2021

The Long Leg , Edward Hopper (1935)

Messing about on boats all summer is a holiday lived in the present; that’s the sense of this picture.
The boat remains still; it is the wind and water that move it along.
Hopper’s coolly beautiful painting of a sailboat off the New England shore perfectly expresses this curious fact about sailing.
And in conditions like these – a hot blue day, windless, the sun beating down on the blanched sand – the boat is lying almost motionless to one side, solitary as the characteristic Hopper lighthouse in the background.
Like the water itself, the painting is almost entirely composed in shades of blue.
 
Links :

Saturday, February 27, 2021

Underwater photographer of the year 2021

Renee Capolzzola (USA), for her graceful image: “Shark’s Skylight“.
 
The full set of UPY2021 results is now available to view in the Winners’ gallery, and the complete collection is available to download and keep in the free Yearbook.
The UPY team would like to thank all the talented photographers who supported this year’s competition with their pictures, especially in these challenging times.
We hope that this year’s stunning collection of winning images provides a welcome escape to everyone who enjoys them and a chance to reconnect with the underwater world.

Friday, February 26, 2021

The Titanic disaster and its aftermath

View of the bow of the RMS Titanic photographed in June 2004 by the ROV Hercules during an expedition returning to the shipwreck of the Titanic.
(Courtesy of NOAA/Institute for Exploration/University of Rhode Island)


From Hydro by Albert E. Theberge

Understanding the Unthinkable

In the night of 14 April 1912, the unthinkable happened.
The mightiest ship afloat, the brand new White Star Line ship Titanic, was on its maiden voyage from Southampton, England, to New York.
The ship was advertised as unsinkable.
And, if unsinkable, why should there be adequate lifeboats for all of the passengers and crew? The ship departed from Southampton on 10 April.
Less than five days later, it was at the bottom of the Atlantic Ocean.
More than 1,500 people perished within three hours of striking an iceberg, which ripped the bottom out of the ship.

How this happened is a story told many times.
Human hubris, unswerving trust in the infallibility of technology, and the commercial impetus of fast Atlantic passages all contributed to the loss of the ship and the accompanying loss of life.
Even as the ship was settling in the waters of an icy North Atlantic, some survivors reported that there was a belief among many passengers that the ship was the safer place to be; accordingly, not all the lifeboats were filled to capacity.

This accident shocked the international community.
The British and American governments investigated the accident – the British determined: “That the loss of said ship was due to collision with an iceberg, brought about by the excessive speed at which the ship was being navigated.” Certainly, that was the major factor.
However, like many accidents, there were a number of contributing causes.
These included: watertight bulkheads that were improperly designed; an insufficient number of lifeboats and life rafts; apparent lack of concern by the captain concerning reports of ice prior to collision with the iceberg; little training of crew in emergency procedures including lowering of lifeboats; no radio watches on nearby ships which could have assisted in lifesaving efforts; and, remarkably, not even binoculars for the ship’s lookouts.

Steamship Titanic showing length as compared with highest buildings.

Both the British and American governments arrived at similar conclusions and recommendations following the loss of the Titanic.
The chief recommendation was that all ships be equipped with sufficient lifeboats for passengers and crew, that all ocean-going ships maintain 24-hour radio-telegraph watches, and that bulkheads be designed such that flooding of any two adjacent compartments would not result in sinking of a vessel.
These recommendations and others were adopted by the first International Convention for the Safety of Life at Sea (SOLAS) at a conference held in London in 1914.

Development of Seafloor Mapping Technologies


Commercial concerns saw an opportunity in the Titanic disaster and began searching for a means to determine the presence of icebergs and other unseen or submerged obstructions forward of moving vessels.
European and North American inventors joined the race.
In 1912, Reginald Fessenden, a Canadian inventor and radio pioneer, joined Submarine Signal Company, a forerunner of today’s Raytheon, and began work on an electro-acoustic oscillator similar to a modern transducer.
This oscillator was originally designed for both ship-to-ship communication and to receive reflected sound from an underwater object.
In late April 1914, Fessenden tested this device off the Grand Banks on the US Revenue Cutter Miami and succeeded in reflecting sound off an iceberg at a range of approximately two miles and hearing the return echo.
A second echo was heard that was determined to be from the bottom.

Submarine warfare during World War I accelerated research into the field of acoustics.
By the end of the war, the use of acoustics for both detection of objects in the water and measuring depth had been proven.
In 1922, the USS Stewart, equipped with a Hayes Sonic Depth Finder that utilized a Fessenden oscillator, ran a line of soundings across the Atlantic Ocean taking over 900 individual soundings.
The profile obtained from these soundings was published in the first issue of the International Hydrographic Review.
Piano-wire sounding systems became obsolete overnight.
Although leadline sounding continued for a number of years in shallow water, acoustic sounding systems replaced the leadline for most purposes within two decades.

World War II further accelerated the development of directional sonar systems (called Asdic in England).
Although meant originally for detection of submarines, these systems ultimately developed into modern side-scan sonar systems.
Underwater photography equipment and magnetic anomaly detection (MAD) instruments were in their infancy during this period.
MAD systems were proved effective in detecting submarines.
An early use by hydrographers of the complementary use of sonar, underwater photography and MAD gear was in the charting of ships torpedoed off the United States East Coast.
This was done by Coast and Geodetic Survey (C&GS) officers working off the Coast Guard buoy tender Gentian in 1944.

Following the war, there were further advances, including the development of an early side-scan sonar system called Shadowgraph in 1954 by German scientist Julius Hagemann, who was working at the United States Navy Mine Defense Laboratory.
This system remained classified for many years, but civil use of side-scan began developing shortly after this advance.
In the commercial sector, Harold Edgerton of the Massachusetts Institute of Technology (MIT) and Martin Klein, also of MIT, were early pioneers.
Edgerton turned a bottom-penetration sonar on its side in 1963 and imaged a sunken lightship from a C&GS vessel.
Edgerton was a founder of EG&G and discovered the Civil War era USS Monitor off Cape Hatteras with an EG&G commercial side-scan system.
Martin Klein began his career with EG&G but left to found Klein Associates, a name synonymous with side-scan technology.

Advances in depth measurement technology paralleled the development of side-scan technology.
In April 1961, engineers at General Instruments Corporation developed a proposal for BOMAS, Bottom Mapping Sonar.
Quoting from the proposal: “BOMAS derives bottom profile information from the intersection of the ocean bottom with a vertical plane perpendicular to the heading of a ship.
The sonar data is processed automatically and in real time to provide a depth contour strip map….
A sonar intensity map can be provided simultaneously….” 
Multi-beam sounding with its attendant bottom reflectivity mapping capability was born.
Two years later, the first prototype multi-beam system was installed on the USS Compass Island and subsequent units installed on Navy survey ships.
In the meantime, the acronym had changed to SASS (Sonar Array Sounding System).
By the late 1970s, the technology had migrated to the civil community and has since displaced single beam sounding systems as the standard seafloor mapping tool.

Painting of the Titanic sinking by the bow, with people rowing a lifeboat in the foreground and other people in the water.
Icebergs are visible in the background.
(Engraving by Willy Stöwer: Der Untergang der Titanic) 

Finding Titanic and the Aftermath of the Discovery


In the immediate aftermath of the sinking, proposals to locate the sunken Titanic were discussed and ultimately dismissed because the wreck lay well beyond the limits of technology at that time.
Through the decades, the development of subsea technology finally provided the means to locate the wreck and subsequently to not only investigate it using remote technology, but also to dive to the wreck and conduct a series of investigations that included surveys of the interior of the ship.

In July 1985, the final search began, with Ifremer deploying their newly developed side-scan sonar SAR vehicle on a mission led by Jean-Louis Michel on the research vessel Le Suroit.
That survey covered 70% of a 150 square nautical mile survey box without locating the Titanic.
Picking up the search in August, the WHOI team, led by Robert Ballard aboard the research vessel Knorr, utilized the towed vehicle Argo, with a 100kHz side-scan sonar, and three low-light black and white video cameras.
Ballard’s team relied on the optical system to locate the Titanic, and in the early morning hours of 1 September, the unmistakable form of a boiler made it clear that the search was over.
Titanic’s final resting place had been found.

Since the discovery in 1985, a series of expeditions have visited the Titanic with a variety of goals.
Ballard and Woods Hole returned to the wreck in July 1986 on the WHOI research vessel Atlantis II, with the submersible Alvin, and the ROV Jason Jr.
The 1986 expedition photographed and filmed the wreck, focusing on the largely intact bow section.
Working from the data collected from the 1985 Argo survey as well as 1986 data, WHOI’s William Lange and others assembled a preliminary site map of the Titanic wreck site that delineated the site from the bow to the stern section and plotted a wide range of features scattered on the seabed.
A private venture funded and led by RMS Titanic, Inc., the salvor-in-possession of the wreck (RMST), and technically supported by Ifremer, returned to the wreck in July 1987 and made 32 dives to recover some 1,800 artifacts from the seabed, the first of a series of recovery dives made by RMST until 2004, which ultimately salvaged nearly 5,000 artifacts.

The remotely operated vehicle (ROV) Hercules exploring the bow of the Titanic, 2004.
(Courtesy: Institute for Exploration/University of Rhode Island/NOAA


Dives made by documentary film crews and James Cameron (whose first dives were in 1995) working with the P.P.
Shirsov Institute, captured dramatic images of the wreck as well as additional technical information and a more detailed view of aspects of the wreck site in the Mir submersibles.
In particular, Cameron’s extensive documentation and penetration of the interior of the bow with small ROVs known as ‘bots’ provided incredible insights into the ongoing processes of environmental change and preservation inside the ship, as well as evidence of what had occurred during the sinking of the Titanic.
Cameron’s work has arguably done more to share the Titanic as a wreck site with a greater audience than anyone else.

The scientific products of the various expeditions include a detailed analysis of the microbiological corrosion of the ship’s steel (led by Roy Cullimore), geological studies of the sediments and current studies (by the Shirsov Institute), a detailed sonar survey of the bow where the Titanic struck the iceberg, photo mosaics of the bow section, and forensic studies of the ship’s sinking sequence and break-up.
In addition, RMS Titanic, Inc. commissioned the creation of an ‘archaeological GIS’ map delineating where the 5,000 artifacts had been recovered from between 1987 and 2004.
That GIS, which is being completed by RMST under contract by the Center for Maritime & Underwater Resource Management of Michigan, a private non-profit, is reported to be nearly complete.

The National Oceanic & Atmospheric Administration’s Office of Ocean Exploration conducted two missions to the Titanic in 2003 and 2004.
As the nation’s ocean agency, NOAA has an interest in the scientific and cultural aspects of the Titanic.
NOAA’s focus is to build a baseline of scientific information from which we can measure the processes and deterioration of the Titanic, and apply that knowledge to many other deepwater shipwrecks and submerged cultural resources.
The 2003 mission, with the Shirsov Institute, had several key goals, the first being to catalogue any anthropogenic activities currently impacting the wreck site, or evidence of such activity since its discovery in 1985.
Digital imagery was obtained and a deck-view mosaic of the bow section was created.
Additionally, ongoing bacteriological analysis was conducted as well as basic oceanographic research.

The 2004 Mission, Conducted On Board the NOAA Research Vessel

Ronald H. Brown, working with Robert Ballard, then (and now) with the University of Rhode Island and the Institute of Archaeological Oceanography, utilized an ROV to continue the assessment of the wreck’s ongoing environmental changes and the bacteriological work of Roy Cullimore.
One other key achievement of the 2004 mission was the completion of a topographic map of Titanic Canyon and the surrounding area, including the wreck of the Titanic, with a Seabeam 2112 multi-beam sonar system.
The digital terrain model of this large area of seabed places the Titanic within a larger geological and geographical context.

NOAA also participated, as did Woods Hole, the National Park Service, the Institute of Nautical Archaeology, the Waitt Institute and contracted partners such as Phoenix International, Ltd., in RMS Titanic, Inc.’s last (to date) expedition to the wreck in August 2010.
This mission, with a non-recovery scientific focus, focused on William Lange’s and the WHOI Advanced Imaging and Visualization Laboratory’s work to create a detailed 2D and 3D visual mosaic of the site.
To do so, it made a detailed survey using the Waitt Institute’s REMUS 6000 autonomous underwater vehicles of an approximately ten square nautical mile survey zone around the wreck site, with a series of closer, higher resolution surveys of the area delineated in the 1986 WHOI map of the site and even closer surveys of key features and areas of the site.
That project was successful in generating the mapping data as well as comprehensive visual coverage of the wreck, including detailed photo mosaics of a number of features in the artifact scatter, which included sections of the ship’s hull, machinery and equipment and other artifacts.

This composite image, released by RMS Titanic Inc., and made from sonar and more than 100,000 photos taken in 2010 by unmanned, underwater robots, shows a small portion of a comprehensive map of the 3-by-5-mile debris field surrounding the bow of the Titanic on the bottom of the North Atlantic Ocean (Courtesy: AP Photo/RMS Titanic Inc.)

What is clear in this brief overview is that the last few decades have witnessed a revolutionary expansion of humanity’s capacity to not only locate deep-sea shipwrecks, but increasingly to capture imagery and data that essentially ‘virtually raises’ these wrecks for ongoing research as well as public education.
In many ways, the Titanic and the surrounding area are likely to be the best-studied section of the deep ocean floor.
That status has come because of the iconic nature of the wreck and the potential for profit from the opportunity to connect to this ship and its tragic loss either through a tour of the recovered artifacts or a virtual tour on film or in a photograph.
At the same time, measurable and important science has been conducted, and in that, a way forward for not only this site but others has been demonstrated, especially in the adaptation and adoption of technology to access and learn from sites once thought unreachable.

Links :

Thursday, February 25, 2021

Scientists use nuclear reactor to investigate Amelia Earhart’s mysterious disappearance

Earhart beneath the nose of her Lockheed Model 10-E Electra, March 1937, Oakland, California, before departing on her final round-the-world attempt prior to her disappearance.
Credit: Wikimedia Commons.

From ZMEScience by Tibi Puiu

A metal plate thought to have once belonged to Earhart's plane was probed for hidden secrets using neutron beams.

One of the bravest women of the 20th century, Amelia Earhart, vanished unexpectedly during her attempt to fly around the world.
Now, scientists have turned to nuclear technology to analyze a piece of metal debris that some suspect was part of Earhart’s wrecked plane. In doing so, they hope to piece together the final moments of the pioneering aviator’s final living hours. 

A tragic end to a brave pioneer

Amelia Earhart was the first female pilot to fly across the Atlantic Ocean.
In 1937, Earhart and her navigator, Fred Noonan, were flying their Lockheed Model 10-E Electra on an even more ambitious quest: flying around the world.
On July 2, 1937, they were about six weeks and 20,000 miles into their journey when their plane suddenly crashed en route to Howland Island in the Pacific, which is halfway between Hawaii and Australia. 
 

Howland island with the GeoGraage platform (NGA/NOAA source)
 
The Howland Island is a flat sliver of land about 2,000 meters (6,500 feet) long and 460 meters (1600 feet wide), so it must have been very difficult to distinguish from similar-looking clouds’ shapes from Earhart’s altitude.
Of course, Earhart and Noonan were well aware of the challenges, which is why they had an elaborate plan that involved tracking their routes using celestial navigation and linking to a U.S. Coast Guard vessel stationed off Howland Island using radios.

But despite their well-thought-out contingency plans, the pair were simply flat out of luck.
When they took off, witnesses reported that a radio antenna may have been damaged by the maneuver. On that morning, there were also extensive overcast conditions.
Later investigations also showed that the fliers may have been using outdated, inaccurate maps.
 
 
On the morning of July 2, 1937, at 7:20 AM, Earhart reported her position to the crew at the Coast Guard vessel, placing her plane on a course at 32 kilometers (20 miles) southwest of the Nukumanu Islands.
“We must be on you, but we cannot see you. Fuel is running low. Been unable to reach you by radio. We are flying at 1,000 feet.”

The ship replied but there was no indication that the signal ever reached Earhart’s plane.
The Coast Guard ship released its oil burners in an attempt to signal the flyers, but they weren’t seen by all accounts.
Noonan’s chart of the island’s position was off by about five nautical miles, subsequent investigations showed, and it seems likely that the plane ran out of fuel.

Despite a huge search and rescue mission involving 66 aircraft and nine ships, the fate of the two flyers remains a mystery to this day.
With the years, the mystery only intensified, amplified by countless conspiracy theories surrounding Earhart’s last days.

Neutrons and dirty metal plates

While watching a National Geographic documentary on the disappearance of Earhart, Daniel Beck, a pilot who also manages the engineering program for the Penn State Radiation Science and Engineering Center (RSEC), home to the Breazeale Nuclear Reactor, was shocked by a particular scene discussing an aluminum panel believed to be part of the wrecked airplane.
The documentary ended with the idea that, perhaps, sometime in the future, technology will advance to the point where scientists can elucidate more information from the panel.
“I realized that technology exists. I work with it every day,” Beck said.

The scientist got ahold of Richard “Ric” Gillespie, who leads The International Group for Historic Aircraft Recovery (TIGHAR) and was featured in the documentary, and offered to analyze the metal part using neutron technology at his lab. 
 

Kenan Ünlü, director of the Penn State Radiation Science and Engineering Center, holds a metal patch that might be from Amelia Earhart’s airplane.
Credit: Kenan Ünlü/Penn State.

The metal panel had been recovered in storm debris on Nikumaroro, a Pacific island located about 480 kilometers (300 miles) away from Howland Island.
Some have suggested before that Earhart’s plane made an emergency landing on the reef surrounding the small, uninhabited island.
A human skeleton was even found in 1940, and although the bones were lost, a 2018 study found that the historical records of the bones’ measurements matched Earhart’s closer than 99% 0f the general population.

A skull fragment that may be from the original skeleton was found in a storage facility in a museum on a nearby island and is currently being tested to see if it is a genetic match for any of Earhart’s relatives. Beck’s goal was to perform a similar investigation, only instead of genetics, he wanted to use the reactor’s neutron beams to reveal the history of the metal patch.
Perhaps they could find a long-faded serial number or other marks that might link the debris to the Electra.

Beck and colleagues placed the sample in front of the neutron beam, while a digital imaging place was placed behind the sample.
As the neutron beam passed through the sample and then through the imaging plate, an image was recorded and digitally scanned.

“As the beam passes through, if it were uniform density, we wouldn’t see anything,” Beck said.
“If there’s paint or writing or a serial number, things that have been eroded so we can’t see with the naked eye, we can detect those.”

This investigation revealed that the metal plate had axe marks along the edges, except for one of the edges where the metal must have snapped from whatever it was attached to.
In other words, not much linking it back to Earhart.

“It doesn’t appear that this patch popped off on its own,” Beck said.
“If it was chopped with an axe, we should see peaks for iron or nickel left by the axe along that edge. Neutron activation analysis gives us that detail at a very fine resolution.”

For now, the researchers plan on performing more examinations using more comprehensive experiments, including adjusting the irradiation time and power level of the reactor.

Even if they eventually don’t find anything in connection to Earhart, this inquiry is still valuable.
For one, it disqualifies the object so other people don’t waste time in the future.
Secondly, it sets a precedent that may spur more research with neutron radiography.
“It’s possible we’ll learn something that actually disqualifies this artifact from being part of Earhart’s plane, but I prefer the knowing! It is so exciting to work with scientists who share our passion for getting to the truth, whatever it is,” Gillespie said in a statement.

Links :

Wednesday, February 24, 2021

Princeton astrophysicists re-imagine world map, designing a less distorted, ‘radically different’ way to see the world






From Princeton by Liz Fuller-Wright

How do you flatten a sphere?

For centuries, mapmakers have agonized over how to accurately display our round planet on anything other than a globe.

Now, a fundamental re-imagining of how maps can work has resulted in the most accurate flat map ever made, from a trio of map experts: J. Richard Gott, an emeritus professor of astrophysics at Princeton and creator of a logarithmic map of the universe once described as “arguably the most mind-bending map to date”; Robert Vanderbei, a professor of operations research and financial engineering who created the “Purple America” map of election results; and David Goldberg, a professor of physics at Drexel University.

Their new map is two-sided and round, like a phonograph record or vinyl LP.
Like many radical developments, it seems obvious in hindsight.
Why nothave a two-sided map that shows both sides of the globe? It breaks away from the limits of two dimensions without losing any of the logistical convenience — storage and manufacture — of a flat map.

“This is a map you can hold in your hand,” Gott said.

In 2007, Goldberg and Gott invented a system to score existing maps, quantifying the six types of distortions that flat maps can introduce: local shapes, areas, distances, flexion (bending), skewness (lopsidedness) and boundary cuts (continuity gaps).
The lower the score, the better: a globe would have a score of 0.0.

“One can’t make everything perfect,” said Gott, who is also a 1973 graduate alumnus of Princeton.
“A map that is good at one thing may not be good at depicting other things.”

The Mercator projection, popular on classroom walls and used as the basis for Google maps, is excellent at depicting local shapes, but it distorts surface areas so badly near the North and South Poles that polar regions are usually simply chopped off.

 

In the Mercator projection, the polar regions are completely distorted — Antarctica looks bigger than all other continents combined — and distances are misleading: Japan and Hawaii look very far apart.
Under the system designed by Goldberg and Gott to quantify map errors, where lower numbers represent less distortion, the Mercator projection receives a score of 8.296.
Map by Daniel R. Strebe via Wikimedia Commons


Using their metrics, the best previously known flat map projection was the Winkel Tripel, with a Goldberg-Gott score of 4.563.
But that still had the “boundary cut” problem of splitting the Pacific Ocean and creating the illusion of great distance between Asia and Hawaii.


The Winkel Tripel projection, chosen by the National Geographic for its world maps, represents the poles more accurately than the Mercator, but it still distorts Antarctica badly and creates the illusion that Japan is hugely to the east of California, instead of its nearest neighbor to the west.
Goldberg-Gott score: 4.563
Map by Daniel R. Strebe via Wikimedia Commons

Clearly, a completely new approach was needed.
Gott drew a comparison to Olympic high jumpers: In 1968, Dick Fosbury shocked sports fans by arching his back and jumping over the bar backwards.
He set a new record and won a gold medal, and high jumpers have jumped backwards ever since.

“We’re like Mr. Fosbury,” Gott said.
“We’re doing this to break a record, to make the flat map with the least error possible.
So, like him, we’re surprising folks.
We’re proposing a radically different kind of map, and we beat Winkel Tripel on each and every one of the six errors.”

The inspiration came from Gott’s work on polyhedra — solid figures with many faces.

Polyhedral maps are nothing new — in 1943, Buckminster Fuller broke the world into regular shapes, and provided instructions for how to fold it up and assemble it as a polyhedral globe — but while he could protect the shapes of continents, Fuller shredded the oceans and increased many distances, such as between Australia and Antarctica.


Buckminster Fuller popularized the “Dymaxion” polyhedral projection, based on an unfolded icosahedron.
Antarctica is “round, as it properly should be,” said Gott, but this projection “shatters” the oceans.
Goldberg-Gott score: greater than 15
Imagery courtesy NASA’s Earth Observatory, with modifications by Mapthematics LLC

In a recent paper, Gott began considering “envelope polyhedra,” with regular shapes glued together back-to-back, which led to the breakthrough idea for the double-sided map.

It can be displayed with the Eastern and Western Hemispheres on the two sides, or in Gott’s preferred orientation, the Northern and Southern Hemispheres, which conveniently allows the equator to run around the edge.
Either way, this is a map with no boundary cuts.
To measure distances from one side to the other, you can use string or measuring tape reaching from one side of the disk to the other, he suggested.

“If you’re an ant, you can crawl from one side of this ‘phonograph record’ to the other,” Gott said.
“We have continuity over the equator.
African and South America are draped over the edge, like a sheet over a clothesline, but they’re continuous.”

This double-sided map has smaller distance errors than any single-sided flat map — the previous record-holder being a 2007 map by Gott with Charles Mugnolo, a 2005 Princeton alumnus.
In fact, this map is remarkable in having an upper boundary on distance errors: It is impossible for distances to be off by more than ± 22.2%.
By comparison, in the Mercator and Winkel Tripel projections, as well as others, distance errors become enormous approaching the poles and essentially infinite from the left to the right margins (which are far apart on the map but directly adjacent on the globe).
In addition, areas at the edge are only 1.57 times larger than at the center.


Gott, Goldberg and Vanderbei’s revolutionary, double-sided disk map minimizes all six types of map distortions. 
They used an equidistant azimuthal projection: a compromise projection, like the Winkel Tripel, with small errors in both local shapes and areas, instead of optimizing one at the expense of the other. 
Antarctica and Australia are more accurately represented than in most other maps, and distances across oceans or across poles are both accurate and easy to measure, unlike one-sided flat maps. 
Goldberg-Gott error score: 0.881Map by J. Richard Gott, Robert Vanderbei and David Goldberg

The map can be printed front-and-back on a single magazine page, ready for the reader to cut out.
The three cartographers imagine printing their maps on cardboard or plastic and then stacking them like records, to be stored together in a box or slipped inside the covers of textbooks.

“A thin box could hold flat, double-sided maps of all the major planets and moons in the solar system,” Gott said, “or a stack of Earth maps giving physical data, political boundaries, population density, climate, languages, explorers’ voyages, empires at different historical periods or continents at different geological epochs.”

To the best of their knowledge, no one has ever made double-sided maps for accuracy like this before.
A 1993 compendium of nearly 200 map projections dating back 2,000 years did not include any, nor did they find any similar patents.

“Our map is actually more like the globe than other flat maps,” Gott said.
“To see all of the globe, you have to rotate it; to see all of our new map, you simply have to flip it over.”

Flat maps that improve on the Winkel Tripel,” by J. Richard Gott III, David M. Goldberg and Robert J.
Vanderbei, was published on Arxiv on Feb. 15.
You can see their double-disk maps of Earth, Mars, Jupiter, the sun, and other heavenly bodies here.

Links :

Tuesday, February 23, 2021

Arctic shipper shows off a historical icebreaking voyage

Watch two super-powerful vessels break their way through the Northern Sea Route in mid-winter.
 
From BarentsObserver by Atle Staalesen

It is the first time that a commercial vessel sails across the Northern Sea Route in February.
The voyage of the Christophe de Margerie from Jiangsu in China to the remote Arctic terminal of Sabetta was made in the Arctic winter dark and through thick sea-ice.

Glimpses of the voyage are now put on display by shipping company Sovcomflot and its partner Rosatom.

As previously reported by the Barents Observer, the 299 meter long LNG carrier operated by Sovcomflot on the 27th January set out from the Chinese port and few days later sailed through the Bering Strait were it soon team up with nuclear icebreaker 50 Let Pobedy.

The Christophe de Margerie sails into port of Sabetta on 19th February 2021.

The two ships subsequently sailed together across the vast Arctic route to the Yamal Peninsula.
On the 19th February, the powerful LNG carrier entered the port of Sabetta.
That is two days after the original schedule.

According to shipping company Sovcomflot, the voyage shows that navigation across the eastern sector of the Russian Arctic can be significantly extended.
“The current voyage of Christophe de Margerie significantly expands the navigation window in the in the eastern sector of the Russian Arctic, and confirms that year-round safe navigation is possible along the entire length of the Northern Sea Route,” says company President and CEO Igor Tonkovidov.

The voyage proceeded through thick ice.
The straits between the mainland and archipelagos Severnaya Zemlya and New Siberian Islands are covered by thick fast ice, while the remaining part of the area has one-year old sea-ice that is between 30-200 cm thick.

However, there is no multi-year old ice in the area.

According to Sergey Gen, the captain of the Christophe de Margerie, the ice conditions were the toughest in the Chukchi Sea and the East Siberian Sea, faced by the vessel were ice pressure and ice hummocks in the vessel faced severe ice pressure and ice hummocks.

Through this area, the carrier had to sail astern, Captain Gen said in a comment.
According to Sovcomflot the Christophe de Margerie has sailed astern for about 10 per cent of the time sailed on the Northern Sea Route so far.
 
Links :

Monday, February 22, 2021

Solid sail and mast to be installed for validation in France

Prototype Solid Sail / AeolDrive

From Maritime Executive

French shipyard Chantiers de l’Atlantique is continuing efforts to develop and commercialize its solid sail technology for large ships.

Solid Sail tested on Imoca 60 Yes We Cam with Jean Le Cam skipper / 
photo Bernard Biger, Chantiers de l'Atlantique
 
Developed from an R&D program begun in 2008, the sail is an innovative application of composite materials and a rigging system that has been tested on a smaller scale aboard Jean Le Cam’s sailboat as well in trials with Ponant.
The promising technology has also drawn interest from large ship operators including MSC.
 
As the next step in the technical validation necessary to commercialize the Solid Sail/AeolDrive solution for large ships, the shipyard will install prototypes of the system for testing at the shipyard.
In the fall of 2021, they will install a 125-foot-tall mast that deploys a 550 m² (657 yd²) sail and that will be followed by a full-scale model standing 311 feet in height in 2022 with a 1,200 m² (1,435 yd²) Solid Sail.
The centerpiece of the system, the rigging named AeolDrive – a mast tiltable through 70°, which is a balestron rigging able to rotate through 360° permitting the vessel to remain on course without the maneuvering traditionally required by a sailing ship. 
 
The new test masts will be extending the previous 1 to 5 scale prototype which was tested for two years on a pier in Pornichet harbor.
A system of force and position sensors will enable the aerodynamic and kinematic performances of the assembly to be evaluated while monitoring the stress levels in the mechanical elements.
 
Testing the prototype designs (Chantiers de l'Atlantique)
 
According to the shipyard, the mast will be one of the highest composite masts in the world made of unique carbon fibers. The sail membrane is made of fiberglass with the textile bonds between the panels made of Dyneema (a fiber 15 times as strong as steel).
The unique materials used for the solid sails permit them to be larger than anything possible for the historic fabric sails and the use of rectangular panels facilities the automatic lowering and raising of the sails.
The lifespan of the solid sail is projected to be five times that of conventional sails.
 
Chantiers de l’Atlantique says that the first commercial application for the Solid Sail/AeolDrive solution is destined to a 200 m (655 ft) long cruise ship.These ships will use both sails and an engine for propulsion, achieving a 50 percent reduction in greenhouse gas emissions.
Other applications that they are considering are cargo ships and large pleasure boats.
 
Concept design (Chantiers de l'Atlantique)

The Solid Sail/AeolDrive solution is the fulfillment of a cooperative work between Chantiers de l’Atlantique and its industrial partners.
They are from Brittany (Multiplast, AvelRobotics, SMM Technologies, CDK Technologies, Lorima, G SEA Design, Blew Stoub, Ocean Data System, Pixel Sur Mer and Awentech) for the mast and the sail, and Pays de la Loire (MECA, Wichard, Nov-BLM, Lancelin, Baudin Chateauneuf and PL Marine) for the fitting equipment.
With the support of the regions Brittany and Pays de la Loire and of the local authority of Lorient and Vannes, genuine technological and industrial sectors sprouted around this innovative concept.

Additionally, Solid Sail/AeolDrive received support from the ERDF (European Regional Development Fund), the Pôle Mer Bretagne Atlantique (Brittany Atlantic Sea Pole), and from the PIA (Programme d’Investissement d’Avenir – Investment Program for the Future) operated by ADEME, the French Energy Management Agency, as well as funds from the 2020 European Research and Innovation Program (LeanShips project).

From a scientific and academic point of view, the project was led in association with the TRI Jules Vernes, the ENSTA Bretagne (Grande École of engineering), and the Catholic Institute of Arts and Crafts of the West Coast.

Links :

Sunday, February 21, 2021

Northern islands

The best shots from my trip in the northern islands: Faroe Islands, Lofoten Islands & Senja (Norway). Enjoy aerial views of gorgeous locations:
Vagar, Tindholmur, Kalsoy, Tjornuvik, Henningsvaer, Nusfjord, Reine, Hamnoy, Sakrisoy, Segla…

Saturday, February 20, 2021

Visualizing countries by share of Earth’s surface



From Visual Capitalist by Nicholas LePan
 
There are over 510 million square kilometers of area on the surface of Earth, but less than 30%of this is covered by land.
The rest is water, in the form of vast oceans.
Today’s visualization uses data primarily from the United Nations Statistics Division (UNSD) to rank the world’s countries by their share of Earth’s surface.

Breakdown of Countries Share of Earth’s Surface
 
 
The largest countries by surface area are Russia (3.35%), Canada (1.96%), and China (1.88%).

Together they occupy roughly 7.2% of Earth’s surface.
Russia is so big that even if we divided the country between its Asian and European sections, those new regions would still be the largest in their respective continents.

Antarctica, although not a country, covers the second largest amount of land overall at 2.75%. Meanwhile, the other nations that surpass the 1% mark for surface area include the United States (1.87%), Brazil (1.67%), and Australia (1.51%).

The remaining 195 countries and regions below 1%, combined, account for the other half of Earth’s land surface.
Among the world’s smallest countries are the island nations of the Caribbean and the South Pacific Ocean.
However, the tiniest of the tiny are Vatican City and Monaco, which combine for a total area of just 2.51 km².

The remaining 70% of Earth’s surface is water: 27% territorial waters and 43% international waters or areas beyond national jurisdiction.

Areas Beyond National Jurisdiction

In the past, nations adhered to the freedom-of-the-seas doctrine, a 17th century principle that limited jurisdiction over the oceans to a narrow area along a nation’s coastline.
The rest of the seas did not belong to any nation and were free for countries to travel and exploit.

This situation lasted into the 20th century, but by mid-century there was an effort to extend national claims as competition for offshore resources became increasingly fierce and ocean pollution became an issue.

In 1982, the United Nations adopted the Law of the Sea Convention which extended international law over the extra-territorial waters.
The convention established freedom-of-navigation rights and set territorial sea boundaries 12 miles (19 km) offshore with exclusive economic zones up to 200 miles (322 km) offshore, extending a country’s influence over maritime resources. 

Does Size Matter?

The size of countries is the outcome of politics, economics, history, and geography.
Put simply, borders can change over time.
In 1946, there were 76 independent countries in the world, and today there are 195.
 
There are forces that push together or pull apart landscapes over time.
While physical geography plays a role in the identity of nations, Sheikh Zayed bin Sultan Al Nahyan, the former ruler of UAE, a tiny Gulf nation, put it best:
“A country is not measured by the size of its area on the map. A country is truly measured by its heritage and culture.”

Friday, February 19, 2021

Breaking down the US Navy’s blueprint for a blue Arctic


From Cryopolitics by Mia Bennett


If Russia is the friend that’s been uninvited to America’s Arctic housewarming, China is the new kid on the block that the U.S. seeks to keep out in the cold.

With climate change and an increasingly unstable international order, the U.S. Navy is releasing new strategies at an accelerated pace.
Five years after it published the 2009 Navy Arctic Roadmap, it came out with the Arctic Roadmap: 2014-2030, in step with the Quadrennial Defense Review published that year.
Although the updated roadmap’s title made it seem as if the document were supposed to stick around, five years later, it was replaced by the February 2019 Strategic Outlook for the Arctic.

When asked by reporters why the Navy was already revising its strategy document just four years after its publication and 12 years before its supposed expiry date, retired U.S.
Chief of Naval Operations Admiral John Richardson retorted, “The Arctic triggered it. The damn thing melted.”

Less than two years later, the Navy evidently feels that the situation has changed again enough to warrant yet another update.
Last week, it released its Strategic Blueprint for the Arctic, which replaces the 2019 outlook.
The new blueprint does three main things, which I break down below:
  1. It represents the Arctic as an American homeland rather than frontier, encompassing three oceans stretching from Maine to Alaska
  2. It marks Russia and China as enemies
  3. It portrays the Arctic as a navigable blue ocean rather than an inaccessible frozen periphery
A three-ocean Arctic homeland

The 2019 outlook described America’s Arctic following the definition codified by the 1984 Arctic Research and Policy Act, which encompasses the lands and waters in Alaska north of the Arctic Circle, along the Bering Strait, and in the Aleutians.
The 2019 outlook also used the US Arctic Research Commission’s very basic map of the region, seen below.


The map included in the U.S. Navy’s 2019 Strategic Outlook for the Arctic.

In contrast, the 2021 Strategic Blueprint for the Arctic takes a more expansive view crossing three oceans, from the Atlantic to the Arctic to the Pacific.
The document opens by describing the area encompassing the United States’ Arctic interests: a huge swatch of land and sea “stretching from Maine in the North Atlantic across the Arctic Ocean through the Bering Strait and Alaska in the North Pacific to the southern tip of the Aleutian Island chain.”

It may come as a surprise to see Maine mentioned before Alaska.
For the northeast state, which only began leaning into its Arctic connections a few years ago (once Icelandic shipping company Eimskipbegan regularly calling at the port of Portland), this is a pretty big coup.
The blueprint also directly references Maine’s participation at the annual Arctic Circle conference, which testifies to the Icelandic gathering’s importance for track two Arctic diplomacy.

Despite this geographically more expansive stage-setting, the Navy still acknowledges the same definition of the term “Arctic,” following the 1984 legislation.
However, it now uses a map borrowed from the State Department with a widened scope that captures and labels three oceans – the Atlantic, Arctic, and Pacific – along with the capitals of Russia and Scandinavia.
The eight Arctic Council member states are labeled, too.
So is Maine, representing a small but important edit to the original State Department map.
Finally, while the borders of various Asian countries, including China, remain visible in the 2021 map just like in the ARCUS map included in the 2019 blueprint, the actual countries remain unlabeled.

 
The map included in the 2021 U.S. Navy Strategic Arctic Blueprint.

If the American Arctic is really going to become a home, however, it will need a lot more investment in infrastructure.
In a press conference on January 5, US Navy Secretary Kenneth Braithwaite recounted a recent trip to Adak, Alaska, where he had been stationed as a young pilot.
He remarked, “Unfortunately, it looks like the set from a zombie apocalypse, to be very honest with you. That’s a very harsh environment, it’s been very harsh on the infrastructure there. It would cost an inordinate amount of money to reopen it.”

The Navy thus recognizes that more ports and facilities are needed but doesn’t specify plans for any investments in the blueprint.
Instead, it seems like it will put its energy into improving its posturing, exercises, and fleet synchronization while fretting about the ports that countries like Russia and China are seeking to improve or control.
Meanwhile, the Navy may have to keep relying on other friendly countries’ Arctic infrastructure, as Secretary Braithwaite stressed:
“There are other options that we have to be able to operate out of other airfields in that part of the world, in the Arctic. Of course we have our partnerships with our NATO allies: there’s a new air station opening up in Evenes, Norway, that can support both the P-8 and the Joint Strike Fighter.”
NAVY SECRETARY KENNETH BRAITHWAITE, JANUARY 6, 2021
 
It wouldn’t be America without baseball in this icy field of dreams.
In the photo of the first-ever baseball game at the North Pole played by members of USS Seadragon in August 1960, TM2 SS Thomas J.
Miletich is up at bat while Lt JG Vincent Leahy playing catcher.
Source: National Archives/Mariners Museum
 
From conquering to domesticating the Arctic

The Navy’s interest in sketching out a wider Arctic region—one that protrudes northward not only from Alaska but from the Lower 48, too—supports the force’s effort to transform the Arctic from a frontier into a homeland.
The blueprint mentions the word “frontier” zero times, while it mentions “home” five times.

The apparent domestication of the Arctic was already underway in the Navy’s 2019 outlook, which clearly set out its three strategic objectives for the Arctic as follows:

2019 U.S. Navy Strategic Objectives in the Arctic
  1. Defend U.S. sovereignty and the homeland from attack
  2. Ensuring the Arctic remains a stable, conflict-free region
  3. Preserving freedom of the seas

The Navy’s three strategic objectives in 2019 aligned with the country’s three national security interests expressed in the Department of Defense’s 2019 Arctic Strategy, which define the Arctic in three ways: “as the U.S.
homeland, as a shared region, and as a potential corridor for strategic competition” (here directly mentioning the need to constrain China and Russia).

Now in 2021, the Navy’s three objectives have broadened.
The need to have a presence is expressed in more general terms, while the aim of strengthening naval capabilities has replaced preserving freedom of navigation.

2021 U.S. Navy Objectives in the Arctic
  1. Maintain enhanced presence
  2. Strengthen cooperative partnerships
  3. Build a more capable Arctic naval force

In trying to lay a claim to a wider slice of the Arctic and recast the region as American homeland, the blueprint emphasizes the navy’s historical presence in the region by referencing past expeditions by American explorers and military personnel.
It also makes sure to namedrop not just the white men who led these missions, but their team members, too, whose knowledge was critical to their success.

For instance, the blueprint notes: “Just as [Robert] Peary, a Civil Engineer Corps Officer, led successful Arctic expeditions – together with Matthew Henson, Ootah, Egigingwah, Seegloo, and Ooqueah – this regional blueprint recognizes the long-term challenges and opportunities of a Blue Arctic – and the role of American naval power in.
(No mention is made of the doubt that many historians, including Dennis Rawlins writing in the U.S.
Naval Institute’s Proceedings in 1970, cast on Peary’s claims to being the first at the North Pole in 1909.)
 
 
A photo of the Robert Peary sledge party posing with flags, allegedly at the North Pole, on April 7, 1909 from the National Archives.
The official caption reads, “Ooqueh, holding the Navy League flag; Ootah, holding the D.K.E.
fraternity flag; Matthew Henson, holding the polar flag; Egingwah, holding the D.A.R.
peace flag; and Seeglo, holding the Red Cross flag.”


References to a historical American presence in the Arctic – one that is diverse and inclusive, no less – bolster the narrative that the U.S. has successfully tamed the region and lend confidence to the belief that the U.S.
can maintain an enhanced presence today.
A parallel can be drawn with the conquering and settling of the Western frontier in the nineteenth century, which U.S. historian Frederick Jackson Turner (in)famously declared “closed” in 1890.
By becoming a part of the American homeland, the Arctic no longer represents the enemy to be conquered.
Instead, the country’s northern home has to be defended from new enemies at the doorstep.

Russia: From friend to enemy


In the introduction, immediately after describing America’s Arctic homeland as a region stretching from Maine to Alaska, the blueprint names America’s enemies in the north: Russia and China.
The document posits, “Without sustained American naval presence and partnerships in the Arctic Region, peace and prosperity will be increasingly challenged by Russia and China, whose interests and values differ dramatically from ours.”

The casting of Russia as the enemy is striking given that just a little over a decade ago, the 2009 Navy Arctic Roadmap repeatedly pointed to American naval cooperation with the Russian Navy, Russian Border Guard, the Russian-America Long Term Census of the Arctic Ocean, and the Tiksi Arctic Observatory, located on the Arctic shores of the Russian Far East.
Happier days in 2010 onboard the Russian research vessel Professor Khromov during a joint US-Russia expedition to the Bering Strait.

Read more on the expedition here.

There were peaceful times in the past, too, even if the blueprint overlooks these in favor of a focus on Cold War-era enmity.
The document notes, “Over 150 years ago, USS Jamestown stood our northern watch as the U.S.
flag was raised over Alaska.” Left out of the story is the fact that this historical moment marked the peaceful passing of control over the territory from Russia to the U.S. in Sitka, the former seat of the Russian American Company in Alaska (even if we acknowledge that both empires’ reigns destroyed livelihoods and lifeways for Alaska Natives).
Rather than pay homage to these more cordial times, the blueprint evinces a deep suspicion of Russia’s Arctic activities, which it interprets as a “multilayered militarization of its northern flank.”

This cold and combative description contrasts with depictions of the American Arctic, which use cozier turns of phrase like “our local Alaskan and indigenous communities.” No such language is used to characterize Russia, despite the fact that the ethnic, cultural, and linguistic ties connecting people across the Bering Strait run deep.

(Historical aside: Here are the ship logs from USS Jamestown, including the one on the day it kept watchfrom offshore as the U.S. flag was raised.)

China: A near- non-Arctic state

If Russia is the friend that’s been uninvited to America’s Arctic housewarming, China is the new kid on the block that the U.S. seeks to keep out in the cold.
China – or rather “The People’s Republic of China,” as the blueprint names it, underscoring the bogeyman’s communist status, is described in even harsher terms than Russia.
China is not just undermining global interests and degrading security in the region, as the blueprint claims of Russia.
In fact, China’s growing “economic, scientific, and military reach…presents a threat to people and nations, including those who call the Arctic Region home.” 
I’m left scratching my head as to whether this means the Navy thinks that China would present a threat to Russia, since the latter calls a greater territorial extent of the Arctic home than any other northern nation.

The blueprint’s fixation with China, which it mentions six times (versus Russia’s nine times), is striking – especially seeing as the country was totally absent from the Navy’s 2009 Arctic blueprint.

Consider the international governments and militaries listed then as having an interest in the region:

Japan is the only Asian country listed, and China is nowhere to be found.

While the Navy’s 2021 blueprint doesn’t make any mention of China’s claims to “near-Arctic” statehood (unlike the 2019 Department of Defense’s Arctic Strategy, which actively contested it), the department slipped up in its press release by announcing, “The blueprint places focus on the rising maritime activity spurring from Arctic states, like Russia and China.”

Klaus Dodds, professor of geopolitics at Royal Holloway, University of London, was among the first to catch this mistake.
Puzzled, he wondered, “Did they mean to say this???” The Navy has since corrected what must have been a typo (but at the same time, perhaps a subconscious acknowledgement of the fact that China cannot be overlooked in Arctic relations).

The press release now states, “The blueprint places focus on the rising maritime activity spurring from Arctic and non-Arctic states, like Russia and China, which pos­ture their navies to protect sovereignty and national inter­ests while enabling their ability to project power.”

To nobody’s surprise, the U.S.Navy did not issue an erratum.

Wild blue yonder, tame blue Arctic

Representing the third notable development with regard to the Navy’s shifting perceptions of the Arctic, the blueprint repeatedly uses the phrase “Blue Arctic.” The evolution from white to blue mirrors predictions that over the next two decades, the Arctic region will become increasingly navigable and ice-free.
As a result, the Navy asserts, “Our defense posture must be regularly and rigorously assessed to adapt to a Blue Arctic.”

To adapt, the Navy will seek to grow its presence in the Arctic not only underwater, where its submarines have accumulated over 70 years of experience, but on the increasingly open and accessible surface of the ocean, too.
The Navy aims to achieve this by “regionally posturing our forces, conducting exercises and operations, integrating Navy-Marine Corps-Coast Guard capabilities, and synchronizing our Fleets.”

Massive joint military exercises like ICEX, the U.S. Navy’s biennial “submarine force tactical development and torpedo exercise,” have helped evaluate andenhance American naval preparedness for operations in the Arctic.

Whether the navy can keep up with other countries like Russia and China remains to be seen.
 

Some pretty cool promotional material for ICEX 2018.
See the full brochure here.

Acknowledging the Transpolar Sea Route

Pointing to another central dimension of the blue Arctic, the 2021 blueprint elaborates upon the 2019 strategy’s mentioning of the Transpolar Sea Route, the shipping route via the North Pole that could emerge once sea ice melts sufficiently in summertime in the next two decades.
The blueprint indicates, “The projected opening of a deep-draft trans-polar route in the next 20-30 years has the potential to transform the global transport system.”

As I’ve written about previously on Cryopolitics and in a 2020 paper in Marine Policy, the Transpolar Sea Route would represent the most direct maritime link between Europe and Asia.
It could also facilitate access to new fishing grounds in the Central Arctic Ocean should the 2018 moratorium not be renewed when it expires around 2034.

Cooperating with “like-minded non-Arctic States” from the seafloor to the sky

To prepare for the transformations to an ice-diminished Arctic, the Navy seeks to enhance collaboration with “allies and partners” and the public and private sector.
It’s also open to working with “like-minded non-Arctic States with regional interests” – a categorization that no doubt excludes China, but might include countries like the United Kingdom and the Netherlands.

Importantly, the Navy also strongly supports science, research, and development to defend U.S.
security in the Arctic.
The blueprint reads, “Understanding and predicting the physical environment from sea floor to space, today and for decades, is critical for mission advantage, ensuring the safety of personnel and equipment, and informing future force requirements.”

Defending the virtual homeland with C51SR


It’s not just the physical environment that the Navy deems important to protect: the virtual one is, too.
The blueprint states that the Navy will “assess and prioritize C51SR capabilities in the Arctic.” That’s shorthand for “command, control, communications, computers, cyber, information, surveillance, and reconnaissance” – a mouthful confirming that the world has come a long way from C2, or “command and control.”

The military’s domain awareness in the Arctic is limited by a lack of satellite and terrestrial communications, as a report by the Department of Defense in 2016 warned.
Making investments in remote sensing, ice prediction, and weather forecasting are crucial to closing this gap.
At the same time, the U.S. will likely keep its eye on China, which recently announced that it will launch a new satellite to monitor Arctic shipping routes next year.

Yet enhancing C51SR involves more than just being better able to determine whether the next day will bring snow or sleet.
The U.S. Army rather chillingly describes the term as “technologies that enable information dominance and decisive lethality for the networked Soldier.”

But, not to fret.
The Arctic is America’s homeland, and, as the blueprint reminds, “The United States will always seek peace in the Arctic.”

“The past was alterable.
The past never had been altered.
Oceania was at war with Eastasia.
Oceania had always been at war with Eastasia.”GEORGE ORWELL, 1984
 

Thursday, February 18, 2021

Using whale songs to image beneath the ocean’s floor


image NOAA
 
From Ars Technica by John Timmier

People tend to think of seismic waves as little more than signals of tectonic events, like an earthquake or lava shifting under a volcano.
But these vibrations are also our best way of getting a clear picture of our planet's internal structure.
By watching how the vibrations' paths shift as they encounter different materials, we can get a picture of where different rock layers meet, where rock becomes molten, and more.

In some cases, we get this picture by waiting for a natural event to produce the seismic waves.
In others, we get impatient and set off explosive charges or use a powerful sound-making device.
Today, Václav Kuna and John Nábėlek of Oregon State University are describing yet another option: waiting for a whale to float by.
Using the songs of passing fin whales, the researchers were able to reconstruct the upper layers of the seafloor off the coast of Oregon.
Quite a song

The song of a fin whale is not exactly the sort of thing you'd typically describe as musical.
It's generally in the area of 20Hz, which sounds more like a series of clicks than a continual sound, and the whales produce it in second-long bursts separated by dozens of seconds.
But they are loud.
A guidance on hearing risks places danger at any level above 80 decibels and the loudest concerts as hitting roughly 120 decibels.
A fin whale's song can be in the neighborhood of 190 decibels (although that's in water, which transmits sound differently from the air), and it typically goes on for hours.

As it turns out, the frequency of whale calls is within the range of a bunch of underwater seismographs that researchers had placed on the ocean floor west of the coast of Oregon.
These seismographs sample for signals 100 times every second, so they can easily pick up the song of a fin whale.

And in fact, the equipment had picked up the songs.
By focusing on the calls themselves, Kuna and Nábėlek could track the whales as they went along singing.

The songs they recorded typically went on for hours, during which time the whales cruised through the area at a rate of between 4 and 10 kilometers an hour.
This meant that the song-filled trips ranged from 15 to 40 kilometers.
During these trips, each individual whale produced anywhere from 200 to 500 individual bursts that could be picked up by the seismographs.

But the whale's songs don't only reach the seismographs by a direct route.
Some of the sound waves get there after bouncing off the ocean's surface or floor—and some of them bounce between the two more than once.
Others hit the ocean floor and then bounce off the different layers of material below it.
All of them reach the instrument at different times within the 40-second window between each individual sonic element of the song.
 

The echoes created by a fin whale are rather complicated.
Kuna and Nábelek


Reconstructing the exact details of which signals arise, and when, is complicated, to put it mildly.
But earth science researchers have a great deal of experience with this sort of thing.
Waves that take certain paths require enough physical space between the whale and the seismometer to undergo all the reflections involved.
So certain elements are cut off when the whale gets closer than 12 kilometers, and another set cut out at 4 kilometers.

By piecing these details together, Kuna and Nábėlek were able to figure out the thickness of the sediment layer, a layer formed by lava flows below that, and more robust volcanic rock below that.
The seismometers were even sensitive enough to register differences in the amount of sediment, which ranged from 400 to 650 meters thick, that had built up.

Overall, the resolution wasn't as good as you'd get with human-triggered sound sources from the surface of the water.
But critically, you don't need an actual boat above the seismograph array to get data.
That's not a huge limitation for a specific study, but there are probably a lot more underwater sensors out there than there are people intentionally making seismic waves for them to pick up.
And fin whales have a global range, so there's likely to be a few around.

There are areas with a complicated topography—meaning lots of lumps on the ocean's floor—where reading whale song probably wouldn't be all that effective.
But the researchers behind this work think they can probably boost the resolution by using a different whale with a higher-frequency song.
They specifically suggest that sperm whales would probably do the trick.

Links :

Wednesday, February 17, 2021

Global salmon farming harming marine life and costing billions in damage


Fish mortality has more than quadrupled, from 3% in 2002 to about 13.5% in 2019, in Scottish salmon farms alone.
Photograph: Robert F Bukaty/AP


From The Guardian by Fiona Harvey

Report says pollution, parasites and fish mortality rates cost an estimated $50bn globally from 2013 to 2019


Salmon farming is wreaking ruin on marine ecosystems, through pollution, parasites and high fish mortality rates which are causing billions of pounds a year in damage, a new assessment of the global salmon farming industry has found.

Taken together, these costs amounted to about $50bn globally from 2013 to 2019, according to a report published on Thursday.

Fish mortality has more than quadrupled, from 3% in 2002 to about 13.5% in 2019, in Scottish salmon farms alone.
About a fifth of these deaths are recorded as being due to sea lice infestations, but about two thirds are unaccounted for so the real mortality owing to sea lice – which feed on salmon skin and mucus, effectively eating the fish alive – could be much higher.

Scotland is one of the biggest producers of farmed salmon in the world, with the industry worth an estimated £2bn a year to the Scottish economy.
But the costs in environmental terms alone were reckoned to be £1.4bn from 2013 to 2019, by Just Economics, which carried out the research for the report, entitled Dead Loss, for the Changing Markets Foundation campaigning organisation.

The sheer quantity of wild fish used in salmon farms is also a growing concern.
About a fifth of the world’s annual wild fish catch, amounting to about 18m tonnes of wild fish a year, is used to make fishmeal and fish oil, of which about 70% goes to fish farms.
This is causing problems for fishers in developing countries, who are seeing their stocks depleted in order to feed western consumption of farmed fish, according to the report.

Key species such as sardines in west Africa are now heavily overfished for this purpose, and this situation is likely to deteriorate further as fish farmers plan substantial expansion in the coming years.
Scotland alone plans to double its farming capacity by 2030, while Norway expects a fivefold increase by 2050, according to the report.

 
Salmon farmers could use oils from algae as a source of Omega 3 for their farmed fish, to replace fish oil from wild fish, but few do so, according to the report.
Natasha Hurley, campaigns manager at the Changing Markets Foundation, told the Guardian: “Moving away from using wild caught fish in food would make salmon farming more sustainable, as it is having a huge impact on wild fish.”

She said consumers were often unaware of what they were buying, as fish is poorly labelled in UK supermarkets and its farmed origin is often not obvious.
She called on governments to tighten the rules on licensing fish farms, to enforce lower stocking density on farms, and to improve labelling.

The report also examined the salmon farming industry in Canada, Norway and Chile, the other biggest global producers.
It found that of the costs associated with fish farming, about 60% were borne by the producers, especially in the form of fish mortality and the cost of treating sea lice, but about 40% of the costs were borne by wider society, for instance in pollution, loss of fish populations and the impacts on the climate crisis.

Mowi, a Norwegian company, produces a fifth of the world’s farmed Atlantic salmon, and is named in the report as showing 50m premature fish deaths from 2010 to 2019, at a cost of about $1.7bn.
A spokesperson for the company said: “We are pleased that the report finds that, when considering the full range of benefits and impacts, the business of salmon farming demonstrates overall positive benefit.
We agree that there are opportunities for continued improvements for our business.
The inclusion of small amounts of fish meal and oil in our salmon’s diet is certified sustainable by third parties and integral to a salmon’s health and welfare.”

A spokesperson for the Scottish Salmon Producers Organisation said: “Farmed salmon has a great environmental story to tell – it has the lowest carbon footprint of any main livestock protein, it is a nutritious and healthy food and, as the UN and other international experts have acknowledged, aquaculture provides one of the best solutions to feeding the world’s burgeoning population in the years to come.
It is a shame that the authors have chosen to ignore these undeniable benefits when publicising this report.”

Links :