Tuesday, November 15, 2016

‘We couldn’t believe our eyes’: A lost world of shipwrecks is found

An image of the well-preserved medieval ship found at the bottom of the Black Sea, one of more than 40 wrecks discovered.
Photogrammetry, a process using thousands of photographs and readings, produced a rendering that appears three-dimensional.
Credit Expedition and Education Foundation/Black Sea MAP

From New York Times by William J. Broad

The medieval ship lay more than a half-mile down at the bottom of the Black Sea, its masts, timbers and planking undisturbed in the darkness for seven or eight centuries.
Lack of oxygen in the icy depths had ruled out the usual riot of creatures that feast on sunken wood.
This fall, a team of explorers lowered a robot on a long tether, lit up the wreck with bright lights and took thousands of high-resolution photos.
A computer then merged the images into a detailed portrait.
Archaeologists date the discovery to the 13th or 14th century, opening a new window on forerunners of the 15th- and 16th-century sailing vessels that discovered the New World, including those of Columbus.
This medieval ship probably served the Venetian empire, which had Black Sea outposts.
Never before had this type of ship been found in such complete form.
The breakthrough was the quarterdeck, from which the captain would have directed a crew of perhaps 20 sailors.

“That’s never been seen archaeologically,” said Rodrigo Pacheco-Ruiz, an expedition member at the Center for Maritime Archaeology at the University of Southampton, in Britain.
“We couldn’t believe our eyes.”

 A photogrammetric image of a ship from the Ottoman era that most likely went down between the 17th and 19th centuries.
The discoverers nicknamed it the Flower of the Black Sea because of its ornate carvings, including two large posts topped with petals.
Credit Expedition and Education Foundation/Black Sea MAP

Remarkably, the find is but one of more than 40 shipwrecks that the international team recently discovered and photographed off the Bulgarian coast in one of archaeology’s greatest coups.
In age, the vessels span a millennium, from the Byzantine to the Ottoman empires, from the ninth to the 19th centuries.
Generally, the ships are in such good repair that the images reveal intact coils of rope, rudders and elaborately carved decorations.
“They’re astonishingly preserved,” said Jon Adams, the leader of the Black Sea project and founding director of the maritime archaeology center at the University of Southampton.
Kroum Batchvarov, a team member at the University of Connecticut who grew up in Bulgaria and has conducted other studies in its waters, said the recent discoveries “far surpassed my wildest expectations.”
Independent experts said the annals of deepwater archaeology hold few, if any, comparable sweeps of discovery in which shipwrecks have proved to be so plentiful, diverse and well preserved.

 A photogrammetric image of the stern of the Ottoman-era ship showing coils of rope and a tiller with elaborate carvings.
A lack of oxygen at the icy depths of the Black Sea left the wrecks relatively undisturbed.
Credit Expedition and Education Foundation/Black Sea MAP

“It’s a great story,” said Shelley Wachsmann of the Institute of Nautical Archaeology at Texas A&M University.
“We can expect some real contributions to our understanding of ancient trade routes.”
Goods traded on the Black Sea included grains, furs, horses, oils, cloth, wine and people.
The Tatars turned Christians into slaves who were shipped to places like Cairo.
For Europeans, the sea provided access to a northern branch of the Silk Road and imports of silk, satin, musk, perfumes, spices and jewels.
Marco Polo reportedly visited the Black Sea, and Italian merchant colonies dotted its shores.
The profits were so enormous that, in the 13th and 14th centuries, Venice and Genoa fought a series of wars for control of the trade routes, including those of the Black Sea.
Brendan P. Foley, an archaeologist at the Woods Hole Oceanographic Institution on Cape Cod, Mass., said the good condition of the shipwrecks implied that many objects inside their hulls might also be intact.
“You might find books, parchment, written documents,” he said in an interview.
“Who knows how much of this stuff was being transported? But now we have the possibility of finding out. It’s amazing.”

Experts said the success in Bulgarian waters might inspire other nations that control portions of the Black Sea to join the archaeological hunt.
They are Georgia, Romania, Russia, Turkey and Ukraine.
Dr. Foley, who has explored a number of Black Sea wrecks, said the sea’s overall expanse undoubtedly held tens of thousands of lost ships.
“Everything that sinks out there is going to be preserved,” he added.
“They’re not going away.”
For ages, the Black Sea was a busy waterway that served the Balkans, the Eurasian steppes, the Caucasus, Asia Minor, Mesopotamia and Greece.
It long beckoned to archaeologists because they knew its deep waters lacked oxygen, a rarity for large bodies of water.
The great rivers of Eastern Europe — the Don, the Danube, the Dnieper — pour so much fresh water into the sea that a permanent layer forms over denser, salty water from the Mediterranean.
As a result, oxygen from the atmosphere that mixes readily with fresh water never penetrates the inky depths.
In 1976, Willard Bascom, a pioneer of oceanography, in his book “Deep Water, Ancient Ships,” called the Black Sea unique among the world’s seas and a top candidate for exploration and discovery.

A photogrammetric image of a Byzantine wreck, dating perhaps to the ninth century.
Superimposed is an image of one of the expedition’s tethered robots that photographed the lost ships. 
Credit Expedition and Education Foundation/Black Sea MAP

“One is tempted,” he wrote, “to begin searching there in spite of the huge expanse of bottom that would have to be inspected.”
In 2002, Robert D. Ballard, a discoverer of the sunken Titanic, led a Black Sea expedition that found a 2,400-year-old wreck laden with the clay storage jars of antiquity. One held remnants of a large fish that had been dried and cut into steaks, a popular food in ancient Greece.
The new team said it received exploratory permits from the Bulgarian ministries of culture and foreign affairs and limited its Black Sea hunts to parts of that nation’s exclusive economic zone, which covers thousands of square miles and runs up to roughly a mile deep.
Although the team’s official name is the Black Sea Maritime Archaeology Project, or Black Sea MAP, it also hauls up sediments to hunt for clues to how the sea’s rising waters engulfed former land surfaces and human settlements.
Team members listed on its website include the Bulgarian National Institute of Archaeology, the Bulgarian Center for Underwater Archaeology, Sodertorn University in Sweden, and the Hellenic Center for Marine Research in Greece.

An illustration of what the research team believes the medieval ship found in the Black Sea looked like during its heyday.Credit Jon Adams/University of Southampton/Black Sea MAP

The project’s financial backer is the Expedition and Education Foundation, a charity registered in Britain whose benefactors want to remain anonymous, team members said.
Dr. Adams of the University of Southampton, the team’s scientific leader, described it as catalyzing an academic-industry partnership on the largest project “of its type ever undertaken.”

Nothing is known publicly about the cost, presumably vast, of the Black Sea explorations, which are to run for three years.
The endeavor began last year with a large Greek ship doing a preliminary survey.
This year, the main vessel was the Stril Explorer, a British-flagged ship bearing a helicopter landing pad that usually services the undersea pipes and structures of the offshore oil industry.

Instead, archaeologists on the ship lowered its sophisticated robots to hunt for ancient shipwrecks and lost history.
In an interview, Dr. Pacheco-Ruiz of the University of Southampton said he was watching the monitors late one night in September when the undersea robot lit up a large wreck in a high state of preservation.
“I was speechless,” he recalled.
“When I saw the ropes, I couldn’t believe my eyes. I still can’t.”

Dr. Pacheco-Ruiz said the vessel hailed from the Ottoman Empire, whose capital was Constantinople (today Istanbul), and most likely went down sometime between the 17th and 19th centuries.
He said the team nicknamed it “Flower of the Black Sea” because its deck bears ornate carvings, including two large posts with tops that form petals.
In an interview, Dr. Batchvarov of the University of Connecticut said most of the discoveries date to the Ottoman era.
So it was that, late one night, during his shift, he assumed that a new wreck coming into view would be more of the same.
“Then I saw a quarter rudder,” he recalled, referring to a kind of large steering oar on a ship’s side. It implied the wreck was much older.
Then another appeared. Quickly, he had the expedition’s leader, Dr. Adams, awakened.
“He came immediately,” Dr. Batchvarov recalled.
“We looked at each other like two little boys in a candy shop.”
Dr. Batchvarov said the wreck — the medieval one found more than a half-mile down — was part of a class known by several names, including cocha and “round ship.”
The latter name arose from how its ample girth let it carry more cargo and passengers than a warship.

Dr. Adams said the remarkable color images of the lost ships derived from a process known as photogrammetry.
It combines photography with the careful measurement of distances between objects, letting a computer turn flat images into renderings that seem three-dimensional.
He said tethered robots shot the photographic images with video and still cameras.
The distance information, he added, came from advanced sonars, which emit high-pitched sounds that echo through seawater.
Their measurements, he said, can range down to less than a millimeter.
A news release from the University of Southampton refers to the images as “digital models.”
Their creation, it said, “takes days even with the fastest computers.”
Filmmakers are profiling the Black Sea hunt in a documentary, according to the team’s website.
Another part of the project seeks to share the thrill of discovery with schools and educators.
Students are to study on the Black Sea, the website says, or join university scientists in analyzing field samples “to uncover the mysteries of the past.”
The team has said little publicly on whether it plans to excavate the ships — a topic on which nations, academics and treasure hunters have long clashed.
Bulgaria is a signatory to the 2001 United Nations convention that outlaws commercial trade in underwater cultural heritage and sets out guidelines on such things as artifact recovery and public display.
Dr. Pacheco-Ruiz said the team had so far discovered and photographed 44 shipwrecks, and that more beckoned.
Which was the most important?
Dr. Adams said that for him, a student of early European shipbuilding, the centerpiece was the medieval round ship.
He said it evoked Marco Polo and city states like Venice.
The ship, he added, incorporated a number of innovations that let it do more than its predecessors had and paved the way for bigger things to come.
“It’s not too much,” he said, “to say that medieval Europe became modern with the help of ships like these.”

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Monday, November 14, 2016

We’re about to see a record-breaking supermoon - the biggest in nearly 70 years


From Science Alert

If you only see one astronomical event this year, make it the November supermoon, when the Moon will be the closest to Earth it’s been since January 1948.
During the event, which will happen on the eve of November 14, the Moon will appear up to 14 percent bigger and 30 percent brighter than an average full moon.
This is the closest the Moon will get to Earth until 25 November 2034, so you really don’t want to miss this one.


So how do you get a supermoon?

As NASA explains, because the Moon has an elliptical orbit, one side - called the perigee - is about 48,280 km (30,000 miles) closer to Earth than the other side (the apogee).
When the Sun, the Moon, and Earth line up as the Moon orbits Earth, that’s known as syzygy (definitely something you want to keep in your back pocket for your next Scrabble match).
When this Earth-Moon-Sun system occurs with the perigee side of the Moon facing us, and the Moon happens to be on the opposite side of Earth from the Sun, we get what’s called a perigee-syzygy.
That causes the Moon to appear much bigger and brighter in our sky than usual, and it’s referred to as a supermoon - or more technically, a perigee moon.
Supermoons aren’t all that uncommon - we just had one on October 16, and after the November 14 super-supermoon, we’ll have another one on December 14.


But because the November 14 Moon becomes full within about 2 hours of perigee, it’s going to look the biggest it has in nearly seven decades.
"The full moon of November 14 is not only the closest full moon of 2016, but also the closest full moon to date in the 21st century," says NASA.
"The full moon won’t come this close to Earth again until 25 November 2034."
Depending on where you're viewing it from, the difference between a supermoon and a regular full moon can be stark, or difficult to tell.
If the Moon is hanging high overhead, and you have no buildings or landmarks to compare it to, it can be tricky to tell that it's larger than usual.
But if you're viewing from a spot where the Moon is sitting closer to the horizon, it can create what's known as 'moon illusion'.
"When the moon is near the horizon, it can look unnaturally large when viewed through trees, buildings, or other foreground objects," says NASA.
"The effect is an optical illusion, but that fact doesn’t take away from the experience."


If you're planning on viewing the November 14 supermoon, be sure to get somewhere nice and dark, away from the lights of the city, if you can.
You'll have some awesome opportunities to take pictures with your phone overnight, but if you want to see it at its absolute biggest, it's expected to reach the peak of its full phase on the morning of November 14 at 8:52am EST (1352 GMT).
For those of you in Australia, you'll need to wait until November 15 to see it, and the Moon will hit its full phase at 12:52am AEST.

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Sunday, November 13, 2016

The importance of Maritime Surveillance


The Swordfish MPA is a high-end, multi-role safeguard platform
that offers strategic ISR capabilities over both sea and land.

Saturday, November 12, 2016

Solo the Americas : Matt Rutherford solo sailing

Once labeled a “youth-at-risk,” 30-year old Matt Rutherford risked it all in an attempt to become the first person to sail alone, nonstop around North and South America.
www.solotheamericas.org 

In June 2011, Matt departed on an incredible, death-defying voyage to sail nonstop around the Americas. On St Brendan, Albin Vega #1147, an old, scrappy 27-foot sailboat he spent the next 309 days alone at sea.
He braved the icebergs of the Arctic and the treacherous waters off Cape Horn.

Red Dot on the Ocean is the story of Matt's death-defying voyage
and the childhood odyssey that shaped him

Friday, November 11, 2016

Image of the week : Offshore wind farms make wakes

acquired June 30, 2015

From NASA (Landsat)

For at least the past decade, satellites have spotted white dots cropping up in the North Sea.
If viewed from Earth’s surface, you would see that these dots are actually wind turbines—huge arrays of towers rising from the sea and topped with electricity-generating rotors.

 Kentish Flat wind farm with the GeoGarage platform (UKHO chart)

But they’re doing more than harvesting the wind.
They appear to also be giving rise to sediment plumes.

 acquired June 30, 2015

Some of the North Sea’s most expansive arrays are visible in these images, acquired on Jun 30, 2015, with the Operational Land Imager (OLI) on the Landsat 8 satellite.
When these images were acquired, there were 84 offshore wind farms in Europe (including some under construction).
The North Sea accounts for the most offshore wind capacity—69 percent—in European seas, followed by the Irish Sea and Baltic Sea.

 acquired June 30, 2015

The turbines were built to take advantage of high winds blowing over the North Sea’s surface.
The London Array, visible in the first detailed image, spans 100 square kilometers (40 square miles). The wind farm, which first became operational in 2013, sits on two natural sandbanks in water as deep as 25 meters (80 feet).
The site was chosen because of its proximity to onshore electric power infrastructure and because it is beyond the main shipping lanes through the area.

 Thanet wind farm with the GeoGarage platform (UKHO chart)

Other significant wind farms, Thanet and the northern half of Greater Gabbard, are shown in the second and third detailed images.
Thanet spans 35 square kilometers (14 square miles) and sits in water measuring 20 to 25 meters deep; the entirety of Greater Gabbard spans 147 square kilometers (57 square miles) and sits in water 24 to 34 meters deep.

 acquired June 30, 2015

 Greater Gabbard wind farm with the GeoGarage platform (UKHO chart)

But the environment below the water’s surface can also feel the presence of the turbines.
The detailed views reveal light-brown plumes of suspended sediments extending from each tower.
In a 2014 paper, researchers analyzed satellite imagery and found that the wakes (and plumes) can measure anywhere from 30 to 150 meters wide and up to several kilometers long.
“The fact that the wakes are browner than the surrounding waters shows that they contain more suspended sediments,” said Quinten Vanhellemont, a researcher at the Royal Belgian Institute of Natural Sciences and lead author of the 2014 paper.
“This shows that the installation of the wind turbines not only modifies the wind field above the sea surface (which is expected as they are extracting wind energy), but that they also modify the currents and sediment transport in the water.”

 London array wind farm with the GeoGarage platform (UKHO chart)

Vanhellemont explained that the wakes are generated by the tidal current moving around the foundation of the turbine.
The direction and curvature in the wakes are related to the general direction of the current.
For example, the image of the London Array was acquired during flood tide, so the wakes follow the northward current.
But the tide in this area reverses every six hours, Vanhellemont said, “so the wakes are quite dynamic over the day.”
It’s not yet clear how these changes in sediment transport could affect the relatively shallow underwater environment, which is known to be an important fish nursery.
According to Vanhellemont, researchers at the University of Hull are currently studying the wakes in greater detail by investigating their 3D structure.

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