Friday, October 6, 2017

Image of the week : A-68 Adrift

acquired September 16, 2017
 
From NASA

A lot happened on the Antarctic Peninsula under the cloak of the 2017 polar night—most notably, the calving of a massive iceberg from the Larsen C ice shelf.
At the time (July), scientists had to rely on thermal imagery and radar data to observe the break and to watch the subsequent motion of the ice.
By August, scientists started getting their first sunlit views of the new iceberg, which the U.S. National Ice Center named A-68.

An animation of the progress of A-68A and A-68B, since they emerged from polar night.
After initially rocking back and forth in the cavity it formed at the end of Larsen C, A-68 has since drifted away from the ice shelf, with the gap in between being filled with mélange - smaller chunks of ice that broke off from the edges of A-68A and the face of the ice shelf, mixed with sea ice that slipped in as the larger iceberg moved farther out. 
Credit: NASA/Aqua MODIS/Scott Sutherland
(other animated picture from ESA)

The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured a wide view of the berg on September 11.
A few days later, on September 16, the Operational Land Imager (OLI) and the Thermal Infrared Sensor (TIRS) on Landsat 8 captured these detailed images.
The image on the left shows the icebergs in natural color.
The rifts on the main berg and ice shelf stand out, while clouds on the east side cast a shadow on the berg.
The thermal image on the right shows the same area in false-color.
Note that the clouds over the ice shelf do not show up as well in the thermal image because they are about the same temperature as the shelf.
Thermal imagery has the advantage of showing where the colder ice ends and “warm” water of the Weddell Sea begins.
It also indicates differences in the thickness of ice types.
For example, the mélange is thicker (has a colder signal) than the frazil ice, but thinner (warmer signal) than the shelf and icebergs.

Larsen Ice Shelf, Released 06/10/2017 10:00 am
Copyright contains modified Copernicus Sentinel data (2017), processed by ESA
The Copernicus Sentinel-3A satellite takes us over the Antarctic Peninsula and the adjacent Larsen Ice Shelf, from which a massive iceberg broke off in July.
The image has been manipulated, so clouds appear pink while snow and ice are blue to help us differentiate between them.
The only land clearly visible is the tip of the Peninsula in the upper left, while sea ice covers the Weddell Sea to the right.
Captured on 25 September, the image shows the iceberg near the centre.
The A68 berg had been jostling back and forth against the ice shelf, but more recent satellite imagery revealed that the gap between the berg and the shelf is widening – possibly drifting out to sea.
An iceberg’s progress is difficult to predict.
It may remain in the area for decades, but if it breaks up, parts may drift north into warmer waters. Since the ice shelf is already floating, this giant iceberg does not influence sea level.
A68 is about twice the size of Luxembourg and with its calving has changed the outline of the Antarctic Peninsula forever – about 10% of the area of the Larsen C Ice Shelf has been removed.
The loss of such a large piece is of interest because ice shelves along the peninsula play an important role in ‘buttressing’ glaciers that feed ice seawards, effectively slowing their flow.
Previous events further north on the Larsen A and B shelves, captured by ESA’s ERS and Envisat satellites, indicate the flow of glaciers behind can accelerate when a large portion of an ice shelf is lost, contributing to sea-level rise. 

Both images show a thin layer of frazil ice, which does not offer much resistance as winds, tides, and currents try to move the massive iceberg away from the Larsen C ice shelf.
In a few weeks of observations, scientists have seen the passage widen between the main iceberg and the front of the shelf.
This slow widening comes after an initial back-and-forth movement in July broke the main berg into two large pieces, which the U.S. National Ice Center named A-68A and A-68B.
The collisions also produced a handful of pieces too small to be named.

The primary reason for A-68 drifting away from Larsen C is apparently winds blowing off the ice shelf, which forced sea ice farther into the Welland Sea, opening up an area for A-68 to move into.
The motion of the iceberg, after this, will depend on how the sea ice moves and melts as the south polar region progresses into spring.

acquired September 16, 2017

One unnamed iceberg, shown in detail above, has been drifting northward in the passage since the break.
Notice how the edges of this piece appear much sharper than the edges of the shelf or A-68A.
Those edges have already been rounded by blowing snow and gravity, but the smaller piece has been battered and reshaped by recent collisions, resulting in its highly defined edges.

 Sentinel-1 (02-10-2017)

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Thursday, October 5, 2017

The US Navy has created its first ever underwater drone squadron


From The Drive by Joseph Trevithick

The service expects to have fully operational units specifically for unmanned undersea missions by 2020.

The U.S. Navy has created its first ever dedicated underwater drone unit, Unmanned Undersea Vehicle Squadron One, or UUVRON 1, splitting it off from a secretive submarine unit in the process.
The decision highlights the steadily growing importance of unmanned craft within the service, which hopes to have dedicated operational unmanned undersea elements by the end of the decade, and across the U.S. military in general.

The Navy formally activated UUVRON 1 at a ceremony at the Naval Undersea Warfare Center in Keyport, Washington.
At the same time, the new organization replaced a smaller detachment that had been part of Submarine Development Squadron Five (DEVRON 5).
This unit still contains a variety of unique elements, including the USS Jimmy Carter spy sub, which recently returned from a shadowy, but apparently successful mission, as well as the Detachment Undersea Research and Development, which has been associated with those covert activities in the past.

“Today we are transitioning our UUV detachment into the first UUV squadron,” U.S.
Navy Captain Robert Gaucher, the outgoing head of DEVRON 5 said during the event.
“Why is this historical? It's because in standing up UUVRON 1, it shows our Navy's commitment to the future of unmanned systems and undersea combat.”

The previous Detachment Unmanned Undersea Vehicles was already a relatively young unit.
It only received its first underwater drone, a torpedo shaped vehicle known as a Large Training Vehicle 38, in August 2014.




USN The Large Training Vehicle 38.

“This is certainly a key milestone,” U.S. Navy Lieutenant Brian Nuss, then the officer in charge of the detachment, said at the time.
“The future large-diameter vehicles will come in 2020 and in order for the detachment to fully prepare for the delivery of those vehicles we have to start with the tactics, training and procedures now to make it a successful program in the future.”

The implication here would be that, at least for a period, the Navy planned for UUVRON 1 to reach its full operational capability at some point in 2020.
It is possible that the service may be able to get the squadron fully up and running sooner, depending on how the state of the training pipeline to staff the necessary slots and what additional equipment it needs to acquire.

Another possibility is that UUVRON 1 will continue to focus on research and development and test evaluation, while the Navy works to establish operational unmanned undersea units.
It could be those organizations that the service expects to be ready to go by 2020.

Whatever the case, the capability is important and it’s a long time coming.
By 2020, the Navy will have spent two decades working on achieving the broad goals outlined in its unmanned undersea vehicle master plans.


USN Sailors prepare to deploy a King Fish counter-mine drone.

The service published the first of these white papers in 2000 and issued a new version in 2004.
Seven years later, Seapower Magazine reported there was another updated document, but that it was classified.
“We actually have action plans on all the missions we are trying to achieve,” U.S. Navy Rear Admiral Matthew Klunder, then the director of intelligence, surveillance and reconnaissance capabilities within the Navy’s Information Dominance unit, told Seapower about the new plan.
It “covers every spectrum,” from a military missions, such as mine hunting and surveillance, to humanitarian assistance and research roles.

It’s very likely that some of all of the missions in the 2011 roadmap were the same or similar to the nearly a dozen roles outlined in the 2004 document, which is publicly available.
Some of these were intelligence gathering, time critical strike, anti-mine warfare, anti-submarine warfare, communication relaying, and force protection against enemy special operations forces and combat divers and terrorists.
In addition, the Navy said it could be possible that a final unmanned undersea vehicle design could be modular, able to carry a number of payloads, including expendable weapons or remote sensors, depending on the needs of the mission.


A graphic discussing possible underwater drone payloads from the US Navy's 2004 roadmap.

In a speech on Feb. 3, 2016, and in line with the so-called “Third Offset” strategy to stay technologically ahead of potential enemies, then Secretary of Defense Secretary Ashton Carter said the U.S. military as a whole would be investing $600 million in a variety of unmanned undersea systems.
It’s “a new capability you’ll be seeing a lot more of” and would be part of larger plans for “making our ships and aircraft work together in ways that they haven’t before but technology makes possible,” he told sailors during the event in San Diego, California.

This suggested a significant increase over the Navy’s budgeting at the time.
In the fiscal year 2016 budget proposal, the service asked for just shy of $5 million for various undersea drone projects, less than five percent of the annual expenditure Carter was suggesting.

At present, the majority of the Navy’s existing underwater drones fall into one of two categories, either being focused on mine hunting or employed in oceanographic mapping and research roles.
In a bizarre episode in December 2016, members of China’s People’s Liberation Army Navy (PLAN) snatched one of the latter vehicles, commonly known as gliders, out of the water in the South China Sea, before unceremoniously returning it days later.

Underwater glider research is currently underway in the physics department at the naval postgraduate in Monterey Ca.
Dr. Kevin Smith is a specialist in underwater acoustics and sonar systems.
He and his team are currently focused on autonomous underwater gliders and developing systems capable of detecting parameters in the ocean and listening for various sources of sound.

The benefits in both of these cases are relatively clear cut.
Gliders can help gather information about the ocean and sea floor faster and cheaper than sailing a large research vessel along the same routes.
It is possible that they may be able to get into areas that would be too shallow or narrow for a larger ship, as well.
They are far more persistent than a manned vessel as well, allowing for collection of data over a far larger timeframe.

When it comes to mines, on land or at sea, using a remote sensor of some kind to identify an object help keeps personnel away from danger.
A drone can move in very close to an object to examine it with relatively little risk and possibly disarm it without having to send out a specialized team.
All of this helps commanders maneuver safely through potentially contested and congested waterways.
Naval mines, including improvised ones that non-state actors are crafting, are a serious threat to both commercial shipping and naval vessels.


USN Sailors release a Swordfish mine-hunting underwater drone.

At the same time, the Navy is working on a so-called Large Displacement Unmanned Undersea Vehicle (LDUUV), as part of a program known as Snakehead.
Detachment Unmanned Undersea Vehicles’s Large Training Vehicle 38 had been a surrogate for this vehicle, the first prototypes of which are expected to be in the water by 2019, according to USNI News.

Not surprisingly, UUVRON 1 is slated to receive the first experimental LDUUV.
There are also future plans for extra large systems that could operate as either a remote controlled or autonomous mini-submarine or even have the ability to be optionally manned if need be.
In 2015, a team of Huntington Ingalls Underwater Solutions Group, Bluefin Robotics, and Battelle demonstrated on such vehicle Proteus.
The next year, Boeing showed off the huge Echo Voyager, claiming it could operation underwater for up to six months.

There's no real definitive idea of what these vehicles might look like in the end, those most of the notional concepts are shaped like little subs.
In 2014, though, the U.S. Navy showed off a underwater drone that looked and moved like a shark.

The GhostSwimmer vehicle developed by the Chief of Naval Operations' Rapid Innovation Cell (CRIC) project Silent NEMO undergoes testing during an event at Joint Expeditionary Base Little Creek - Fort Story.
Project Silent NEMO is an experiment to explore the possible uses for a biomimetic device developed by the Office of Naval Research.

As of earlier in 2017, the Office of Naval Research was working on an unmanned flying craft that could hit the water and then turn into a subsurface vehicle, though purely as a proof of concept.
A number of private companies are also working on similar convertible water craft that are both manned and unmanned.


The Office of Naval Research's Flying Sea Glider. Joseph Trevithick


Whatever it looks like, the Navy’s initial goal for the final Snakehead is a design that can conduct a variety of intelligence, surveillance, and reconnaissance functions.
This could include gathering intelligence on enemy ships or facilities ashore, patrolling waterways for items of interest, or gathering information about a body of water, beach, or other landing side ahead of an attack naval or amphibious operation.

Again, the benefit of a using a drone for these functions it that it offers a lower cost and reduced risk option, especially when attempting to gather information about heavily defended or otherwise restricted areas.
With regards to unmanned undersea vehicles, it also reduces the burden on larger submarines, allowing them to focus on higher priority missions that requirement their more expansive intelligence gathering and weapon systems.

The option to use a unmanned vehicle for these jobs will likely only become more important in the coming years, as well.
Though we at The War Zone more often talk about concepts such as “anti-access and area denial” in terms of integrated air defense networks, many of the U.S. military’s potential opponents are exploring similar arrangements at sea.

In May 2017, the People's Liberation Army Navy (PLAN) said it was beginning construction of an expansive sensor net in the South China Sea for “environmental” purposes.
Of course, these nodes could just as easily end up configured to keep watch for submarines and in a conflict, it would be especially useful to be able to find the exact locations of the nodes and attempt to size up their capabilities without risking detection in a manned boat in the process.

The Navy takes a trip under the sea to test its newly developed Common Control System (CCS) with a submersible unmanned vehicle at the Naval Undersea Warfare Center Keyport in Puget Sound, Washington.
Learn how data collected from this series of successful underwater missions will help operators eliminate redundant efforts and reduce cost when operating unmanned vehicles in sea, land or air.

Further versions of Snakehead could carry actual weapons or electronic warfare payloads, to disable underwater sensors and mines or attack other undersea vessels, surface ships, or targets on land, depending on the final configuration.
Though not mentioned specifically, it is possible that multiple LDUUVs could operate as a single swarm to confuse, distract, or overwhelm enemy defenses, or operate in combination with small underwater drones for that purpose.
Networked together and connected to manned submarines, surface ships, or even aircraft, one or more of these unmanned underwater craft could just extend the situational awareness for the whole group along a broad front.

“I can think of so many missions that unmanned systems can help out,” U.S. Navy Rear Admiral Robert Girrier, then Director of Unmanned Warfare Systems within the Navy’s top Unmanned Systems Office, said during a talk at the Center for Strategic and International Studies in February 2016.
Citing a desire for unmanned systems to be more of an integral part of operations in general, U.S. Navy Rear Admiral Mike Manazir, then Deputy Chief of Naval Operations for Warfare Systems, shut down the office, also known as N99, in January 2017.

Exactly what sort of systems and tactics will work or not is likely to be UUVRON 1’s primary concern regardless of whether it is considered an operational or trials unit.
If the Navy sticks to its existing plans, we should start seeing some clues about what conclusions they’ve arrived at in the next few years.

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Wednesday, October 4, 2017

After the tsunami, Japan’s sea creatures crossed an ocean


Oregon State University scientists and a team of others have discovered plastic marine debris played a key role in transporting non-native species after the March 2011 Japanese earthquake and tsunami. The findings suggest that expanded coastal urbanization and storm activity, including the recent hurricanes and floods around the world, and predicted future enhanced storm activity due to climate change, could mean that the role of marine debris as a novel vector for invasive species may be increasing dramatically.

From NYTimes by Martin Fackler

The towering tsunami that devastated Japan six years ago also unleashed a very different sort of threat onto the distant coastline of North America: a massive invasion of marine life from across the Pacific Ocean.

Hundreds of species from the coastal waters of Japan — mostly invertebrates like mussels, sea anemones and crabs — were carried across the Pacific on huge amounts of floating debris generated by the disaster, according to a study published Thursday in Science.
Less than a year and a half after the enormous earthquake and tsunami on March 11, 2011, left more than 18,000 dead or missing in Japan, the first pieces of wreckage began washing up on the shores of Canada and the United States.

To the surprise of scientists, the debris was covered with sea creatures that had survived crossings that in some cases had taken years.


Sea slugs brought to Oregon by a Japanese derelict vessel from the Iwate Prefecture.
Credit John W. Chapman

The study’s authors say it is too early to tell how many of these tiny invaders have gained a foothold in North American waters, where they could challenge or even displace native species.
While such “rafting” of animals across oceans happened in the past, the authors say the Japanese tsunami is unprecedented because of the sheer number of organisms that it sent across the world’s largest ocean.

And this points to one of the main findings of the study: that this mass migration was the result of not just the huge natural disaster, but changes in human behavior.
Such large numbers of marine animals were able to cross the Pacific because they rode on debris — made of materials like plastic and fiberglass — that proved durable enough to drift thousands of miles.

These synthetics, the use of which has taken off around the world, can stay afloat for years or even decades.
The debris that was dragged out to sea by the 2011 tsunami formed an unsinkable flotilla capable of transporting a large population of organisms across the world’s largest ocean.

Debris thought to have floated from Japan was prepared for inspection at Hatfield Marine Science Center at Oregon State University in Newport, Ore.
Credit John W. Chapman

“We have created a new ecological process, the process of mega-rafting,” said Steven L. Chown, a professor of biology at Monash University in Australia, who was not involved in the report, but wrote a commentary that also appeared in Science.
“The development of materials that can float for ages, and the rising levels of seas due to climate change, make the possibility of these events larger and larger.”

This flotsam ranged in size from coolers and motorcycle helmets to entire fishing boats and even larger objects, teeming with living sea animals that were native to the coastal waters of Japan, but foreign to North America.

John Chapman inspected a derelict vessel from Japan that had washed ashore on Long Beach, Wash. Hundreds of species from Japanese coastal waters were carried across the Pacific on floating debris generated by the 2011 tsunami.
Credit Russ Lewis

The larger the object, the more animals it carried.
One of the first pieces of tsunami debris that appeared was a 180-ton floating dock that washed ashore in Oregon in June 2012.
It was carrying a diverse mini-ecosystem of more than 120 different species.

“This was our first heads up, that this was the vanguard of what might be coming from Japan,” said one of the report’s co-authors, James T. Carlton, a professor emeritus of marine sciences at Williams College.
“After that, we got a steady stream of reports of boats, buoys and other debris, all with Japanese markings, and all carrying an amazing cross section of Japanese sea life.”

Dr. Carlton called it remarkable that such a wide range of species — which also included barnacles, worms and tiny filter-feeders called bryozoans — could survive the journey across the northern Pacific.
In many cases, these passages took years, longer than the life spans of the individual organisms.
The authors concluded that not only did these creatures adapt to an open ocean where food was scarcer than in rich coastal waters, they were also able to reproduce, in some cases for at least three generations, before reaching the North American coast.
“We found that hundreds of species could survive for multiple generations at sea,” said Dr. Carlton, who is a former director of William’s Maritime Studies Program in Mystic Seaport, Conn.
“They could do this so long as their rafts did not dissolve or sink.”


The 2011 tsunami, sweeping shores along Iwanuma in northern Japan, left more than 18,000 dead or missing, and sent an unprecedented number of organisms across the world’s largest ocean. CreditKyodo News, via Associated Press

To conduct the study, the authors relied on more than 200 volunteers, including state park rangers and beachcombers, to find and examine some 634 pieces of debris that washed ashore from 2012 to earlier this year.
While there was concern in the early days that some debris might have been contaminated from the nuclear accident at Fukushima that was caused by the tsunami, Dr. Carlton said such worries quickly eased after tests showed no traces of radioactive contamination.

The washed up objects were found to carry 289 invasive species from the western Pacific.
While most were invertebrates, a few vertebrates survived the journey, including a small number of emaciated fish that were trapped inside the water-filled hulls of half-sunken fishing boats.

Researchers tracked invertebrates and fish that traveled thousands of kilometers across the Pacific on debris such as boats, buoys, and fragments of docks.

All told, thousands of pieces of debris from Japan washed up on North American coasts from Sitka, Alaska, to Monterey, Calif., and as far afield as Hawaii.
Since the authors and volunteers were only able to inspect a fraction of these objects, Dr. Carlton said he believes hundreds more species likely made the crossing.

It is unclear how many of these will actually gain a foothold in North America.
It takes years for an invasive species to establish a viable population, and these may be hard to spot on so long a stretch of coastline.
Most of the newcomers will simply vanish in a Darwinian process of selection that Dr. Carlton likened to “a game of ecological roulette.”

Species that do prosper can cause enormous environmental and economic damage, especially if they supplant native species upon which coastal communities depend for livelihoods.
The study concluded that such disruptions will become more frequent as the use of plastics and other synthetics proliferates.
Nor does it take an event as rare as a giant tsunami to launch the next invasion fleet.
Dr. Carlton pointed to Hurricane Irma, which blew large amounts of plastic debris from devastated Caribbean islands onto Florida’s beaches.
“We have loaded the coastal zones of the world with massive amounts of plastic and materials that are not biodegradable,” he said.
“All it takes is something to push this into the ocean for the next invasion of species to happen.”

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Tuesday, October 3, 2017

Italia (Istituto Idrografico della Marina/Navimap) update in the GeoGarage platform

9 new nautical raster charts added
see GeoGarage news

 15th Century map of Italy via the New York Public Library
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Two yachts become first ever vessels to enter Central Arctic Ocean without icebreaker support

The crew of the Arctic Mission have sailed their two yachts, Bagheera and the Snow Dragon II,
to within 600 miles of the North Pole
Conor McDonnell

 From The Independant by Ian Johnston


Polar explorer Pen Hadow warns the international waters at the top of the world are 'about to be plundered by the few, very much to the detriment of the global community'

Two yachts have become the first vessels in history to sail into the Central Arctic Ocean without icebreaker support in a fresh sign of how much sea ice has been lost.

 Svalbard in the GeoGarage platform (NHS chart)

Pen Hadow, a British polar explorer, Erik de Jong, a Dutch sailor, and their crews sailed to within 600 miles of the North Pole, reaching a latitude of more than 80 degrees north.

 These explorers have already given up the attempt to reach the North Pole.
They stopped approximately 640 miles short of the north pole.

Scientists have warned that the Arctic will be almost completely free of sea ice by the late 2030s with the region experiencing greater warming than the global average.
The average winter temperature in the Arctic island of Svalbard is now about a staggering 10 degrees warmer than just a few decades ago.

  They didn't even get north of 80 degrees north.
What stopped them? Sea Ice.

Mr Hadow is the only person to have walked solo from Canada to the North Pole without resupply by third parties and has also walked to the South Pole, again without resupply.
The sea ice is so thin or has disappeared completely that it is no longer possible to walk from Canada or Russia to the North Pole.
But it is on course to become a possible sea journey.


Speaking from his yacht, the Bagheera, Mr Hadow told The Independent: “I believe sooner rather than later a yacht will sail to 90 degrees north.
“We’ve hit the buffers now, we’ve hit the main body of the sea ice, but we have been sailing in open waters quite happily.
“The Central Arctic Ocean … is officially an unexplored ocean because it’s been inaccessible to vessels until very recently.
“If we can take two 50ft yachts, image what commercial shipping and commercial fishing can now do.”
Such exploitation could pose a danger to wildlife in the region, Mr Hadow said.
“The sea ice is going – that’s one stress for them – and now there’s a very high risk of additional human threats coming in,” he said.


The Central Arctic Ocean is an area about the same size as the Mediterranean Sea that lies outside the territorial waters of the surrounding countries, which extend 200 miles from their coasts.
Mr Hadow described being able to sail into the area so easily as a "bitter-sweet moment".
“I hope this project helps to make people realise that there’s a whole resource up here which is about to be plundered by the few, very much to the detriment of the global community, unless we do something about it," he said.
“Every nation owns it, we all own it, everybody.”
He added that they planned to gather scientific information to help policymakers protect the unique habitat.

The news comes after a Russian tanker – ironically carrying a cargo of fossil fuels that are driving global warming – was able to sail from Norway to South Korea through the Arctic in just 19 days, a trip that would have taken far longer if it had travelled via the Suez Canal.
Cruise ships are also now sailing through the once famously impassable Northwest Passage along the coast of Canada.

According to the US National Snow & Ice Data Centre, the sea ice in the Arctic this year is tracking well below the average between 1981 and 2010.
The sea ice reaches its minimum extent in September before starting to grow again as the temperatures cool with the approach of winter.
In the Antarctic, the sea ice is also below average as it approaches its maximum extent towards the end of the southern winter.

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