Wednesday, May 12, 2021

China makes ‘world’s largest satellite image database’ to train AI better

The images were compiled with the help of access to China’s new Gaofen observation satellites.
Photo: Chinese Academy of Sciences

From SCMP by Stephen Chen 
 
New FAIR1M database is tens or hundreds of times larger than previous data sets, according to Chinese Academy of Sciences
Database of 15,000 high-definition images with 1 million labelled ‘scenes’ can aid AI’s accuracy, such as enabling it to identify not only a plane but its model

A satellite imaging database containing detailed information of more than a million locations has been launched in China to help reduce errors made by
artificial intelligences when identifying objects from space, the Chinese Academy of Sciences said on Wednesday.

The fine-grained object recognition in the high-resolution remote sensing imagery (FAIR1M) database is tens or even hundreds of times larger than similar data sets used in other countries, it said.

Professor Fu Kun, a lead scientist on the FAIR1M project with the academy’s Aerospace Information Research Institute in Beijing, said the relatively small size of databases for artificial intelligence (AI) training in satellite image recognition had affected accuracy in real-life applications.

Satellite images in the data set have more specific labelling than in previous ones.
Photo: Chinese Academy of Sciences
 
“A challenging and excellent data set can accelerate the development of the field,” he and colleagues said in a paper about their work, posted on arxiv.org in March.

Militaries have used spy satellites to study objects of interest since the 1960s. 
Assessment was initially done manually by trained professionals, before computers helped to speed up the process.
Military image recognition technology was mostly classified, and usually limited to a small range of sensitive objects.

In recent years, rapid development of AI technology has enabled civilians to obtain valuable information from commercial satellite images.

Counting the number of cargo trucks on the roads of a city or even a country, for instance, could provide insight into economic activity, transport and infrastructure.

Some researchers in China have used the technology to track the speed of city expansion in
Xinjiang, wild animal movements on the Tibetan Plateau and worldwide construction of infrastructure under the Belt and Road Initiative.

Existing AI algorithms have sometimes struggled to recognise objects in images taken from orbit, however.
Most civilian tools were trained using photographs taken in daily life, but an image of the Eiffel Tower taken by a tourist, for instance, would have little similarity to a shot taken from 300km (186 miles) above.

The new data set will allow AI to distinguish between types of planes or sports facilities.
Photo: Chinese Academy of Sciences

The bigger a training database, the smarter the AI becomes.
But with satellite images being relatively limited in number and sometimes quite expensive, especially those in higher definition, the accuracy of AI remained quite low in civilian applications.

With funding from the China National Science Foundation and access to the brand-new
Gaofen observation satellites, Fu and colleagues built a database containing more than 15,000 high-definition satellite images with 1 million labelled “scenes”.
The VEDAI database in France has only about 3,600 scenes.

The whole Chinese data set will be open to the international community in June, and the International Society for Photogrammetry and Remote Sensing, whose headquarters is in Germany, has chosen it as a standard database to evaluate performance of object detection algorithms, according to the society’s website.

A satellite imaging database containing detailed information of more than a million locations has been launched in China to help reduce errors made by
artificial intelligences when identifying objects from space, the Chinese Academy of Sciences said on Wednesday.

The fine-grained object recognition in the high-resolution remote sensing imagery (FAIR1M) database is tens or even hundreds of times larger than similar data sets used in other countries, it said.

Professor Fu Kun, a lead scientist on the FAIR1M project with the academy’s Aerospace Information Research Institute in Beijing, said the relatively small size of databases for artificial intelligence (AI) training in satellite image recognition had affected accuracy in real-life applications.

Satellite images in the data set have more specific labelling than in previous ones. Photo: Chinese Academy of Sciences
 
“A challenging and excellent data set can accelerate the development of the field,” he and colleagues said in a paper about their work, posted on arxiv.org in March.

Militaries have used spy satellites to study objects of interest since the 1960s. Assessment was initially done manually by trained professionals, before computers helped to speed up the process.
Military image recognition technology was mostly classified, and usually limited to a small range of sensitive objects.

In recent years, rapid development of AI technology has enabled civilians to obtain valuable information from commercial satellite images.

Counting the number of cargo trucks on the roads of a city or even a country, for instance, could provide insight into economic activity, transport and infrastructure.

Some researchers in China have used the technology to track the speed of city expansion in
Xinjiang, wild animal movements on the Tibetan Plateau and worldwide construction of infrastructure under the Belt and Road Initiative.

Existing AI algorithms have sometimes struggled to recognise objects in images taken from orbit, however. Most civilian tools were trained using photographs taken in daily life, but an image of the Eiffel Tower taken by a tourist, for instance, would have little similarity to a shot taken from 300km (186 miles) above.
 
The new data set will allow AI to distinguish between types of planes or sports facilities.
Photo: Chinese Academy of Sciences
 
The bigger a training database, the smarter the AI becomes.
But with satellite images being relatively limited in number and sometimes quite expensive, especially those in higher definition, the accuracy of AI remained quite low in civilian applications.

With funding from the China National Science Foundation and access to the brand-new
Gaofen observation satellites, Fu and colleagues built a database containing more than 15,000 high-definition satellite images with 1 million labelled “scenes”.
The VEDAI database in France has only about 3,600 scenes.

The whole Chinese data set will be open to the international community in June, and the International Society for Photogrammetry and Remote Sensing, whose headquarters is in Germany, has chosen it as a standard database to evaluate performance of object detection algorithms, according to the society’s website.

FAIR1M provides more information on images.
Other databases, for example, have described passenger planes as simply planes.
The new Chinese database could teach the AI a plane’s exact model, such as Boeing 777, or challenge it to distinguish a warship from a passenger ship.

“Building a large database is quite challenging,” said Xia Guisong, professor of remote sensing at Wuhan University, who was not involved in the FAIR1M project. “Objects need to be verified and properly labelled by hand.”

FAIR1M is not the only large-scale satellite image object database for AI in China. 
The DOTA database developed by Xia’s team also contained a million scenes, but using fewer satellite images and labels. Xia said DOTA and FAIR1M were not competing with each other.

“We focused on objects viewed by satellites from different angles; they focused more on details in high resolution,” he said. 
“These two data sets address different technical challenges. They complement one another.”

Military target recognition technology is believed to perform better than civilian counterparts, but the latter is catching up thanks to quickly evolving AI technology and improved training data.

“The algorithms that we develop work at fundamental levels,” Xia said, meaning they can be used in military or civilian settings.
 

Development of AI image recognition technology in China previously depended mostly on databases from other countries.
Now, with two of the world’s largest satellite image databases, China has a greater chance of gaining or maintaining a lead in the field.

“The database is a platform. On this platform any research team from any country can develop different algorithms to beat one another, according to certain rules,” Xia said.
“This will accelerate the pace of technology development as a whole.”

In the past, satellite images were collected mostly by Western countries.
Recently, China has built up one of the largest Earth observation networks with satellites such as the Gaofen series that were equipped with cutting-edge cameras and sensors.

More than 80 per cent of the images in the FAIR1M database came from the Chinese satellites, and the rest from Google Earth, according to Fu’s team.
They contained vehicles, machinery such as excavators, and constructions including bridges, roundabouts and baseball fields.

In May, AI researchers from many countries will compete in Beijing for a trophy awarded for satellite image recognition technology, using the FAIR1M database, the academy said.

The competition would “drive the development and application of China’s high-definition satellite image data and technology in international society”, it said.
 
Links :

Tuesday, May 11, 2021

Spain (IHM) layer update in the GeoGarage platform

6 rasterized ENCs added 

China’s fishing fleet, the world’s largest, drives Beijing’s global ambitions

Recent satellite imagery shows Chinese vessels anchored at a disputed South China Sea reef.
 Photo : Satellite image 2021 Maxar Technologies

From WSJ by Chuin-Wei Yap

Governments and conservation groups accuse the ships of fishing illegally and advancing military goals

In Beijing’s push to become a maritime superpower, China’s fishing fleet has grown to become the world’s largest by far—and it has turned more aggressive, provoking tensions around the globe.

The fleet brings in millions of tons of seafood a year to feed the country’s booming middle class. Foreign governments, fishermen and conservation groups have accused the fleet of illegal fishing, including by using banned equipment and venturing into other countries’ territory. 
That fishing has upended local economies and threatens ecosystems including around the Galápagos Islands, affected governments and fishermen say.

The Chinese fleet is helping the country stake out a bigger presence at sea, including by building a world-wide network of ports.
The vessels, rigged with winches and booms and pulling giant nets, can be twice as large as a naval patrol boat, at an average of almost 200 feet long.
Fishing crews have helped establish island settlements in waters subject to territorial disputes with neighbors.

An analysis of transponder and global vessel registration data indicates Chinese boats involved in distant-water operations—meaning outside a country’s own territorial waters—total as many as 17,000, according to London-based researcher Overseas Development Institute.
Official data and analyst estimates indicate China’s closest competitors in the industry, Taiwan and South Korea, have some 2,500 such vessels combined.

China’s foreign ministry said that legally registered vessels were far lower, at 2,701 as of 2019. China agreed to cap its fishing vessels at 3,000 in 2017, in response to World Trade Organization efforts to cut government subsidies that contribute to overfishing.

The ministry said that Beijing implements the world’s strictest oversight on distant-water fishing. It has toughened legal penalties on errant fishing in recent years.

Ecuador and Peru placed their navies on alert last year to track hundreds of Chinese trawlers massing near South American fisheries.
In Asia, governments and the fishing industry have complained of hundreds of Chinese incursions in their domestic waters. Indonesia has taken to periodically detonating seized Chinese trawlers in hopes it will deter other Chinese boats from poaching in its waters.

CHINA
EAST CHINA SEA
The sea near China is already one of the most crowded fishing areas in the world, pushing the country's distant-water fleet further away.
SOUTH CHINA SEA
The U.S. has signaled rising concern over the alliance of China's military and its fishing fleet, which has helped set up island settlements in the area.

GHANA
Fishermen in Ghana say dozens of Chinese trawlers have come into Ghana's own waters, targeting shallow-dwelling fish. China's foreign ministry said its fleet must comply with local laws.

SAMOA
In May, Indonesian authorities began investigating a Chinese tuna trawler where four Indonesian fishermen died on the high seas off Samoa, including allegations of illegal fishing. Beijing said it was looking into the case.

GALÁPAGOS ISLANDS
In August, hundreds of Chinese trawlers gathered near Ecuador's Galápagos Islands. Beijing said in response to concerns from Ecuadorian authorities that it requires its fishers abroad to comply with local laws.

From 2010 to 2019, Chinese-flagged or owned vessels accounted for 21% of global fishing offenses logged by Spyglass, a Vancouver-based fishing crime database, up from 16% the previous decade.
A 2019 global ranking by Geneva-based Global Initiative, a transnational crime watchdog, placed China first in the prevalence of illegal fishing by nations.

In the West African nation of Ghana, fishermen say that dozens of Chinese trawlers, equipped to fish at all depths, are venturing daily from their deep-sea license remits into Ghana’s sovereign waters, targeting shallow-dwelling fish that used to be a local preserve.

“Because the trawlers have depleted our fish stocks at a very fast rate, we all owe debts, and it has made our life extremely difficult,” said Kojo Panyin, a 53-year-old fisherman in Axim, a Ghanaian fishing village.
Such fishing also destroys the nets of local fisherman, he said.

China’s foreign ministry said it requires its fishers abroad to comply with local laws.

For China, the industry feeds a rapidly growing middle class and creates tens of millions of jobs in fishing, aquaculture and seafood processing.
It also reflects China’s growing assertiveness. Distant-water fishing is enshrined in Xi Jinping’s national development blueprint and is a key part of his Belt and Road global infrastructure plan, which includes ocean routes.
“The industry is important for ensuring national food security,” the blueprint says. 
“It is of great significance in safeguarding national maritime rights and interests.”

A Chinese fishing boat, which was tested in 2020, has a maximum range of 5,000 nautical miles,
74 beds and 49 fishing spots.
Photo : Huxuejun / SIPA Asia / Zuma Press

Mr. Xi’s plan called for the world-wide development of 29 distant-water fishing bases, which help to project Beijing’s vision of itself at the center of a web of global infrastructure.

In West Africa, Fuzhou Hongdong Pelagic Fishery Co. is using $60 million in state funds to expand a fishing port in Mauritania, China’s largest distant-water base, state media reports say. China has no naval base in the region.

Chinese companies also are building a fishing port in Pakistan, near a major oil route and where Beijing jockeys for geopolitical influence.

First fleet
 
China’s first distant-water fleet, launched in March 1985, comprised 13 fishing boats cobbled together from ships and personnel lent by freight companies, state records show.
Beijing hoped that the state-owned flotilla, financed with a few hundred thousand U.S. dollars, according to records, would spur China’s engagement with the global economy.

Making Waves
China's demand for seafood has soared over the decades
Sources: Wind (imports); The Stimson Center

In its first full year of operation, the fleet harvested some 20,000 metric tons of seafood, official data show. At first, the country sold almost all of its distant-water catch abroad.
Now the fleet sends two-thirds of its harvest home to China, according to state data.

Since 2015, China’s distant-water catch has averaged two million tons a year, according to state data, which analysts say could undercount the actual total.

The nation now is the world’s largest seafood consumer and in 2019 was the third-largest seafood importer, after Europe and the U.S. Seafood imports to China totaled $15 billion in 2019, double the figure from four years earlier. Ecuador, the world’s largest shrimp exporter, sells twice the volume of shrimp to China as it does to the U.S., France and Spain combined.

While three-quarters of the fishing fleet is now privately owned, the Chinese state maintains a large presence in the industry.
The nation’s largest distant-water firms, China National Fisheries Corp., a unit of an agricultural conglomerate directly managed by the central government, and its subsidiaries, remain state-owned.

Closely held operators keep close ties with the government, rely on state subsidies and often have state investors. The chairman of Fuzhou Hongdong, which is building the port in Mauritania, is a delegate to China’s legislature.
The companies didn’t respond to requests for comment.

The industry helps China act on territorial claims, such as by sending fishermen to set up settlements on previously unoccupied atolls in the South China Sea.
In turn, the state regularly defends fishing interests.

The Chinese navy, coast guard and paramilitary often join hundreds of fishermen in motorboats in regional seas where China has built artificial islands with military-capable facilities, including air strips, jet fighter hangars and naval bases.

Vietnamese officials say a Chinese coast guard ship sank a Vietnamese fishing boat in April near the Paracel Islands, which both nations claim. Beijing said the Vietnamese vessel collided with the Chinese.

The incident followed Chinese altercations with fishing vessels from other South China Sea claimants such as the Philippines and Indonesia over the years. 
 
‘Rule-breaking’

Maritime law allows coastal states varying levels of control over seas up to 200 nautical miles from their shoreline.
Most states seek to restrict foreign operations in their territorial waters, including fishing.

In October, Malaysia’s maritime authorities detained six Chinese fishing vessels, accusing them of trespassing in its waters.

In August, some 300 Chinese trawlers fished near Ecuador’s Galápagos Islands.
Ecuador said it was the largest gathering of such Chinese vessels, and accused them of using illegal means to evade being identified, such as turning off tracking systems and altering their names.

A large Chinese fishing boat pictured during an overflight by the Ecuadorean Navy patrolling waters around the Galápagos Islands.
Photo : Marcos Pin / EFE / Zuma Press

Ecuadorean defense officials held an August 2020 news conference
about the presence of the Chinese fishing fleet.
Photo : Segundo Mendez, Reuters
 
Ecuadorean officials said Chinese fishing threatened the biodiversity of the Galápagos, where some animals depend on the squid that the Chinese vessels were netting.
China’s foreign ministry has said Beijing would halt the fleet’s fishing there from September to November.
“Over the past five years, there has been a giant transformational shift with the Chinese distant-water fleet,” said Steve Trent, co-founder of London-based conservation group Environmental Justice Foundation. 
“They are devastating the small [open water] fisheries, the fish that coastal communities depend on for their livelihoods.”

Ghana reserves an area six nautical miles from shore for local fisheries. Chinese trawlers increasingly ignore these poorly policed rules, fishermen and conservation groups say.

The modern Chinese industrial trawler can fish 700 tons a day, a volume that would take the largest African fishing canoe six months to harvest, industry data show.
Residents of Axim, which largely relies on fishing for income, now have to drive to another town 80 miles east to buy the catch from the Chinese, said Mr. Panyin, the fisherman.
 
Many Ghanaian communities depend entirely on fishing for income.
Photo : EJF Environmental Justice Foundation

Chinese trawlers typically operate under the Ghanaian flag.
Photo : EJF Environmental Justice Foundation
 
Ghana’s marine police in June detained the Chinese-owned trawler Lurongyuanyu 956, accusing its operators of using illegally-sized nets. 
“You see this vessel through global fishing logs, going back and forth from coastal waters to Ghana,” said Dyhia Belhabib, Spyglass’ developer and principal investigator for conservation group Ecotrust Canada.

China’s foreign ministry said it had taken note of the allegations. 
State records show the vessel is owned by eastern China-based Rongcheng Marine Fishery Co. Staff there declined to make anyone available for comment.

Fishing communities often are overshadowed by larger priorities in bilateral trade. 
Ghana’s fishing output last year of around $480 million is a fraction of its $7.3 billion annual trade with China, which includes oil and metals. Beijing funds big Ghanaian projects from dams to theaters.

How should governments monitor fishing by other countries?

In neighboring Sierra Leone, where China has invested billions of dollars to develop mining and highways, local authorities say that illegal Chinese fishing drains $29 million annually in state revenue—but that they are ill-equipped to police it.
In August, Sierra Leone’s fisheries ministry said it had lost track of three Chinese-owned trawlers that fled after being charged by police a month earlier with illegally fishing within Sierra Leone’s territorial waters.

Even on the high seas, which are relatively free from the scrutiny of sovereign authorities, Chinese trawlers have come under investigation.

In May, Indonesian authorities began probing a Chinese tuna trawler where four Indonesian fishermen died while on the South Pacific Ocean.
Beijing said it was looking into the case. Indonesian fishermen working aboard say that they were made to harvest shark fins, a popular delicacy in China, in breach of regionally-agreed rules on fishery management.
“From October, we stopped catching tuna,” said fisherman Rizky Alvian. 
“Every day, we catch shark. Just shark.”
 
A Chinese fishing vessel in the Whitsun Reef located in the disputed South China Sea.
Photo : Satellite image 2021 Maxar Technologies
 
Links : 

Monday, May 10, 2021

Why the sailing yacht movement is greener than ever

From Boat International by Marilyn Mower
 
There are few more eco-friendly ways to travel than by sailing yacht, but, thanks to fresh innovations, the future is ever greener.
 
If you want to go around the world, the only way to do it with any conscience is on a sailing boat,” asserts Wally Yachts CEO Luca Bassani.
Indeed, environmental sensitivity and mounting scientific and social pressure for reducing fossil-fuel consumption seemed to be making progress until Covid-19 took over the news cycle.
Interestingly, naval architects, designers yacht builders and suppliers have continued nose to the grindstone in anticipation of a future that is not a bounce back but a bounce forward toward a day when far more yachts are powered by sail, and those yachts make an ever smaller environmental impact.

Rather than a green revolution, the actual picture is incremental, “a steady drip, drip, drip,” as naval architect Bill Tripp puts it. 
“Progress is an S-shaped curve slowly moving up but then something comes along and the axis shifts and it steepens quickly. That’s what happened with electric cars. It was a very long, low curve, but now you can argue that one of the best cars in the world is electric.”

The Wally 145 has a hybrid propulsion system
Credit: Wally

Is the totally electric boat a possibility?
Definitely for a small boat or yachts that primarily day sail, says Tripp, but a superyacht with its high hotel load is a different matter with a lot of variables.
Let’s take a look at the puzzle pieces emerging for the development of low-to-no impact superyachts.

A good sailing boat is an efficient boat, but “efficient” can mean either faster or less costly to operate, both attractive outcomes but for different reasons and perhaps to different customers.

At yacht builder Southern Wind, the mantra is “Improving sustainability through efficiency.” 
Taking weight out is an everyday battle but the yard attracts customers who like the large but pared-down ethos of its boats and their modest crew requirements.

Credit: Southern Wind Yachts

“One of the complaints about sailing boats during Med cruising season is that the wind is too light and the boat won’t go anywhere in less than six to eight knots of breeze unless it’s motoring. We put our effort into resolving that issue,” says Southern Wind commercial director Andrea Micheli. 
“If a boat has a bigger sailplan, it can sail faster and at a lower wind speed. Our new 105 will carry 15 per cent more sail area than our 102-footer [31-metre]. It will sail in four knots true wind! We will go upwind at 4.5 knots and downwind at 4.9 knots. At seven to eight knots of wind, we sail beautifully at eight to nine knots while most of our competitors will be motoring.”

Of course, sail area is not the only string to the yard’s bow.
Boats consume remarkably little energy when sailing; it is the time at anchor with owners and guests aboard when the hotel loads explode.
Even a blue-water cruiser sits for about eight months of the year. Southern Wind has invested in the development of awnings that can generate seven to 20kW of electricity using solar cloth panels that stow in a dedicated deck locker.

Credit: Bill Dixon Yacht Design

“When the owner and guests are gone, we think the boat can be nearly energy self-sufficient when on a mooring or at a dock,” says Micheli. 
“It also keeps the boats cooler during the day. You won’t need to supplement as much with a generator or shore power.”

“This summer we delivered Kauris IV, which has huge battery banks,” says Bassani. 
“You can motor at 10 knots for eight hours if you don’t have wind. Unfortunately, available solar cells for recharging a yacht of this size are not enough. You can keep a stationary 40-footer [12-metre] charged on solar, but not a superyacht.”

Efficiency also means power management systems and using battery power for peak shaving (upsizing battery banks to draw power off them for silent running or short-term loads) instead of upsizing gensets. 
“Based on our real data, the 105 will have two 19kW gensets,” says Micheli. One can power the boat and charge the batteries while the other manages short-term demands or hydraulics for sail hoists. Small gensets will run at 70 to 80 per cent load, which is much better for them. Proprietary software lets crew manage energy generation and use.”

The heights of hybrid

Royal Huisman, which pioneered hybrid power with Ethereal in 2009, has an ongoing complete hybrid re-power of its 43.5-metre Juliet to give it the ability to cruise zero-emissions zones.
The centrepiece is a new gearbox aligned with a sophisticated electric motor/generator for indirect electric propulsion from the battery bank for silent operation, or a generator via the power management system.
The main engine can still turn the prop shaft if necessary or provide electric power to meet the hotel load.

Naval architect Merfyn Owen says that on 25- to 35-metre yachts the main power consumers are air conditioning and refrigeration. 
“Adding insulation and scaling back expectations need to be part of the package, but the right combination would be peak shaving. Entering and exiting a harbour at low speed is not good for an engine; it’s better to use electric motors when you only need six knots.”
He has a 25-metre high-latitudes yacht in construction that will enjoy hybrid propulsion.

Credit: Royal Huisman

“We find peak shaving very effective in that crew don’t need to start up another generator for a short period of extra load that can be handled by the batteries,” says Royal Huisman project manager Henriko Kalter.
“Project 404, a 59.7-metre sloop, will be fully diesel-electric, meaning [there will be] no main engines but a system that pulls power for all uses off a grid fed by several smaller generators.
These are just for recharging and can be smaller than mains.

“Let’s say your peak load when everything is on is 100kW, but the rest of the day it drops to around 25kW. It’s not good for a 100kW generator to be running at 25 per cent load – the maintenance is awful. So if we put in a 50kW generator, we charge the batteries when power consumption drops below 50 kW and draw from the batteries when it goes above. It also allows us to use a more basic DC system for everything, which gives us more options, such as two retractable electric drive legs.


“Our ‘smart energy’ approach has two pillars – one to reduce power consumption and one to generate electrical power,” continues Kalter. 
“We studied where power is consumed on the boats and it’s primarily the galley and air conditioning, which take 50 per cent of the power. Beyond waste heat recovery, we are also recovering cool air. Ventilation systems just dump cooled air over the side but we are using the previously cooled air to pre-cool the fresh air coming in so the ambient temperature is being reduced in two steps.

“We are also looking at hydrogen and we have been talking to Lloyd’s about storage safety,” says Kalter.
 “The problem is availability. Can you go from Antigua to the Med on hydrogen? Probably not. We look to solar and hydro-generators when the boat is under way, [so] it’s not one solution but many contributors to becoming autonomous. We think a totally fossil-free boat is possible.”

Sunreef Yachts’ Eco 80 is covered in solar cells powering enough battery capacity to allow silent mode all night long
Credit: Sunreef

Catamaran builder Sunreef Yachts introduced its Eco line with an 18-metre at Cannes 2019.
Now it has scaled up to a 24-metre that will be available in both power and sailing versions. 
“Electric power is the basis but we take it further,” says Sunreef Yachts’ Artur Poloczanski. 
“The boats are designed with enough battery capacity to allow silent mode at night, and we use a non-toxic silicon bottom paint that is slicker than most paint, so there is less resistance. We have also used reclaimed teak for the soles inside the boats, and having water makers with purification means you don’t need to lug around plastic bottles.”

A recent source of pride is the yard’s design of integrated carbon-fibre bimini tops that take advantage of new high-output solar cells that can be curved – both saving weight and improving aesthetics. 
The E series boats use these same solar cells in curved sections of hulls and decks. 
“We believe that 32kW peak generation from solar is achievable. Wind and hydrogeneration add more self-sufficiency,” says Poloczanski.
“Eco design and construction is a main focus for Sunreef now.” Sunreef’s own R&D has led to counter surfaces being made of compressed paper and resin, and components made of flax and basalt fibre, rather than fibreglass.

Tripp has several parallel hybrid projects under construction of sizes varying from 13 to 27 metres. 
“It’s the Prius model of batteries and an engine. 
Even if you had the 80kW of a Tesla battery pack you could only power your boat for about two and a half hours at full power – there’s not much excitement to that. 
You need a source to power the batteries.

Credit: Tom van Oossanen

“Hybrid systems are trickling up from simple systems on small boats and trickling down from huge ships,” says Tripp. 
“We found a flywheel alternator that looks like a six-inch pancake that fits between the gearbox and the engine. Under sail [with the propeller set in reverse] you lose maybe half a knot. When more systems are available, there will be more acceptance.

“Hydrogenerators with even a small propeller on a standard shaft can generate about 10kW, which makes them quite practical for small boats,” continues Tripp. 
“But superyachts have a different problem because of their greater loads and the number of people aboard. I’m always running into captains who says they have to keep the boat closed down to preserve the fabrics and woods inside. That’s a choice. I think we need to be less precious and design boats to be able to open hatches.”

“You absolutely can regenerate enough energy to cover the hotel loads on a sailing superyacht,” says naval architect Bill Dixon. 
“Black Pearl has proven that it’s possible under way with hydrogeneration and solar cells charging battery banks.”


Dixon, a proponent of the Dynarig, is developing concepts that marry the spaces associated with a motor-yacht lifestyle with the green credentials of a sailing yacht. We have enquiries from people now, mostly younger owners, who are putting their companies through sustainability analysis and realise their yacht should meet the same standards.”
 
Reduce, reuse, recycle

Naval architect Rob Doyle says he’s been “stripping away stuff” from his designs. 
“I’m always asking, ‘Do you really need that?’
It turns out owners like natural ventilation and a boat that can be silent for 15 hours.

“Boats got heavier because yards got worried about warranty issues and redundancy [so they] upsized and duplicated gear, adding cost. The lighter we make them, the cheaper it gets. Carbon fibre costs nearly twice the price of aluminium, which is totally recyclable and the hull will be close on weight. It’s often the stuff inside that’s heavy.”

Take the new ClubSwan 80 for example. Currently under construction at Persico Marine, Nautor's Swan's latest addition to its series of performance sailing yachts recycles carbon-fibre from previous moulds by separating the carbon from the resin to create new moulds.
Persico also collects prepreg scraps and ship to a company specialising in medical prostheses.


YYachts, a company based on the concept of light, efficient, uncomplicated boats, plans to show its new 21-metre Y7 Cin Cin at the Cannes show.
Its deck is laid with sustainable engineered wood from Lignia that looks like teak, weighs the same and mellows to the same silver grey.

YYachts also internalises environmental protection.
Founder Michael Schmidt insists that subcontractors come from within a 100-kilometre radius to lower transportation costs and reduce the carbon footprint. 
“We digitalised the shipyard as much as possible to reduce travelling and installed LED lighting everywhere. In addition, we use second-hand shipping containers as office space and let a couple of sheep take care of the grass in front of the yard,” he says. 
“We are also focusing on new materials we can use on our projects, such as green resin foam generated from recycled PET bottles.”


“If a customer’s company has to meet zero-carbon status by 2030, then their personal possessions probably also should,” says Kalter. 
“We are seeing more owners moving in this direction in tender packages we receive, some even coming from motor-yacht owners. It’s not that they want to do regattas, but they don’t want to give up the yachting lifestyle.”

Voicing cautious optimism, Tripp adds, “We’ll see all these things come to the fore, hopefully driven by clients demanding it rather than by naval architects saying you could have it.”

Sunday, May 9, 2021

The swim, official trailer

 
In 2018, Seeker chronicled Ben Lecomte’s historic swim across the Pacific to raise awareness for the state of our oceans.
Now, Lecomte’s incredible expedition has been turned into a full-length documentary, streaming now on Discovery+. Terms apply.
Watch here: http://bit.ly/dplus-yt​ »
Watch more Swim | http://bit.ly/TheSwimPlaylist
 
He swam from Japan to Hawaii and at times saw a piece of plastic in the ocean every three minutes https://www.cnn.com/2018/12/11/us/pac...​ 
"A French man’s attempt to swim across the Pacific Ocean may be over for now, but his campaign to warn the world about the dangers of plastic pollution in the ocean continues." 
Six months. 5,700 miles. 
One ocean. 
 
Ben Lecomte wants to be first to swim across Pacific.
"Ben Lecomte, a 50-year old Frenchman turned Texan, will slip into the water on Sunday off the coast of Choshi, Japan, and start swimming. 
If all goes as planned, he won’t set foot on land for six months. In that time, he plans to swim through the largest collection of trash on the planet, great white shark migration areas, through jellyfish and storms and isolation and monotony." 
 
Man begins to swim across Pacific Ocean, garbage patch and all https://www.nbcnews.com/news/world/ma...​ 
"Lecomte said he is undertaking the expedition as a kind of existential challenge and to help publicize threats like the Great Pacific Garbage Patch — the vast expanse of man-made pollution that fouls that ocean."
 
Ben Lecomte's historic swim across the Pacific Ocean is a feat that can’t be missed.
Join us as we dive into the most extensive data set of the Pacific Ocean ever collected.
Learn about the technology the Seeker crew is using to deter sharks away from Ben and measure the impact of the long-distance swim on his mind and body.
Ben's core mission is to raise awareness for ocean health issues, so we’ll investigate key topics such as pollution and plastics as he swims closer to the Great Pacific Garbage Patch, discover potential consequences from climate change, and examine how factors like ocean currents can impact his progress along the way.
Seeker empowers the curious to understand the science shaping our world.
We tell award-winning stories about the natural forces and groundbreaking innovations that impact our lives, our planet, and our universe. 
 
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Saturday, May 8, 2021

Reynisfjara black sand beach, the most famous beach on the South Coast of Iceland


Reynisfjara is the most famous beach on the South Coast of Iceland.
 
Localization with the GeoGarage platform (Icelandic nautical raster chart)
 
Its beautiful black sand, powerful waves, and the nearby Reynisdrangar sea stacks make Reynisfjara a truly unique place to visit and a popular filming location (Game of Thrones, Star Wars and more).
Reynisfjara Beach is one of the most well-known black sanded beach in the whole world.
This is a place of wild and dramatic beauty where the roaring waves of the Atlantic Ocean power ashore with tremendous force.
 
In 1991, Reynisfjara appeared on the top ten list of the most beautiful non-tropical beaches in the world, and it is very easy to see why it was chosen!
It is said that to stand on Reynisfjara Beach is akin to being in a natural amphitheater where the white water of the Atlantic waves provides the drama.
At any time of year, and in any light, this is a place of great beauty which will remind people that they can never be far from the powerful forces of nature which shaped the island of Iceland.
Marvel at the power of the ocean but do not stand too close – those masterful waves deserve your respect and can be quite dangerous if you get too close! 

Friday, May 7, 2021

This map is alive with the beauty of lighthouse signals

At night, the rims of the North Sea flicker and flash with a multitude of light signals to guide ships to safety.
Credit: Geodienst – Lights at Sea


From BigThink by Frank Jacobs

The unique light signatures of nautical beacons translate into hypnotic cartography.
  • Many of the world's 23,000 lighthouses feature a distinct combination of color, frequency, and range.
  • These unique light signatures help ships verify their positions and safeguard maritime traffic.
  • But they also translate into this map, visualizing the ingenuity and courage of lighthouse builders and keepers.
Land and sea are both shaded dark, so it's a bit hard at first to make out that this collection of merrily blinking lights is actually a map.
Once the coastal contours pop, though, all becomes clear: these are lighthouses!


At night, the Eastern Mediterranean is awash with lighthouse signals.
Credit: Geodienst – Lights at Sea

The Age of Big Data

The map not only shows where they are, but how they are: static or blinking in various colors with the size of the circles corresponding to the range of their lights.

Up until the 20th century, a map of lighthouses would have been a subdued affair: just a string of dots strung along lines of coast. But this is the 21st century!
We're in the Age of Big Data, ruled by the clever boffins who know how to stitch one dataset to another. Zap it with electricity and presto: it's alive!

That's what the folks did over at Geodienst, the spatial expertise center of the University of Groningen (Netherlands). Back in 2018, student/assistant Jelmer van der Linde (currently with the University of Edinburgh) came across OpenSeaMap, an open-source resource for nautical information similar to its more famous landlubber cousin, OpenStreetMap.

OpenSeaMap contained a database with detailed information on nautical beacons and lighthouses, which included not just their location, but also the frequency, range, and even the color of their signals. Would it be possible to visualize all those data points on a map?
Yes, it would!


Norway's craggy coastline requires lots of light.
Not that much blinking going on, though.
Credit: Geodienst – Lights at Sea

The result is this riot of a map. It's important that ships don't mistake one lighthouse for another.
That's why they come in various colors and their lights flicker with a distinct frequency.
Norway in particular is lit up with beacons and lighthouses, as its fjord-indented coast warrants. And the rest of Europe is well provided with nautical warning lights.

However, while the map is reminiscent of other global traffic trackers for flights (like Flightradar24 or FlightAware) or shipping (such as VesselFinder or MarineTraffic), it is neither live nor global.
The flickering lights aren't a real-time report; they merely repeat the code in the original database. And that database is incomplete.

Zoom out, and the map gets a bit too dark.
According to the Lighthouse Directory, there are at least 23,000 lighthouses in the world.
And even though the United States has more lighthouses than any other nation700 by some counts – the map only shows a handful of lights in North America.

Like its parent, the lighthouse map is open source too, so if anyone out there is capable of filling in the gaps, they can.
Lighthouse enthusiasts, get to it!

Not one yet yourself?
Below are 10 lighthouse facts to help you come over to the light side.

Now you see them, now you don't.
Credit: Geodienst – Lights at Sea

Trapped in a giant phallus and other true facts about lighthouses

  1. The world's smallest lighthouse is the North Queensferry Light Tower, near the Forth Bridge in Scotland. A mere 16 feet (5 m) tall, it was built in 1817 by Robert Stevenson, famous builder of lighthouses, as was his son Thomas, who was the father of the famous novelist Robert Louis Stevenson.
  2. Reaching a height of 436 ft (133 m), Jeddah Light in Saudi Arabia is the world's tallest lighthouse.
  3. The 2019 movie The Lighthouse, starring Willem Dafoe and Robert Pattinson, was based on a true incident, known as the Smalls Lighthouse Tragedy. In 1801, a storm trapped two Welsh lighthouse keepers, both named Thomas, in their lighthouse. One died, the other went mad. Asked to summarize his film, writer/director Robert Eggers said, "Nothing good can happen when two men are trapped alone in a giant phallus."
  4. From its inauguration in 1886 until 1901, the Statue of Liberty also served as a lighthouse. Its nine electric arc lamps, located in the torch, could be seen 24 miles out to sea.
  5. All U.S. lighthouses are now automated – save for Boston Light, the oldest continually used lighthouse in the country. For historical reasons, Congress has decided it shall remain staffed year-round.
  6. Hook Lighthouse, on Hook Head in Ireland's County Wexford, claims to be the world's oldest lighthouse still in use. It was first built by a medieval lord in the early decades of the 13th century.
  7. The Tower of Hercules in La Coruña, Spain has a slightly better claim. It was built by the Romans in the 1st century AD and still functions as a lighthouse.
  8. Stannard Rock Lighthouse is also known as "the loneliest place in the world." It is located in Lake Superior, Michigan. At 24 miles (39 km) from shore, it is the most remote lighthouse in the U.S. and one of the most remote in the world. It opened in 1883 and was staffed for parts of the year until 1962.
  9. A lighthouse on Märket is the reason for the weird border on the island, divided between Sweden and Finland. In 1885, the Finns built a lighthouse on the highest part of the island – on the Swedish half. Thanks to a complicated land swap, the lighthouse is back on the Finnish side.
  10. In the United States, August 7 is National Lighthouse Day.
Robert Pattinson (left) and Willem Dafoe in The Lighthouse.  
Credit: © 2019 A24 Films, via IMDB

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Thursday, May 6, 2021

Revealed: 2,000 refugee deaths linked to illegal EU pushbacks


Migrant rescue patrol in the Aegean Sea by the Turkish coastguard.
A case has been filed against the Greek state that claims patrol boats towed migrants back to Turkish waters and abandoned them.
Photograph: Erdem Şahin/EPA

From The Guardian by Lorenzo Tondo

A Guardian analysis finds EU countries used brutal tactics to stop nearly 40,000 asylum seekers crossing borders


EU member states have used illegal operations to push back at least 40,000 asylum seekers from Europe’s borders during the pandemic, linked to the death of more than 2,000 people, the Guardian can reveal.

In one of the biggest mass expulsions in decades, European countries, supported by EU’s border agency Frontex, systematically pushed back refugees, including children fleeing from wars, in their thousands, using illegal tactics ranging from assault to brutality during detention or transportation.

The Guardian’s analysis is based on reports released by UN agencies, combined with a database of incidents collected by non-governmental organisations.
According to charities, with the onset of Covid-19, the regularity and brutality of pushback practices has grown.

The findings come as the EU’s anti-fraud watchdog, Olaf, has launched an investigation into Frontex over allegations of harassment, misconduct and unlawful operations aimed at stopping asylum seekers from reaching EU shores.

According to the International Organization for Migration, in 2020 almost 100,000 immigrants arrived in Europe by sea and by land compared with nearly 130,000 in 2019 and 190,000 in 2017.

Since January 2020, despite the drop in numbers, Italy, Malta, Greece, Croatia and Spain have accelerated their hardline migration agenda.
Since the introduction of partial or complete border closures to halt the outbreak of coronavirus, these countries have paid non-EU states and enlisted private vessels to intercept boats in distress at sea and push back passengers into detention centres.
There have been repeated reports of people being beaten, robbed, stripped naked at frontiers or left at sea.

In 2020 Croatia, whose police patrol the EU’s longest external border, have intensified systemic violence and pushbacks of migrants to Bosnia.
The Danish Refugee Council (DRC) recorded nearly 18,000 migrants pushed back by Croatia since the start of the pandemic.
Over the last year and a half, the Guardian has collected testimonies of migrants who have allegedly been whipped, robbed, sexually abused and stripped naked by members of the Croatian police.
Some migrants said they were spray-painted with red crosses on their heads by officers who said the treatment was the “cure against coronavirus”.

According to an annual report released on Tuesday, the Border Violence Monitoring Network (BVMN), a coalition of 13 NGOs documenting illegal pushbacks in the western Balkans, abuse and disproportionate force was present in nearly 90% of testimonies in 2020 collected from Croatia, a 10% increase on 2019.

In April, the Guardian revealed how a woman from Afghanistan was allegedly sexually abused and held at knifepoint by a Croatian border police officer during a search of migrants on the border with Bosnia.

“Despite the European Commission’s engagement with Croatian authorities in recent months, we have seen virtually no progress, neither on investigations of the actual reports, nor on the development of independent border monitoring mechanisms,” said Nicola Bay, DRC country director for Bosnia.
“Every single pushback represents a violation of international and EU law – whether it involves violence or not.”

Since January 2020, Greece has pushed back about 6,230 asylum seekers from its shores, according to data from BVMN. The report stated that in 89% of the pushbacks, “BVMN has observed the disproportionate and excessive use of force.
This alarming number shows that the use of force in an abusive, and therefore illicit, way has become a normality […]

“Extremely cruel examples of police violence documented in 2020 included prolonged excessive beatings (often on naked bodies), water immersion, the physical abuse of women and children, the use of metal rods to inflict injury.”

In testimonies, people described how their hands were tied to the bars of cells and helmets put on their heads before beatings to avoid visible bruising.

A lawsuit filed against the Greek state in April at the European court of human rights accused Athens of abandoning dozens of migrants in life rafts at sea, after some had been beaten.
The case claims that Greek patrol boats towed migrants back to Turkish waters and abandoned them at sea without food, water, lifejackets or any means to call for help.

BVMN said: “Whether it be using the Covid-19 pandemic and the national lockdown to serve as a cover for pushbacks, fashioning open-air prisons, or preventing boats from entering Greek waters by firing warning shots toward boats, the evidence indicates the persistent refusal to uphold democratic values, human rights and international and European law.”

According to UNHCR data, since the start of the pandemic, Libyan authorities – with Italian support since 2017, when Rome ceded responsibility for overseeing Mediterranean rescue operations to Libya – intercepted and pushed back to Tripoli about 15,500 asylum seekers.
The controversial strategy has caused the forced return of thousands to Libyan detention centres where, according to first hand reports, they face torture.
Hundreds have drowned when neither Libya nor Italy intervened.

 
SOS Méditerranée operates the Ocean Viking, one of the few remaining NGO rescue boats in the Mediterranean
Photograph: Flavio Gasperini/SOS Mediterranee

“In 2020 this practice continued, with an increasingly important role being played by Frontex planes, sighting boats at sea and communicating their position to the Libyan coastguard,” said Matteo de Bellis, migration researcher at Amnesty International. “
So, while Italy at some point even used the pandemic as an excuse to declare that its ports were not safe for the disembarkation of people rescued at sea, it had no problem with the Libyan coastguard returning people to Tripoli. Even when this was under shelling or when hundreds were forcibly disappeared immediately after disembarkation.”

In April, Italy and Libya were accused of deliberately ignoring a mayday call from a migrant boat in distress in Libyan waters, as waves reached six metres.
A few hours later, an NGO rescue boat discovered dozens of bodies floating in the waves.
That day 130 migrants were lost at sea.

In April, in a joint investigation with the Italian Rai News and the newspaper Domani, the Guardian saw documents from Italian prosecutors detailing conversations between two commanders of the Libyan coastguard and an Italian coastguard officer in Rome.
The transcripts appeared to expose the non-responsive behaviour of the Libyan officers and their struggling to answer the distress calls which resulted in hundreds of deaths.
At least five NGO boats remain blocked in Italian ports as authorities claim administrative reasons for holding them.

Malta, which declared its ports closed early last year, citing the pandemic, has continued to push back hundreds of migrants using two strategies: enlisting private vessels to intercept asylum seekers and force them back to Libya or turning them away with directions to Italy.

“Between 2014 and 2017, Malta was able to count on Italy to take responsibility for coordinating rescues and allowing disembarkations,” said De Bellis.
“But when Italy and the EU withdrew their ships from the central Mediterranean, to leave it in Libya’s hands, they left Malta more exposed. In response, from early 2020 the Maltese government used tactics to avoid assisting refugees and migrants in danger at sea, including arranging unlawful pushbacks to Libya by private fishing boats, diverting boats rather than rescuing them, illegally detaining hundreds of people on ill-equipped ferries off Malta’s waters, and signing a new agreement with Libya to prevent people from reaching Malta.”

Last May, a series of voice messages obtained by the Guardian confirmed the Maltese government’s strategy to use private vessels, acting at the behest of its armed forces, to intercept crossings and return refugees to Libyan detention centres.

In February 2020, the European court of human rights was accused of “completely ignoring the reality” after it ruled Spain did not violate the prohibition of collective expulsion, as asylum applications could be made at the official border crossing point.
Relying on this judgment, Spain’s constitutional court upheld “border rejections” provided certain safeguards apply.

Last week, the bodies of 24 migrants from sub-Saharan Africa were found by Spain’s maritime rescue. They are believed to have died of thirst and hunger while attempting to reach the Canary Islands.
In 2020, according to the UNHCR, 788 migrants died trying to reach Spain.

The Guardian has approached Frontex for comment.
Previously the agency has said it will be “co-operating fully” with Olaf.
 
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Wednesday, May 5, 2021

What is an 'internal wave'? It might explain the loss of an Indonesian submarine

An image taken by NASA's Aqua satellite as it passes over Indonesia, captures evidence of an internal wave in the same general area where the KRI Nanggala submarine disappeared earlier this month.Jeff Schmaltz/, MODIS Land Rapid Response Team, NASA GSFC
 
From NPR by Scott Neuman 
 
No official cause has yet been established for the destruction of an Indonesian submarine with 53 people aboard earlier this month, but some speculation has zeroed in on an undersea phenomenon which has been noted by submariners since at least World War II, though it has become better understood only in recent decades.

A senior Indonesian navy official suggested earlier this week that an "internal wave" may have pushed the KRI Nanggala 402 below its crush depth, causing the loss of the vessel and all aboard.
He cited satellite images showing the presence of such a wave in the area at about the time the sub disappeared.
 
Such waves — while seldom noticed by observers on the surface — can reach dizzying undersea heights and therefore cause concern for submarines, scientists say.
They are generated by the interplay of strong tides, warmer and cooler ocean layers and the undersea geography.
 

Internal tides, or internal waves, can reach hundreds of feet underneath the ocean surface, but might only be a few inches high on the surface.
Even though they’re underwater, NASA can see these tides from satellites.
They provide oceanographers with a unique way to map and study the much larger internal water motion.
 
Internal waves occur in specific ocean regions around the world – places such as the Strait of Gibraltar that links the Mediterranean with the Atlantic Ocean, parts of the Western Pacific and the South China Sea.
They are also known to exist in the Lombok Strait area in Indonesia, where the Nanggala was lost.

Matthew Alford, the associate director of the Marine Physical Laboratory at the Scripps Institution of Oceanography in San Diego, says that the U.S., China and Russia "have spent a lot of money" studying internal waves in the South China Sea because of their potential impact on naval operations in the strategic waterway.

"[I]nternal waves are very strong and are a hazard because they sweep ocean layers (and potentially anything in them including divers or subs) downwards hundreds of meters in just a few minutes," Alford says in an email to NPR.
"Lombok Strait is also a known region of strong internal waves," Alford, who researches the phenomenon, says.
Though he has never before heard of an internal wave sinking a submarine, it is a "plausible" scenario, Alford says.
 
A photo released on Sunday by the Indonesian navy shows parts of submarine KRI Nanggala that sank in the Bali Sea. Officials now speculate that the loss of the sub could have been caused by an internal wave.
Indonesian Navy/AP

A 1966 study by the U.S. Navy noted that "The passage of large-amplitude internal waves could make submarine depth control difficult, particularly when the submarine is running quietly at low speed."
The report, titled Internal Waves: Their Influence Upon Naval Operations, added that such waves "could initiate uncontrollable sinking of a submarine."

In World War II, submariners avoided the Strait of Gibraltar partly because they were aware of its reputation for propagating unusual undersea waves that were considered hazardous, David Farmer, a physical oceanographer at the University of Rhode Island, told USA Today in 2014.
 

Internal waves in the Strait of Gibraltar. Computer Graphics Animation of the outputs of a numerical model run in the Strait of Gibraltar showing the phenomenon of the internal waves produced by tides. Physical Oceanography Group University of Málaga (Spain)
 
At the height of the Cold War in 1984, a Soviet submarine that was apparently running beneath a tanker to mask its exit from the Strait suddenly smashed into the tanker's hull, causing damage to both vessels and forcing the submarine to surface.
The collision is thought to have been caused by an internal wave that unexpectedly thrust the submarine toward the surface.

Maarten Buijsman, a marine scientist at the University of Southern Mississippi, agrees that it's possible that an internal wave could have caused the sinking of the Nanggala.
"Some internal waves can have large amplitudes and they can displace submarines," he says.

The waves "are generated over steep topography due to the surface tides," he tells NPR. "In the South China Sea, internal wave amplitudes can be about 100 meters (330 feet)."

In the case of the Nanggala, what happened may have been the exact opposite of what occurred with the Soviet submarine in the Strait of Gibraltar in the 1980s – instead of an internal wave causing the submarine to hurtle toward the surface, the Indonesian vessel may have been pushed much deeper than it was designed to safely operate.

The Nanggala's demise is still under investigation. According to Indonesian Adm. Yudo Margono, the vessel was located in at least three pieces on the ocean floor at a depth of nearly 840 meters (2,750 feet) — far deeper than the submersible's "collapse depth" of 200 meters (655 feet).
 
An internal wave is just one possible explanation for the destruction of the German-built diesel-powered submarine.
Although it underwent a refit in South Korea that was completed in 2012, it was an old boat — having gone into service with the Indonesian navy in the early 1980s.

Nanggala was also reportedly preparing for a torpedo exercise at the time radio contact was lost — and torpedo accidents have been the cause of some high-profile submarine losses in the past.
In August 2000, an explosion of a torpedo in a tube aboard the Russian submarine Kursk set off the other torpedoes, causing the sub to go down in the Barents Sea, with all 118 of its crew, according to an official investigation.

Decades earlier, in 1968, the nuclear-powered USS Scorpion was lost with its 99 crew.
The cause of the Scorpion's sinking has never been conclusively proved, but one theory suggests that the submarine succumbed to a "hot-run" torpedo that unexpectedly became active while still in its tube.

During a media briefing in Jakarta earlier this week, Rear Adm. Iwan Isnurwanto, himself a former submariner, painted a grim picture of KRI Nanggala's final moments.
If it was an internal wave, he said, "that would be nature we are up against."
"We would be dragged by the waves, sending us to a quick descent," he said, adding, "No one can fight nature."
 
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