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The role of autonomous ships in a world wary of pandemics

Image Credit: Alejandra Sarmiento / VentureBeat

From Venture Beat by Paul Sawers

COVID-19 is accelerating technological advances across just about every industry, from robotic baristas that promote social distancing to AI and remote collaboration tools that help manual laborers get back to work.
The pandemic has had a direct impact on the transport realm, with social distancing measures calling traditional modes of travel into question.
Demand for ride-hailing services quickly plummeted with the advent of the pandemic, leading Uber to double down on food delivery and micromobility, while drone deliveries soared.
And while autonomous vehicle companies have faced significant obstacles to real-world testing, early signs suggest the crisis could hasten the adoption of driverless vehicles.

But automobiles, trucks, and drones are only part of the autonomous transport picture.
Ships and other seafaring vessels play a huge role in the global economy.
As lockdowns ease and the world adapts to a new paradigm, maritime automation could gain significant traction.

Not shipshape

According to the International Chamber of Shipping (ICS), maritime vessels constitute around 90% of all international trade — making them, as ICS puts it, the “lifeblood” of the global economy.
But boats are also floating petri dishes.

In The Geography of Transport Systems (2020), Dr. Jean-Paul Rodrigue and coauthors drew correlations between transportation and pandemics, with specific reference to the Spanish Flu.
They highlighted one of the key reasons 100 million people died and 30% of the world’s population became ill:

One important factor why the Spanish Flu spread so quickly and so extensively was through modern transportation, which at the beginning of the 20th century offered global coverage.
The virus was spread around the world by infected crews and passengers of ships and trains, and severe epidemics occurred in shipyards and railway personnel.

In short, transportation plays a pivotal role in the spread of viruses, which is why airlines, trains, subways, taxi services, and boats saw such huge drops in usage following outbreaks of COVID-19.

Cargo and passenger ships around the world have been turned away from ports by local authorities, with as many as 300,000 merchant sailors stranded at sea for months, far beyond their contractual agreements.
In April, ICS and the International Air Transport Association (IATA) issued a joint call demanding governments “take urgent measures” to facilitate crew change flights.

While the implementation of autonomous technology is not yet widespread enough to turn the tide on COVID-19, many are already looking to the future.
And companies that have been working to bring automation to the shipping industry are now poised to enter a world wary of pandemics.

Avoidance

Tel Aviv-based Orca AI is developing a collision avoidance system that is currently being piloted by a number of shipping companies globally, CEO and cofounder Yarden Gross told VentureBeat.
The company applies its algorithms to data extracted from multiple sensors installed on a vessel, including thermal and low-light cameras, to detect and measure the distance to other vessels and objects in the water.
“We then provide [a] risk assessment of any detected object and vessel to enable the crew to be more aware of potentially dangerous situations,” Gross said.

Above: Orca AI

While radar and other systems have long been used at sea, they may require constant monitoring and can’t always alert crews to a hazard or issue actionable recommendations.
This problem becomes particularly pronounced when multiple vessels or obstacles are in close proximity.
Throw into the mix crowded or narrow waterways and low-light conditions and it’s easy to see why at least three-quarters of maritime accidents are caused by human error, at least according to liability claims data.

Orca AI is banking on technology to turn the tide.
“The shipping industry is one of the most conservative industries in the world, and the pandemic is creating an increased demand for digital tools, automation, and connectivity, in order to reduce the number of people involved in the whole process,” Gross said.

Above: Orca AI’s collision avoidance system at work

The transition to fully autonomous ships will take time, particularly for large vessels that travel thousands of miles between continents.
This shift could mirror the evolution of autonomous cars and trucks, beginning with semi-autonomous technologies, such as collision avoidance systems, and initially focusing on narrow use cases on predefined routes.

The vast majority of maritime accidents happen in ports, straits, and canals, which is where Orca AI is currently focused.
“This is where the existing equipment is lacking in efficiency and accuracy,” Gross said.
“Today, systems don’t take full control over vessels, but gradually there will be more autonomous capabilities.
It will be similar to aviation, where there is still a pilot, but most of the time the computer is controlling the plane and the pilot is supervising and doing other tasks.
In autonomous shipping, there will still be a crew, but there will be more and more tasks done autonomously.”

“Marine pilotage” is a term for specially trained mariners who board ships near the port to guide them through domestic waterways, often providing local knowledge of water-based thoroughfares that the captain doesn’t have.
This task is sometimes carried out “remotely,” particularly during adverse weather conditions, with pilots on smaller boats guiding a big ship to safety or offering instructions from a control center.
However, the COVID-19 crisis could be expediting such efforts, as a number of ports have been forced to embrace remote pilotage for ships or crew arriving from high-risk countries.

In late March, the Italian cruise ship Costa Diadema reported 65 cases of COVID-19 on board.
To pass through the Suez Canal without a pilot physically boarding the ship, a team on tug boats maneuvered it using radar and information from monitoring stations along the route.
Similarly, a U.K. fishing port in April introduced remote pilotage for vessels entering its harbor.

While remote pilotage might not entirely replace traditional methods, technology can make the work more efficient and safe.
Orca AI promises to help pilots do their work remotely by “streaming the data from the cameras and other sensors back to shore in real time,” Gross said.
“Orca is in discussion with a few ports regarding this.”

Going local

Norwegian chemical company Yara International and technology group Kongsberg have been working on the Yara Birkeland Autonomous Ship Project since 2017, with plans to put an electric, autonomous container ship into service.
This effort would span three ports and 12 nautical miles in southern Norway.

Above: Yara Birkeland’s proposed route in southern Norway

Above: Yara Birkeland

The ship, which sports various sensors, including radar, lidar, and infrared cameras, has an automatic mooring system — berthing and unberthing will be done without any human intervention.
Along the route, operation centers will be equipped to handle emergency situations remotely and support the onboard AI’s decision-making.

Above: Kongsberg’s operational control center for the Yara Birkeland

The Yara Birkeland will have a crew initially, and the transition to full autonomy will be done in stages, thanks in part to the development of a detachable bridge (command center).

“Even before the vessel starts its operation, there will be a level of automated capabilities for maneuvering, positioning, moorings, and supporting the crew,” An-Magritt Tinlund Ryste, product director for next-generation shipping at Kongsberg, told VentureBeat.
“We foresee that we will be required to implement new autonomous functionality gradually to verify the performance in real-life operational scenarios before we arrive at the final stages where the vessel, the connectivity solution, and the remote operation center are sufficiently tested to allow for unmanned operation.”

While the Yara Birkeland was scheduled to transition to full automation by 2022, the COVID-19 crisis has forced developers to “pause” work on the project.
Such setbacks are not ideal, but Ryste suggested the pandemic could accelerate the broader autonomous ship movement, as “ship owners and operators have an increased incentive to invest in new technology for the future, with a focus on support and surveillance from land.”

The Yara Birkeland represents part of Kongsberg’s wider effort to bring more autonomy to seafaring vessels.
The company has already developed and demonstrated autocrossing and autodocking technology, and the first “adaptive transit” passenger ferry service traveled from dock to dock earlier this year.
This was done through a collaboration between the Norwegian Maritime Authority (NMA), shipping company Bastø Fosen, and Kongsberg.
The launch kick-started a six-month trial, during which Kongsberg’s system controlled the ferry’s journey from start to finish, with a captain overseeing the trip from inside the bridge.
The next step is to install an anti-collision system, and tests are scheduled for later this year.

Kongsberg partnered in 2018 with maritime industry group Wilhelmsen to launch a joint venture called Massterly, designing land-based operation centers to monitor and control autonomous ships in Norway and further afield.
This echoes what we’re seeing in the broader autonomous vehicle realm.
Sweden’s Einride recently showcased remote driving stations where teleoperators — many of them former truck drivers — can take control of Einride’s autonomous trucks when required, with an operator able to control multiple vehicles from a single station.

Above: Einride operators will be able to control multiple autonomous trucks from a single remote station

Einride demonstrates that while some jobs will be lost to AI and automation, new ones will be created.
For autonomous shipping, this could mean new roles for staff overseeing ships remotely.
This shift will also expand the talent pool to include people in new locations.

“Remote services are here to stay,” Ryste continued.
“We see it working well for people working from home, and with more sensors and connected vessels, the need for having a service engineer on board also decreases.
This gives you access to an expert in a time zone convenient for the vessel crew.”

The pandemic will likely accelerate efforts to incorporate autonomous technology in shipping.
“I think that what has happened during the COVID-19 crisis will strengthen the argument for the push toward autonomous ships,” Kongsberg research and innovation manager Jason McFarlane told VentureBeat.
“In particular, in relation to the restriction of people’s movement and the challenges with crew changes.
Autonomous shipping, especially for unmanned vessels, should allow freight and cargo to be transported internationally and across borders without being affected by restrictions on people’s movement.”

We’ve already seen similar activity in other industries — from the passage of laws to updated corporate work-from-home policies and the adoption of new technologies.
In the shipping industry, as with others, such changes could open the door to a more permanent shift.

“The focus has changed, and we see that even if restrictions are lifted temporarily, opening up for testing new solutions might just become a permanent solution as we adapt to new methods or technology,” Ryste added.

Research in motion

Later this year, IBM and Promare — a U.K.-based marine research and exploration organization — are scheduled to send a crewless ship across the Atlantic Ocean on the route the original Mayflower traveled exactly 400 years ago.

Above: Mayflower Autonomous Ship route map

The Mayflower Autonomous Ship (MAS) is propelled by a combination of solar- and wind-generated power, with a diesel generator on board as backup.
It also sports an onboard “AI Captain” and will leverage edge computing for its AI and navigational smarts.
All the data processing must be available on the ship because a vessel in the middle of the ocean can’t rely on satellites or cloud connectivity.


The team behind the new Mayflower has trained the ship’s AI models using millions of maritime images collected from cameras in the Plymouth Sound, among other open source data sets.
The Mayflower’s AI Captain is built to detect and identify ships and buoys — as well as other hazards — and to make decisions about what to do next.
An onboard automatic identification system (AIS) can also access specific information about any vessels ahead, including their class, weight, speed, and cargo type, while the AI Captain can accept and interpret radio broadcast warnings from a cargo ship.

Above: The Mayflower Autonomous Ship’s AI Captain in operation

This mission is mostly about showcasing how an autonomous research vessel can manage on its own for two weeks at sea, but it sets the stage for further use cases, from defense and commercial shipping to marine insurance.

“Right now, we are focused on increasing the reliability of our autonomous systems and developing an ecosystem of partners — from IBM to equipment manufacturers to telecoms providers to insurance providers — to figure out how to commercially deploy the systems we have on [the] Mayflower,” Mayflower Autonomous Ship director Brett Phaneuf said.
“What we are doing here is very much a research project for something much bigger than this one ship.”

AI and autonomy could certainly provide utility beyond cargo vessels.
Research ships may spend weeks or months at sea collecting data about the ocean, and removing crews would facilitate longer missions by taking food storage and personal well-being out of the equation.
In terms of the COVID-19 crisis, more automation could mean fewer people on board, which should help with social distancing efforts.

“We are already seeing the early examples of autonomous ferries, cargo ships, and research vessels like the Mayflower Autonomous Ship,” Phaneuf continued.
“But perhaps the greater, more immediate need for autonomy is on manned vessels.
This may sound counterintuitive, but there is an important role for autonomous systems on the manned ships of today, acting as a cocaptain, maintaining situational awareness, [and] providing recommendations and decision support to the human crew.”

We’re talking about “augmented intelligence,” as Phaneuf puts it, with machines helping people accomplish core tasks and reduce risks.

“A trusted autonomous system can reduce the stress on the bridge by consistently monitoring the overall navigational situation of the vessel,” Phaneuf added.
“This will allow humans to get their heads up and out of the computer screens and instead looking out the window and doing what humans do best — making complex decisions swiftly and accurately.”

It might not make sense for certain types of vessels to become completely autonomous, whether for logistical, regulatory, or financial reasons.
“This is not likely to be a zero-sum game, but more of a hybrid approach,” Phaneuf continued.
“For example, it may not make sense to replace the whole crew of a container ship with a fully autonomous system because the cost of the crew actually represents very little in the overall value of the ship and its cargo.
As such, there may not be an economic driver for this level of change.
However, there are other factors to take into consideration — such as the well-being of the crew and equipping people with the skills they need for the shipping industry jobs of the future.”

The future of autonomous shipping

Many newer ships are already highly automated, at least in terms of being able to passively gather performance metrics for remote analysis, and technology can also enable diagnostics and repairs from afar.
But the pandemic has highlighted the role automation can play.

Global trade today relies on ships and crews traversing vast oceans, and fully autonomous cargo vessels that can cover these distances are likely still a long way off, if they ever arrive.
Barriers include technological and regulatory constraints, not to mention practical obstacles, such as the need to carry out maintenance on longer voyages.
Domestic journeys are a natural starting point for autonomous ships because they don’t require international cooperation, and a vessel that remains relatively close to shore — such as the Yara Birkeland on its proposed route in southern Norway — can adhere to safety standards with on-shore personnel able to physically (or remotely) intervene in an emergency.

“From a regulatory perspective, the challenge (with longer, international automated routes) lies within the fact that the IMO (International Maritime Organization) does not have a common and internationally acknowledged way of granting approval [for] such vessels as the Yara Birkeland,” Ryste said.
“This means there is a likelihood of encountering varying rules and regulations between flag states and port authorities.
This is manageable for point-to-point operation but will be a too-demanding administrative task when more parties are involved — at least, at the moment.”

As COVID-19 shifts global structures and accelerates innovation, we’re already seeing how autonomous tools could help ships continue operating through future pandemics.
And while some jobs will likely be lost as automation takes hold, technology is unlikely to replace humans across the board.

“For decades, autonomous systems have been used to assist humans in dangerous work, such as clearing up after accidents or dealing with highly dangerous substances or infectious diseases,” Phaneuf noted.
As autonomous systems improve, their role “will likely increase, but [it] will need to be part of a larger, interconnected network of manned, unmanned, automated, and autonomous systems on water, in air, and on land.”

Links :

• GeoGarage blog : Rolls-Royce demonstrates fully autonomous ... / Unmanned ship to go on 400-year-old ... / Rising accidents and crowded oceans: will ...  /

The Long Blue Line: How 80 Coast guardsmen saved an Alaskan town during the Spanish flu pandemic of 1919

 Coast guard-manned USS Unalga underway in an Alaskan ice field. (NOAA)

From CoastGuard blog by BM1 William A. Bleyer, United States Coast Guard

Occasion sometimes aris in which the officers and crews are called upon to face situations of desperate human need which put their resourcefulness and energy, and even their courage, to the severest test.

“The Influenza at Unalaska and Dutch Harbor,” U.S. Coast Guard Annual Report, 1920

As the testament above indicates, The Coast Guard’s response to the Spanish Flu Pandemic in Alaska would prove the ultimate test of bravery and endurance.

Pandemic, quarantines, social distancing and facemasks–too familiar today.
These terms resonated with equal disquiet for Americans 100 years ago as the Spanish Influenza Pandemic of 1918-1919 affected nearly every corner of the globe.
It caused the deaths of between 25 and 50 million people, more than all who died in World War I.
Even in regions with the most advanced medical care, Spanish Influenza killed approximately three percent of all victims.

Crew members of Unalga burying the dead at the Russian Orthodox Cathedral. (NOAA)

Medical care in the remote territory of Alaska was far from advanced.
When the pandemic arrived in the spring of 1919, it wiped out entire villages.
At the time, Alaska was “an American colony [which] occupied a political status somewhere between a government protectorate and an industrial resource”1 and the presence of Federal Government assets in this immense territory was minimal.

In late May 1919, USS Unalga was patrolling in Seredka Bay off Akun Island, in Alaska’s Aleutian Island chain.
World War I had ended just six months prior, so – like all Coast Guard-manned cutters – Unalga and its crew still served as part of the U.S. Navy.
At 190 feet, the Unalga’s white hull was only somewhat longer than modern Fast Response Cutters patrolling Alaska’s waters today.
And while Unalga’s daily operations were fundamentally similar to today’s FRCs, they were much broader.
An Alaskan patrol in 1919 could consist of law enforcement boardings of fishing and sealing vessels; inspecting canneries; transporting mail, supplies, passengers, and prisoners; rescuing shipwrecked or stranded victims; rendering medical care; acting as a floating court; and resolving labor disputes.

On May 26th, Unalga was resting at anchor following a routine day of seamanship and signals training.
At around 4 p.m., an urgent radio message arrived.
The settlement of Unalaska on nearby Unalaska Island was suffering from a severe outbreak of Spanish Influenza.
The cutter’s commanding officer, Capt. Frederick Dodge, prepared to get the Unalga underway at dawn.

Members of Unalga’s crew shepherding orphan children to safety.

(NOAA)

That night, Unalga received another radiogram–the region around Bristol Bay, on Alaska’s southwestern mainland, needed urgent help to cope with its own outbreak.
Dodge faced a dilemma: the Unalga could not be in two places at once.
He radioed his command that he was setting a course for the closer Unalaska to assess the situation.

Remote even today, in 1919 Unalaska and adjacent Dutch Harbor were tiny villages with a combined population of about 360 people, mostly of Aleut or mixed Russian-native ancestry.
There was only one doctor on the entire island.

After arriving, Unalga’s crew disembarked to a horrific scene.
Nearly the entire settlement was infected, including the only doctor and all but one operator at Dutch Harbor’s Navy radio station.
The situation was critical as historian Alfred Crosby noted in America’s Forgotten Pandemic:

very large proportions of isolated populations tended to contract Spanish Influenza all at once.
The sick outnumbered those doing the nursing.
The sick, therefore, lacked fluids, food, and proper care, which caused very high death rates… effective leadership was vital to keeping death rates down.
If complacency, incompetence, sickness, or bad luck crippled the ability of the leaders to react efficiently to the pandemic, then Spanish Influenza could be as deadly as the Black Death.

A building commandeered by Unalga’s commanding officer, Captain Frederick Dodge, and named “USS UNALGA ORPHAN HOME.” (NOAA)

It now fell to the men of the Unalga to provide lifesaving leadership and medical care.

Out of the Unalga’s crew of approximately 80 men, only three had medical training: Ship’s Surgeon Lt. j.g. Dr. F.H. Johnson (U.S. Public Health Service), Lt. E.W. Scott (U.S. Navy Dental Corps), and Pharmacist’s Mate 1/class E.S. Chase.
These men began coordinating the town’s medical care.
Together, they assembled a group of volunteers from the crew that kept growing until it included personnel drawn from every department on board the cutter.

From May 26th to June 4th, Unalga proved the difference between life and death for the inhabitants of Unalaska.
Captain Dodge initiated feeding the town using Unalga’s food stores.
Crewmembers delivered 350 prepared meals on the first day and, by the height of the pandemic, they were delivering more than 1,000 meals per day.
Villagers ranked the ship’s emergency rations somewhere between awful and lousy, but they ate them.

Orphans and a caretaker at the Unalga Orphan Home.

(NOAA)

Every crewmember engaged in some aspect of relief work.
Nicknamed “gobs,” those not caring for the sick provided logistical support, such as keeping fires for incapacitated villagers or helping prepare or deliver food.
Other crewmen took over operation of the Navy radio station in Dutch Harbor.
The men even built a temporary hospital outfitted with plumbing and electrified by the cutter’s generator.

Caring for the sick and burying the dead was an exhausting and emotionally challenging job.
Death by “The Spanish Lady” (the disease’s elegantly macabre nickname) was often horrific.
Victims frequently suffered from double pneumonia and drowned when their lungs filled with fluid, some of it oozing out of their noses and mouths when they died.
The crewmembers nursed the sick with no protective equipment except cloth facemasks, exposing themselves to infection.
Several men became ill, including Dodge.
He determined he was well enough to remain in command and later recovered.
While Unalga’s crew did their best to save lives, they ultimately had to inter 45 victims beneath white Russian Orthodox crosses in Unalaska’s cemetery.

Unalga’s crew wearing “Flu” masks.

All the cutter’s crew members involved in the humanitarian effort volunteered to help.

(NOAA)

Unalga’s crew also cared for the children of the deceased or incapacitated.
Unlike seasonal flu, Spanish Influenza acutely affected young adults, probably because it provoked an overreaction in the victims’ immune system.
This had the tragic effect of creating a number of orphans.
Even if not infected, these children were vulnerable to starvation, freezing, or attack by feral dogs, described by Unalga’s men as similar to ravenous wolves.
Unalaska had its own orphanage, the Jesse Lee Home, but when that filled up, a vacant house was requisitioned and named the “USS UNALGA Orphan Home.”
When that also filled, Dodge started housing children in the town jail under the care of the town marshal.
Among these orphans was Benny Benson, who later designed the state flag of Alaska.

Unalga’s Master-at-Arms, Peter “Big Pete” Bugaras volunteered to care for the orphans.
An enlisted man responsible for enforcing ship’s discipline and handling prisoners, Bugaras had a reputation as “the strongest man in the Coast Guard Service,” and was described as “Greek by birth, a born fighter of men, and protector of all things helpless and small.” Burly and big-hearted, Bugaras took responsibility for running the UNALGA Orphan Home.
He had his men fashion clothes for the children by tracing outlines of their bodies on bolts of cloth and cutting them out.
Several women in the village were appalled to see Bugaras enthusiastically scrubbing children clean with the same vigor he used on dogs, but by all accounts the little ones loved him.

Outside help finally arrived on June 3rd, when Coast Guard Cutter Bear dropped anchor.
Under the combined effort of the two cutter crews, many of the surviving victims began to recover and the pandemic subsided.
Navy vessels also arrived.
In the words of Unalga officer Eugene Coffin: “Navy ships and nurses were sent to Unalaska after we yelled for them.” With the arrival of warships USS Vicksburg and USS Marblehead in mid-June, Dodge resupplied the Unalga to set sail for Bristol Bay.
Unalaska’s last death occurred June 13th and with its departure on June 17th, the Unalga’s relief of Unalaska officially ended.

Unalga men burying the dead at the Russian Orthodox Cemetery in Unalaska.

(NOAA)

The Unalga’s care of Unalaska’s inhabitants had been somewhat rough-hewn but effective.
During the cutter’s relief effort, the local mortality rate had hovered around 12 percent, while other areas in Alaska experienced up to 90 percent.

The Coast Guardsmen of the Unalga were far from saints, but for years later the inhabitants of Unalaska remembered them as saviors.
In July 1919, Unalaska’s Russian Orthodox priest, Dimitri Hotovitzky, and Aleut Chief, Alexei Yatchmeneff, co-wrote a letter to Dodge stating “We feel had it not been for the prompt and efficient work of the Unalga, when everyone willingly and readily exposed himself to succor the sick, Unalaska’s population might have been reduced to a very small number if not entirely wiped out.”

While Unalga’s performance at Unalaska drew universal acclaim, the cutter and USS Marblehead were criticized for arriving in the Bristol Bay region too late to make a difference.
As the disease had largely run its course, Unalga’s crew worked with the Marblehead’s Navy personnel to provide for the remaining medical care and relief work in the community.
When the pandemic finally released Alaska from its grip, nearly 3,000 inhabitants had died.
Nearly all of the dead were Native Alaskans, an irreparable loss to the indigenous community and its culture.

Unalga’s officers, including: Standing: Lieutenant Junior Grade Willie B. Huebner USNRF; Captain Eugene Auguste Coffin USCG; Captain Warner Keith Thompson USCG; Captain Theodore Graham Lewton USCG; Lieutenant E. W. Scott USNRF (Dental Corps); Lieutenant Junior Grade Dr. F. H.

Johnson USPHS.

Sitting: Lieutenant Carl E. Anderson USNRF; Senior Captain Frederick Gilbert Dodge USCG; Lieutenant Gordon Whiting MacLane USCG.

Every pandemic and its tragedies are unique, but in the Coast Guard’s response today we can hear echoes of 1919, when the crew of Coast Guard Cutter Unalga quarantined and rendered pandemic relief to the remote Alaskan settlement of Unalaska.
Cutter Unalga and the men who sailed aboard it made history as part of the lore of Alaska and the long blue line.

Greenland's melting ice sheet has 'passed the point of no return,' scientists say, dooming it to disappear

Ice melted during a heat wave in Kangerlussuaq, Greenland on August 1, 2019.
Caspar Haarloev from "Into the Ice" documentary via Reuters

From BusinessInsider by Morgan McFall-Johnsen

Rising temperatures have driven Greenland's glaciers past a critical tipping point, where snowfall can no longer replenish melting ice.

• Greenland's ice sheet may have passed a point of no return, setting it on an irreversible path to disappearance, according to researchers at Ohio State University.
• Snowfall can no longer replenish the ice lost as Greenland's glaciers retreat, so it will keep melting and cause catastrophic sea-level rise, even if global temperatures stop rising.
• The climate crisis could bring about other tipping points in the Arctic and the Amazon, but there may still be time to avoid those.

Greenland's ice sheet may have hit a tipping point that sets it on an irreversible path to completely disappearing.

Snowfall that normally replenishes Greenland's glaciers each year can no longer keep up with the pace of ice melt, according to researchers at Ohio State University.
That means that the Greenland ice sheet — the world's second-largest ice body — would continue to lose ice even if global temperatures stop rising.

 The Brückner and Heim glaciers in southeast Greenland.

Greenland is the second largest ice cap in the world after the Antarctic.

Jeremy Harbeck / NASA / AFP

 Heim glacier in the GeoGarage platform (DGA Denmark nautical arster chart)

In their study, published Thursday in the journal Nature, the scientists reviewed 40 years of monthly satellite data from more than 200 large glaciers that are draining into the ocean across Greenland.

"What we've found is that the ice that's discharging into the ocean is far surpassing the snow that's accumulating on the surface of the ice sheet," Michalea King, the study's lead author and researcher at Ohio State University's Byrd Polar and Climate Research Center, said in a press release.

Complete melting of the Greenland ice sheet could raise sea levels 23 feet by the year 3000.
If that happens, the ocean would swallow coastal cities across the globe.
Greenland's ice is already the world's largest single contributor to sea-level rise.
In just the next 80 years, its current melt rate would add another 2.75 inches to global sea levels, according to a study published in December.

Satellite image shows meltwater ponding on the surface of the ice sheet in northwest Greenland near the sheet’s edge on Monday, July 30, 2019.

While the heat wave broke in Western Europe after a few days, extreme temperatures shifted north and caused massive ice melts in Greenland and the Arctic.NASA via Associated Press

"Glacier retreat has knocked the dynamics of the whole ice sheet into a constant state of loss," Ian Howat, a glaciologist and co-author on the paper, said in the release.
"Even if the climate were to stay the same or even get a little colder, the ice sheet would still be losing mass."

But this is just one of many climate-change tipping points that human activity might bring about.
There is still time to avoid irreversible pathways to other calamities.

There are more points of no return

The amount of ice Greenland loses each year has steadily increased in the last two decades.
Before 2000, the researchers found, the ice sheet had an equal chance of gaining or losing mass each year.
But in the climate of the last 20 years, it will only gain mass one in every 100 years, the researchers found.

Greenland dumped an unprecedented amount of ice and water into the ocean during the summer of 2019, when a heat wave from Europe washed over the island.
The ice sheet lost 55 billion tons of water over five days — enough to cover the state of Florida in almost five inches of water.

Ice melt formed whitewaters in Kangerlussuaq, Greenland on August 1, 2019. 

Caspar Haarloev from "Into the Ice" documentary via Reuters

Melt brings about more melt, as water pooling across the ice sheet absorbs more sunlight and further heats everything around it.
That's why tipping points like Greenland's accelerate ice loss so much.

Rising global temperatures and certain human activities can bring about tipping points in other parts of the world, too.

In the Arctic, ice melt is exposing permafrost — frozen soil that releases powerful greenhouse gases when it thaws.
If warming thaws enough permafrost, the gases released will trap heat faster than humans' fossil-fuel emissions.

In the Amazon rainforest, humans have been cutting and burning trees for years, allowing moisture to escape the ecosystem.
Enough deforestation could trigger a process called "dieback," in which the rainforest would dry up, burn, and become a savanna-like landscape, releasing up to 140 billion tons of carbon into the atmosphere.
Last year, leading rainforest scientists warned that the Amazon is "teetering on the edge" of that threshold.

  In this aerial view melting ice forms a lake on free-floating ice jammed into the Ilulissat Icefjord during unseasonably warm weather on July 30, 2019 near Ilulissat, Greenland.

Still, scientists say that switching to less carbon-intensive forms of energy, like solar power, and reducing unsustainable logging and mining can help us avoid those disasters.

Even for the Greenland ice sheet, the future holds more tipping points — degrees of collapse that will accelerate the glaciers' melt even more.
Limiting global warming could delay those tipping points and give the world more time to prepare.

"We've passed the point of no return, but there's obviously more to come," Howat told CNN.
"Rather than being a single tipping point in which we've gone from a happy ice sheet to a rapidly collapsing ice sheet, it's more of a staircase where we've fallen off the first step but there's many more steps to go down into the pit."

Links :

• InsideClimate News : Going, Going ... Gone: Greenland’s Melting Ice Sheet Passed a Point of No Return in the Early 2000s
• CNN : Greenland's ice sheet has melted to a point of no return, according to new study / Ocean warming is causing massive ice sheet loss in Greenland and Antarctica, NASA study shows
• BBC :  Climate change: Satellites record history of Antarctic melting
• ArcticToday : Greenland’s ice has shrunk beyond return, a new study finds 
• National Geographic : Arctic summer sea ice could disappear as early as 2035
  
• NYTimes : Konrad Steffen, Who Sounded Alarm on Greenland Ice, Dies at 68 
• GeoGarageblog : Greenland's melting ice raised global sea ...   / Greenland's ice sheet melting seven times ... / Greenland's melting ice may affect ...  / Greenland is melting away before our eyes / Greenland lost 2 billion tons of ice this week ...

Norway (NHS) layer update in the GeoGarage platform

143 nautical raster charts updated

see GeoGarage news