Saturday, July 3, 2021

Antarctica: A place of marvel

It’s not every day that you get to spend three hours in a two-person submarine driving around the Antarctic sea floor.
And yet, there we were, at the bottom of the globe, about 700 feet under water, in a cold, pitch-black abyss positioned nervously somewhere between claustrophobia and agoraphobia.
Reporter: Ian Urbina


Friday, July 2, 2021

HMS Defender incident: what the law of the sea says

On Wednesday last week, U.K. guided-missile warship HMS Defender was overflown by Russian fighters and tailed by patrol craft while transiting an international shipping channel near Crimea.
From The Conversation by Andrew Serdy

There are conflicting accounts from the UK and Russia about an incident off Cape Fiolent on the Crimean peninsula on June 23 when Russia’s defence ministry said its aircraft had fired warning shots at the British destroyer HMS Defender to expel it from Russia’s claimed territorial sea.

The geopolitics that might lie behind the episode are for others to debate, but having credible legal arguments is always important.
The UK’s Ministry of Defence said on Twitter
The Royal Navy ship is conducting innocent passage through Ukrainian territorial waters in accordance with international law.
“Innocent passage” for foreign ships is the main qualification on a coastal state’s otherwise untrammelled sovereignty over its territorial sea of 12 nautical miles.
Several provisions are devoted to it in Part II of the 1982 United Nations Convention on the Law of the Sea (UNCLOS), to which both the UK and Russia (as well as Ukraine) are party.

Under Article 17 of UNCLOS, innocent passage is the right to proceed through another country’s territorial waters without interference.
Article 18 defines “passage” as navigation through the territorial sea of a coastal state without calling into one of its ports – as HMS Defender was doing – or to or from the internal waters of a state.
It must be “continuous and expeditious”, without stopping and anchoring, except in so far as is incidental to ordinary navigation, or because of force majeure or distress, or in order to render assistance to another vessel in distress.

Nothing suggests that HMS Defender’s passage was anything but continuous and expeditious.
As for what is “innocent”, UNCLOS Article 19 equates this with not being prejudicial to the peace, good order and security of the coastal state, and contains an exhaustive list of prejudicial acts, including use or threat of force, weapons exercises, defence- or security-related information-gathering, propaganda, smuggling of goods or people, launching, landing or taking on board aircraft or military devices, fishing, wilfully polluting and a few others.
UK within its rights

All of this points to the UK being within its rights to send its ship through the territorial waters off the Crimean peninsula.
Notably, there is no requirement that innocent passage must be done for a particular purpose, nor does it need justification in terms of the directness of the route from port of origin to destination (although a glance at the map shows that passing close to Crimea is indeed the shortest way from Odessa to any Georgian port).
Black Sea: the waters off Crimea are part of the route from Odessa to any Georgian ports.
visualization with the GeoGarage platform (NGA nautical raster chart)

So far there has been no accusation from Russia that HMS Defender was engaged in any of the acts that by UNCLOS Article 19 render passage non-innocent, which would have triggered Article 25 permitting the coastal state to take the necessary steps in its territorial sea to prevent passage which is not innocent.
It seems to have been its mere presence that Russia found objectionable, possibly because HMS Defender was too close for comfort to the sensitive naval port of Sevastopol.

The UK maintains that the ship was in a recognised sea lane.
This appears to be an indirect reference to UNCLOS Article 22, which permits the coastal state to “require foreign ships exercising the right of innocent passage through its territorial sea to use such sea lanes … as it may designate or prescribe for the regulation of the passage of ships”.

Sea lanes off southwestern Crimea were already included in the 2013 edition of the Ships’ Routeing publication of the International Maritime Organization (the UN specialised agency for shipping), the last that predates the 2014 Russian takeover of Crimea.
The current (2019) edition is behind a paywall, but it would not have been in Russia’s interest to alter the lanes since then, as that would invite the question of whether it has lawfully acquired territorial title to Crimea, answered resoundingly in the negative by UN General Assembly Resolution 68/262.

A different rule for warships?

One possible counterargument would be to say that warships do not in fact have the right of innocent passage, only merchant ships.
But this is a minority view and unconvincing, as it would make nonsense of much of the relevant provisions of UNCLOS.
Many of the acts identified as prejudicial under Article 19 can in practice only be done by warships, yet there is no point including them in this list if warships do not benefit from the right in the first place.

Moreover Russia – which, in the eyes of international law is considered as a “continuator” state to the former Soviet Union – is on record as taking what one might call the orthodox view.
The 1989 USA-USSR Joint Statement on the Uniform Interpretation of Rules of International Law Governing Innocent Passage confirms that:
 All ships, including warships …, enjoy the right of innocent passage through the territorial sea in accordance with international law, for which neither prior notification nor authorization is required.

The 1989 statement, on which all states can rely, goes on to say that a coastal state “which questions whether the particular passage of a ship through its territorial sea is innocent shall inform the ship of the reason why it questions the innocence of the passage, and provide the ship an opportunity to clarify its intentions or correct its conduct”.
No exchange of this type has been publicly released.
So it is not clear why Russia reacted as it did against the passage of HMS Defender, and the UK’s legal position, at least on the facts as known, appears strong.

But if the aim of the passage was to underline the UK view that the Crimea belongs to Ukraine and not Russia, given the reference in the Ministry of Defence statement to HMS Defender being in Ukrainian territorial waters, this is misconceived, as it cannot possibly advance Ukraine’s claim.
It might even be counterproductive, by giving an opening to an argument that the passage, if undertaken predominantly for propaganda purposes, becomes non-innocent under Article 19.

The China question

For the whole point of innocent passage is that, as a right, permission does not have to be sought for it, which makes it irrelevant to which state the territory in question belongs.
The same, incidentally, goes for the South China Sea, where – even now – the Royal Navy is sending a carrier group.
Innocent passage within 12 nautical miles of any feature clear of the water at high tide is a right irrespective of which of the claimants has the better case for territorial title.

The only difference is that one of them, China, is the leading proponent of the view confining innocent passage to merchant ships.
So – bearing in mind the qualification about propaganda – making a demonstration of passing through without seeking any claimant’s permission does actually serve a purpose there.

This thus calls into question the wisdom of an operation which has predictably annoyed Russia – assuming that was not in fact its sole aim.
But it does nothing to bolster Ukraine’s claim, however worthy a goal it might be to act in support of the UN’s rejection of any change in status of Crimea in 2014.

So in future the UK would be well advised to avoid relying on Ukrainian “permission” as a justification.
This would only undermine the innocent passage rule, as one imagines the US and perhaps others are forcefully pointing out to the UK behind the scenes.
Links :

Thursday, July 1, 2021

Can scientists map the entire seafloor by 2030?

From Smithsonian by Ewan Morgan

Two non-profit organizations are betting that with the help of research institutions, private vessels and new technologies, they can do just that

For nearly a decade, scientists at Monterey Bay’s Aquarium Research Institute (MBARI) have studied the topography and ecology of Sur Ridge, an underwater expanse the size of Manhattan located 37 miles off the coast of California.

While Sur Ridge, a submarine seamount made up of a series of peaks and valleys, had been known to scientists for decades, its abundant potential for aquatic life wasn’t realized until recently.
“The first time somebody actually put a [remotely operated vehicle] down there and looked at what was there was 2013,” says David Caress, principal engineer at MBARI.
“What they were doing was essentially exploration and sampling, but they discovered a spectacular ecological community." Researchers found forests of bubblegum corals, swathes of yellow coral, white sponges and a vampire squid.
“Sur Ridge is blanketed with really dense communities” says Caress, “It was clear that mapping would be useful to provide context to the ecology, and that’s where I come in.”
Determining the topography would help scientists understand currents that carry plankton to deep-water corals and sponges, which serve as the basis for the ecosystem.
MBARI owns remotely operated vehicles (ROVs) capable of exploring cold, dark ocean depths.
Between 2015 and 2020, the MBARI team carried out expeditions to map Sur Ridge, starting with lower resolution surveys and increasing in detail.
First, researchers used ship-based multibeam SONAR to survey the area at 25-meter resolution.
Then they used a Mapping Autonomous Underwater Vehicle to scan the topography at one-meter resolution.
Finally, an ROV flew three meters from the surface of Sur Ridge and used lasers, sonar, strobe lights and stereo cameras to create five-centimeter and one-centimeter resolution maps with millimeter-scale photography.

MBARI and Frame 48, a Los Angeles-based post-production company used the data to create a videodepicting Sur Ridge in high definition.
This underwater arena, of which little was known eight years ago, was now available for observation.
MBARI’s reconstruction was the most detailed visualization of a large underwater feature in the deep sea.

While the Sur Ridge project, with mapping completed on a grid with cells just a centimeter in size, represents the upper echelon of targeted seafloor mapping, just 20 percent of the world’s seafloor has been mapped to an adequate resolution—with grid cells of 100 meters or more across, depending on depth.

To combat this lack of information, two nonprofit organizations came together in 2018 to found the Nippon Foundation-GEBCO Seabed 2030 Project, an international effort aimed at mapping 100 percent of the ocean floor by 2030.
“In 2017, only 6 percent of the world’s oceans floor had been adequately mapped,” says Jamie McMichael-Phillips, the project’s director.
“Seabed 2030 was designed to accelerate this mapping, using data from academia, government, the maritime industry and citizens themselves.”
Great video feature from Bloomberg, featuring Head of the Atlantic and Indian Oceans Regional Center, Vicki Ferrini, and Jyotika Virmani from our long-standing partner, Schmidt Ocean Institute.
The Nippon Foundation, a Japanese philanthropic outfit that has projects focused on the future of the oceans, and GEBCO, a group focused on understanding the bathymetry, or depth measurement, of the oceans, want to build a comprehensive, publicly accessible map of the world’s seafloors—the GEBCO Grid.
To complete the map, the project will rely on research organizations, government entities, citizens and others to submit data.
These groups are already collecting seabed data for scientific, navigational, or nautical reasons and the GEBCO Grid provides a place where all of their data can be combined in one detailed map.

Seafloor mapping is expensive and technologically intensive, but it holds value to a wide range of fields.
Scientists can use information on the shape of the seafloor to understand a myriad of climate change processes, such as sea-level increases.
Bathymetric maps also help researchers predict the path and strength of tsunamis and enable ecologists to better understand underwater ecosystems.

“Data is used in coastal ocean science, habitat characterization, wave models, flooding models, wind energy development, all kinds of things,” says Ashley Chappell, integrated ocean and coastal mapping coordinator at the U.S. National Oceanic and Atmospheric Administration (NOAA). 

This image from Seabed 2030 shows how much of the seafloor has been mapped, with black areas representing places without data yet.
(Vicki Ferrini)
While the modern incarnation of seafloor mapping is technologically intensive, measuring depth is not a new pursuit.
Over 3,000 years ago, weighted lines and sounding poles—rods lowered into the water—were used to measure the depth of the ocean off Egypt.
In the 1870s, the HMS Challenger, a repurposed Royal Navy warship cast rope weighted with lead overboard to measure depth.
Its findings included the first recordings of the Challenger Deep, the deepest known point of the Earth’s oceans.

In the 1950s, academics produced the first physiographic map of the Atlantic Ocean floor using single-beam echo soundings, which determine water depth by measuring the travel time of a sonar pulse.
Researchers discovered a worldwide volcanic ridge system on the ocean floor, where lava emerged to form large plates that moved—helping confirm the theory that Earth’s continents drift over time.
During the late 1970s, more effective multibeam sonars became available for civilian use and were installed on academic research vessels, accelerating the field further.
Modern bathymetry now has a range of tools in its cartographic arsenal, from aircrafts using laser imaging technology (LIDAR) that map coastline areas to submersible ROVs, such as those used by MBARI.

Still, seafloor mapping is technically difficult and consequently expensive.
“An oceanographic research ship with work class deep diving ROV can easily cost $35,000 per day and rise to more than double that depending on ship size,” says Caress.
“And there’s ship and crew costs on top of that”.

Moreover, vessels using sonar have to travel fairly slowly, which is an issue when about 140 million square miles of water need to be covered.

In the last few years, though, efforts have accelerated to streamline the process and close the knowledge gap, in part thanks to Seabed 2030, which has set a tangible goal for the bathymetric community.
The project has brought together research institutions and increased citizen awareness of the importance of the seabed.
“While we were collaborating before, the project has certainly driven more collaboration,” says Chappell.
“And from my perspective, it really reinvigorated this desire we all share: to get our oceans mapped.”

Research laboratories, government entities, private companies and other organizations are contributing data to the GEBCO grid, with the understanding that it will help others across the world in a range of industries.

Hundreds of thousands of cargo vessels, fishing boats and yachts are equipped with on-board echosounders, and take routes that research organizations do not.
Utilizing data from these ships will be crucial to the project’s success.
While some citizens are already onboard and contributing data, McMichael-Phillips is counting on others to join the effort as awareness of the project grows.
Seabed 2030 is running field trials in Palau, South Africa and Greenland, where citizen vessels have been provided with inexpensive data loggers with the expectation that they will provide useful data and encourage others to do the same.

McMichael-Phillips hopes that by the end of this year the GEBCO Grid should be able to display 21 percent of the ocean seafloor to an adequate resolution.
Collaboration is key if the 100 percent figure is to be achieved by 2030.
If the project had a fleet of 200 ships patrolling and mapping the oceans 24/7, it could achieve its goal in a year.
“There are more than 200 vessels capable of deploying sonar systems,” says McMichael-Phillips, “but the cost of such a feat would be somewhere between $3 billion and $5 billion, which isn’t easy to find in the maritime domain.” Crowdsourced data is thus of utmost importance to the project.

Still, the future of seafloor mapping is looking hopeful, thanks to new technologies and increased collaboration.
For example, the Schmidt Ocean Institute, a private research organisation with a sophisticated research vessel and ROV, has pledged to share all of its mapping data with Seabed 2030.
The nonprofit is currently working with Australian research institutions to map the Tasman and Coral seas off the east coast of Australia.

And new autonomous vessels are mapping the seafloor more efficiently than crewed vessels.
In August 2020, a SEA-KIT vessel mapped over 350 square miles of ocean floor in the Atlantic Ocean while remotely controlled by a team located in Essex, England.
Such efforts are also cheaper than sending crewed vessels out, and they will need to be adopted more widely if Seabed 2030’s goal is to be reached.

“People can run uncrewed, low-carbon mapping systems from the safety of the shore,” says McMichael-Phillips.
“We’re only just seeing that technology accelerate through the maritime sector; it’s a big game changer.”
Links :

Wednesday, June 30, 2021

The mysterious case of an island that ‘vanished’ in the Gulf of Mexico

Bermeja (circled in red) on a map from 1779
Carte du Mexique et de la Nouvelle Espagne : contenant la partie australe de l'Amérique Septentle.. (LOC)
Theories of what happened to the island range from it being subject to ocean floor shifts or rising water levels to it being destroyed by the US to gain oil rights.
It also may have never existed.
From MexicoNewsDaily by Shannon Collins

Isla Bermeja, only noticed missing in 2008, may have cost Mexico millions in oil revenue

First appearing in a Spanish compendium of all the islands of the world in 1539, Bermeja has flummoxed sailors, fishermen and politicians since it seemingly vanished from the ocean around the turn of the 21st century.

22°33’N, 91°22’W.
Take a boat to these coordinates and you are almost certain to find nothing but empty water and open skies despite the fact that, dating back to the 16th century, this phantom islet in the Gulf of Mexico was clearly visible on maps and charts.

Isla Bermeja’s dematerialization only became apparent over the course of negotiations between the governments of Mexico and the United States in 2008 and 2009 over who had drilling rights to parts of the Gulf of Mexico, in which the phantom island was considered crucial for determining national marine boundaries.

Localization with the GeoGarage platform (NOAA nautical raster chart)
"There is no vestige of her island in the area probed".
Also it was determined that that location had not been any island in more than 5,300 years, as established from an analysis of the approximate age of the surface of the sea floor. 

Localization with the GeoGarage platform (NOAA nautical raster chart)
extract from chart SM030 SEMAR

“Isla Bermeja was a controversy because it was a key area of the Exclusive Economic Zone in the Gulf of Mexico,” geographer and islands specialist Israel Baxin Martínez explains.

“There were official searches around this time to see if there was some remnant of this island because the expansion of this zone for Mexico would mean an abundance of oil.”

Off the north coast of the Yucatán, it would have been the northernmost Mexican island in the gulf.
As a result of its absence, Mexico lost rights to a maritime area that was believed to hold 22.5 billion barrels of oil.

The Mexican government searched for Isla Bermeja’s remnants, hoping it would help the nation secure drilling rights in the area, says geographer Israel Baxin.

It has been speculated that the island disappeared as a result of natural geographic shifts in the ocean floor and rising sea levels that have already swallowed remote islands in Hawaii, Japan, and the Arctic.

It could also be, of course, that the island never existed and that its appearance on early maps was merely the result of erroneous observations by cartographers.

With such a plentiful stock of black gold on the line, and the complex political latticework that oil negotiations necessarily entail, conspiracy theories about the cause of the island’s disappearance abound.
El Yucatán e Islas Adyacentes in the Islario General de todas las Islas del Mundo (1539) by Alonso de Santa Cruz. Bermeja is shown circled in the upper portion (Source: BBC Mundo 2009) 

White, Gallaher & White Mapa de los Estados Unidos de Méjico 

It is even common chatter among fishing communities along the coast of the Yucatán that the island was destroyed deliberately to allow the United States to eat into the Exclusive Economic Zone.

However, when negotiations began in 2009, oil production rates had been dropping — or failing to increase — every year since 2004.
In spite of this, oil revenues count for 10% of Mexico’s export earnings, and therefore are a significant contributor to national GDP.

Notwithstanding the continuing global slump in oil demand as a result of the rise of sustainable fuel options and a more widespread awareness of the damaging effects of drilling for and burning crude oils, the loss of the territory to the U.S. represented a significant blow for economic expansion.

“It’s a conspiracy theory, of course,” an unmoved Martínez says.

A 1914 map showing US claim on "Bermejo I."
Yet the layman’s whisper has seeped into the political chat at large: in November 2008, six senators from the then governing National Action Party (PAN) raised questions about Isla Bermeja, citing suspicions that the island had been made to vanish deliberately by American powers in order to give the U.S. more leverage in negotiations over marine territory.

This, however, is a more-than-suspect allegation.
It is scarcely believable that an entire island could be destroyed or obfuscated from the map without somebody noticing, and there is already a precedent for confusion around the existence of small islets.

In the Pacific, for example, Martínez cites islands that, through issues with cartography or nomenclature, either do not exist or are existentially confused.
He cites as examples cartographical inaccuracies appertaining to the Isla de Cedros and the Revillagigedo Islands southwest of the southern tip of Baja California, a large archipelago famous for its endemic flora and fauna.

“Conceptually,” Martínez continues, “we notionally believe that everything that is mapped must exist.
So, because the island was mapped in the 16th, 17th, and 18th centuries, the assumption was that the island existed, and the map record confirms it.”

In these cases, Martinez says, the existence of the islands was “a continually unconfirmed truth,” which is as much to say that once an entity is mapped, its existence is assumed and replicated without question.

Bermeja, however, is a little different.
Historically, the island was mentioned in the cartography of explorers in the 18th century, but it is additionally mentioned in other documents, including a number of official inventories at the end of the 19th and beginning of the 20th century — some of which were government inventories.

“The question with Bermeja in particular is that it’s not just mentioned in cartographic history,” says Martínez.
“It has a much larger backlog of studies and a presence in the official inventories.”

Since 2009, there have only been four official expeditions to find Bermeja, alongside a handful of journeys by enquiring journalists and the generally curious.

In the last decade, TV Azteca and the National Autonomous University launched maritime research campaigns to locate the territory, but the missions came to the same conclusions as those sponsored by the government: that the island does not exist and that there are no vestiges of such a body of land in the area.

It is telling that there was little interest in the island until it was believed to have been taken away; like a child with toys, the Mexican cultural consciousness was uninterested in an uninhabited island miles into the gulf until it was no longer there.

“Culturally, what we see with Bermeja, as in many other cases, is that people don’t care about what they’ve got, but they do care about what they’ve lost,” Martinez reflects.
“People are jealous of what has been taken from them, but they refuse to do anything with what they already have.”

And therein — perhaps — lies a much greater truth, one that has little to do with disappearing islands and much more to do with the unquestioned lies we build up around us in order to perpetuate the myths of who we believe ourselves to be.
Links :

Tuesday, June 29, 2021

The coelacanth may live for a century. That’s not great news

Photograph: The Natural History Museum/Science Source

From Wired by Max G. Levy

Scale markings reveal that this weird fish's lifespan is double what scientists first estimated.
That also means they’re closer to extinction than we thought.

African coelacanths are very old.
Fossil evidence dates their genesis to around 400 million years ago, and scientists thought they were extinct until 1938, when museum curator Marjorie Courtenay-Latimer noticed a live one in a fisher’s net.

Found off the southeastern coast of Africa, coelacanths also live a long time—scientists have suspected about 50 years.
But proving that lifespan has been tough.
(Coelacanths are endangered and accustomed to deep waters, so scientists can’t just stick their babies in a tank and start a timer.) Now a French research team examining their scales with polarized light has determined that they can likely live much, much longer.
“We were taken aback,” says Bruno Ernande, a marine ecologist who led the study.
The new estimated lifespan, he says, “was almost a century.”

His team from the French Institute for the Exploitation of the Sea, or IFREMER, found not only that individuals can live to nearly 100 but also that they have gestation periods of at least five years, and may not mature sexually until they’re at least 40.
The results were published on Thursday in Current Biology.
This slow-motion life highlights the importance of conservation efforts for this rare species, which is marked as “critically endangered” on the IUCN Red List.
Only about 1,000 exist in the wild, and their long gestation and late maturity are bad news for their population’s resilience to run-ins with humans.
“It's even more endangered than we previously thought,” Ernande says.

“It will have enormous consequences,” agrees Daniel Pauly, an ichthyologist from the University of British Columbia, who was not involved in the study.
Pauly is the creator of FishBase, a database of biological and ecological information about tens of thousands of species.
If a fish takes decades to spawn, then killing it wipes out its potential to replenish the population.
“A fish that needs 50 years to reach maturity, as opposed to 10 years, is five times more likely to be in trouble,” he says.

Coelacanths have thick scales that grow up to two inches long, and for decades ichthyologists have been debating how to read those scales for signs of age.
In the 1970s, researchers noticed small calcified structures on them.
They figured the rings were age markers, like tree rings.
They disagreed, however, on how to count them: Some figured that each marking denoted one year; others believed that seasonal flips created two rings per year.
At the time, the best guess placed their life expectancy at about 22 years.
That conclusion, which meant that a 6-foot, 200-pound coelacanth is 17 years old, implied that they grow very quickly: “They would grow as fast as tuna, which is crazy,” Pauly says.

It’s crazy because these are animals with slow metabolisms, which should indicate slow growth.
Coelacanths’ hemoglobin is adapted to that slow metabolism, which means they can’t take in enough oxygen to support a fast-growing fish.
Some argue that their small gills are further evidence of oxygen limitations.
They also live very passive lifestyles, resting most of the day in caves and lumbering slowly through the ocean’s twilight zone, down at 650 feet and below, when they do deign to move around.
“Overwhelmingly, the biological features were pointing to a slow-living fish,” says Ernande.

Plus, scientists tracking the lives of individual coelacanths have known that 20 years is far too low.
In the 1980s, researchers started sending submersibles and remote-operated vehicles down to a cave harboring 300 to 400 coelacanths.
They returned to this spot for over 20 years.
During each visit, they recognized individuals by their characteristic white markings.
Only about three or four fish in this group would die, and an equal number of new ones would be born, each year.
This observation provided striking evidence that coelacanths live long lives—even more than 100 years, that study argues.

But a population assessment doesn’t pin down age or lifespan directly.
Intrigued by this gap, Ernande and his colleagues began tackling coelacanth age as a “fun side project.” He and the study’s lead author, Kélig Mahé, had been determining the ages of species that are commercially fished.
Knowing the relationship between a fish’s age and its size helps forecast—and conserve—future populations.
They figured they’d conduct a similar analysis for the coelacanth, but since they are endangered, they couldn't fish for them or find any in an aquarium.
They instead requested museum specimens from France and Germany.

Photograph: Marc Herbin/MNHN

The usual way of determining a fish's age is by looking at its otoliths, inner-ear stones that fish use for hearing; they also record the passing years as the calcium carbonate builds up.
But otoliths are inside fish heads.
Would the French National Museum of Natural History let researchers chop open their prized collection to dig out the little stone for a "fun side project"? 

The team didn’t even bother asking.

Instead they focused on examining the fish’s scales.
In previous studies devoted to counting their rings, researchers had examined them by microscope under regular light.
Mahé had something else in mind: polarized light.
Light waves normally vibrate every which way, not just the direction in which the wave is traveling.
Polarized light is like streaking a comb through messy hair—all the waves now vibrate in the same plane.
(The glare of sunlight bouncing off a river is polarized; that’s why polarized sunglasses can filter that entire bundle of rays out simultaneously.) When light hits a sample containing minerals—as calcified fish scale structures do—the polarized light exaggerates these minerals against the rest of the scale, making otherwise invisible structures visible.

The polarized light microscope revealed five times more rings in the coelacanth’s scales than anyone had seen before.
These “circuli” were much more fine than the larger and sparse “macrocirculi” that had been observed in the ’70s, and they appeared across all of the museum’s 27 specimens, which ranged from embryos to nearly full-grown adults.
Counting circuli told a completely new story: Coelacanths grow very slowly, and they can live extremely long.
A coelacanth thought to be 17 years old, if you only counted its macrocirculi, would instead be about 85.

To validate the new approach, the team charted the relationship between each fish’s size and age.
Like other fish, coelacanths should grow logarithmically—at first a period of fast growth, followed by a slow plateau as they approach a maximum lifespan.
The new ages made sense.
Smaller specimens fit neatly in the range they would expect of a fast-growing adolescent, and the largest specimens fit in a slower-growth phase that plateaued near 2 meters and around 100 years old.

The rings found on two large embryos also suggested that they gestate for at least five years.
“As far as we know, this is the longest gestation period for a fish,” Ernande says.

Coelacanths become reproductively mature when they’re about 5 feet long.
And based on the growth model for the species, Ernande’s team concluded, coelacanths don’t reach that length until they are 40 to 69 years old.
That time until sexual maturity is among the longest of any known species.

“That is crazy old,” says Prosanta Chakrabarty, an ichthyologist from Louisiana State University who is not involved in the study.
“So old that it makes me kind of dubious, to be honest.” He completely buys the team’s lifespan conclusion.
But, he says, the deduction that coelacanths can’t reproduce until halfway to two-thirds of the way into it is extraordinary.
And extraordinary claims need extraordinary evidence.

The age range for spawning may be off, since it’s deduced from previously reported sizes of mature individuals and their model for determining age from size.
To him, the team could solidify the sexual maturity conclusion by accessing one or two coelacanth otoliths or repeating the same scale analysis in other species of fish.
“It just comes down to scales,” Chakrabarty says.
“Show me that the scales on a orange roughy, which can also live 100 years, would work in the same way.” Lungfish, a fellow long-lived and limb-finned fish like the coelacanth, could also provide extra assurance in the method, he says.

Ernande shares Chakrabarty’s caution.
But since ichthyologists are fairly confident that coelacanths don’t mature while smaller, and coelacanths clearly grow slowly, Ernande is satisfied with his team’s conclusion.
“Even though it might not be 50, but 40, or 35, it's still a very old age.
That's for sure,” he says.

Photograph: Marc Herbin/MNHN

Pauly is not surprised that coelacanths take so long to mature:
“Fish don't know their age, they know their size.
When a fish gets bigger, it has more trouble breathing.
Their body grows in volume, but the gills only grow in surface area.
So as the surface-to-volume ratio decreases.
At about one third of their maximum weight, a transition to sexual maturity begins.
“This tension between the gills and the body—between the oxygen supply and the oxygen need—triggers a transition to do spawning,” Pauly says.

The coelacanth’s delayed sexual maturity and long gestation suggests that conservation efforts are extra important, because any animal that’s lost cannot be quickly replaced.
If it takes 40 years for an individual to mature and five more to gestate, removing any adult would make the population “quickly collapse,” Pauly says.

Their unique look and reputation for long life has made coelacanths vulnerable to illegal trafficking and incidental catches in Madagascar.
People in the neighboring Comoros Islands sometimes fish them as well.
“They were using the scales like sandpaper for their bicycles,” according to Pauly.

A team of divers off the coast of South Africa comes face to face with a Coelacanth.

Ernande’s team has turned their side project into a major focus area—they now plan to expand their analysis with more and larger specimens.
(Perhaps a larger coelacanth might even be older than 100.)
And a new area of focus for them will be measuring the fish’s climate resilience.
If coelacanths struggle to extract oxygen from warmer water, evidence could show up in their scale rings.
If warm water years show up as tighter rings, that’d mean they are growing slower and maturing later as the planet warms—more bad news for coelacanths.

His team won’t know until they glean more stories from the coelacanths’ anatomy.
They hope these life stories and climate stories told on a yearly timescale, printed finely on scales of a different sort, will not be cut short.
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Monday, June 28, 2021

Cloud spraying and hurricane slaying: how ocean geoengineering became the frontier of the climate crisis

Methane bubbles frozen in a lake in China.
The release of the gas as Arctic ice melts could cause 1C of global warming ‘instantly’ but geoengineering could neutralise this using an iron salt.
Photograph: Rex/Shutterstock
From The Guardian by Amy Fleming

Around the world, dozens of ingenious projects are trying to ‘trick’ the ocean into absorbing more CO2.
But critics warn of unforeseen consequences

Tom Green has a plan to tackle climate change.
The British biologist and director of the charity Project Vesta wants to turn a trillion tonnes of CO2 into rock, and sink it to the bottom of the sea.

Green admits the idea is “audacious”.
It would involve locking away atmospheric carbon by dropping pea-coloured sand into the ocean.
The sand is made of ground olivine – an abundant volcanic rock, known to jewellers as peridot – and, if Green’s calculations are correct, depositing it offshore on 2% of the world’s coastlines would capture 100% of total global annual carbon emissions.

The plan relies on a natural process called weathering.
“Weathering has been working on the planet for billions of years,” says Green, a graduate of Harvard Business School who runs Project Vesta from San Francisco.
“When rain falls on volcanic rocks, they dissolve a little in the water, causing a chemical reaction that uses carbon dioxide from the atmosphere.
The carbon ends up in the ocean, where it’s used by marine-calcifying organisms like corals and shell-making animals, whose skeletons and shells sink to the bottom of the ocean as sediment and eventually become limestone.”

Volcanic olivine, which Project Vesta is trialling as a way to capture carbon absorbed in oceans.
Photograph: Courtesy: Project Vesta

Olivine weathers easily, and allowing ocean currents to churn it up, says Green, “will make it dissolve much more quickly, to happen on a human-relevant timescale”.
It is not a rare mineral: there are beaches in the Galapagos islands and in Hawaii that are green with olivine-rich sand.

The idea of using the sea to absorb excess carbon is not far-fetched, says Green.
Ocean water can hold 150 times more CO2 than air, per unit of volume.
“The ocean has already taken up about 30% of the excess carbon dioxide that we’ve emitted as a society,” he says.
He and his colleagues are gearing up to test their process in two similar Caribbean coves, one acting as an untouched “control” in the experiment.

There remain many unknowns.
Would such an intervention work? Who gets to decide if it should go ahead? Could there be side-effects? It is complex chemistry, and the natural process of weathering would be accelerated to an unnatural pace.
Our understanding of the workings of the ocean is a mere drop in the proverbial.
But with our race to mend the planet having taken on Sisyphean overtones, there is still hope that the vast, churning seas can be our lifeline.

Increasing carbon capture naturally on land – by planting trees, for example – will not remove enough CO2 to halt global heating.
Peter Wadhams, head of the Polar Ocean Physics Group at Cambridge University and author of A Farewell to Ice, says: “If you want to get rid of the industrial emissions from Europe, you’d have to turn Europe into one big primeval forest.
It works, but it’s not good enough alone.”
The problem is so large that we cannot be focused on the idea of perfection, because perfection is the enemy of goodGaurav Sant, UCLA

There are many ingenious ideas being discussed.
Coastlines could be rewilded with underwater forests of kelp or seagrass, surface water cooled by generating air bubbles to whoosh cold water up from the deep, and marine clouds sprayed with seawater to reflect more heat from the sun.

As the UK prepares to host the UN Climate Change Conference (Cop26) in November, dozens of these projects are being trialled.
Most rely on the ocean’s many natural balance-restoring processes: enhancing them to help slow cooling, to lock away carbon, to protect Arctic ice or even to reduce the threat of hurricanes.

Nobody knows if these concepts will work, or what consequences there could be.
They all qualify as geoengineering – a dirty word for some environmentalists.
Human intervention in the natural world has often gone awry: cane toads unleashed in Australia in the 1930s to protect sugar crops continue to decimate native fauna.
And there is always the prospect of high carbon-emitting industries viewing such solutions as an excuse to dodge their emission-cutting commitments and maintain business as usual.

Gaurav Sant, director of the UCLA Institute for Carbon Management, says there is no longer time to waste debating.
“What else could happen? The short answer is we don’t know, and I don’t think anybody else does either.
We’re simply going to have to do this and find out.

Prof Gaurav Sant, at UCLA, has helped to develop technology that can extract carbon dioxide from the sea, enabling the water to absorb more.
Photograph: UCLA

“The problem at hand is so large that we cannot be focused on the idea of perfection, because perfection is the enemy of good.”

Sant is referring to another concept, which he is helping to develop just a few hundred miles down the coast from Green, where UCLA engineers have developed a machine that mimics how seashells form.
Called a flow reactor, the machine sucks seawater in, and an electrical charge makes it alkaline, which triggers the CO2 to react with the seawater’s magnesium and calcium, producing limestone and magnesite (like forming shells).
The water then flows out and, depleted of its captured CO2, is ready to take up more.
A byproduct of this process – hydrogen – can be extracted for fuel.

It’s a similar concept to weathering olivine in the ocean, and Sant’s plan is for initial small studies before a gradual scaling up.
The team aims to remove between 10 and 20 gigatonnes of CO2 from the atmosphere, starting in 2050.

Sant says it will be a huge challenge to build a system large enough – and then to build thousands more.
“Anyone saying ‘we’re going to do this in five years’, is greatly underestimating the challenge,” he says.
“We’re talking about an enormous enterprise, the size and scale of which humanity has not seen before.”

The sheer scale of geoengineering needed to tackle the climate crisis means that even well-known ideas are floundering.
The notion of boosting phytoplankton blooms, tiny floating plants that absorb CO2 when they photosynthesise, and can be helped along by nutrients, such as iron, was much mooted.

But Jean-Pierre Gattuso, research director at the Laboratoire d’Océanographie de Villefranche in Paris, says the latest research suggests the idea is not viable.
“Ocean fertilisation experiments were performed at sea demonstrating that iron addition can trigger a phytoplankton bloom,” he says.
“However, the amount of CO2 permanently sequestered appears to be small, because most of the organic matter produced is respired back to CO2before it has a chance to be stored in the deep ocean.
An unintended consequence may also be the creation of low-oxygen areas of water.”

A Nasa image of the southern Atlantic Ocean showing phytoplankton blooms (in green and light blue).
The tiny plants can sequester CO2.
Photograph: Nasa/Zuma/Rex

Another setback has arisen in the attempt to neutralise methane as it escapes from beneath melting Arctic ice.
Methane bubble plumes are increasingly being seen in the Arctic, and Wadhams is frustrated that the Intergovernmental Panel on Climate Change (IPCC) has not yet accepted his theory that, as the ice melts, we could face a catastrophic escape of methanethat has been stored for 20,000 years.
Estimates, he says, range from 50 to 700 gigatonnes, which could “cause maybe a degree [centigrade] of warming, more or less instantly”, bringing forward by 15–35 years the average date at which the global mean temperature rise exceeds 2°C above pre-industrial levels.

The best geoengineering prevention for that relies, again, on the ocean.
“If you blow a fine powder, or aerosol, of an iron salt called ferric chloride over the sea surface in the place where methane is bubbling out, it reacts with the methane, producing ferric hydroxide, which dissolves in the water,” he says.

Frustratingly for the theory’s backers, a test voyage this year by the University of Copenhagen found no evidence that it could work efficiently enough to remove the required amounts of the gas.

Wadhams is part of a group seeking other solutions, but the salt-blowing idea is the only “shot in the locker” at the moment, he says.
“The results, while disappointing, show that something is happening – it’s just not as efficient as everyone hoped.
To use a sad phrase, ‘further research is necessary’.”

A conceptual Flettner ship, which would spray seawater into the air to make clouds reflect more sunlight.Illustration: J MacNeill

Like many geoengineering ideas, a potential preventive measure that could cool Arctic waters, and thereby help to keep the methane sealed in the ice comes mired in fear and politics.
“Marine cloud-brightening” is spraying a fine mist of seawater into clouds so that the salt makes them brighter, and more reflective of the sun’s heat.

It is already being trialled as part of an Australian government-funded research programme to limit damage to the Great Barrier Reef, and Wadhams believes it could be used on a mass scale.
However, he thinks the most urgent need is to deploy it “on a more restricted scale, around the edges of the Arctic” where the methane escape risks are highest.

Vessels with tall masts would spray the seawater, in a system being developed by Stephen Salter, emeritus professor of engineering design at Edinburgh University.
Wadhams says it’s “the one major method of reducing global warming and saving us from methane attack … But there’s a lack of understanding of it, lack of vision and of course, lack of money.
It will cost a few tens of millions to get this thing going.”

With Britain hosting Cop26 in November, he says: “We can’t look inert.
The easiest thing to latch on to would be marine cloud-brightening.
It would work and achieve a great deal.”
The easiest thing to latch on to would be marine cloud-brightening.
It would work and achieve a great dealPeter Wadhams, Cambridge University

But even as Wadhams believes the process will be harmless, Ray Pierrehumbert, professor of physics at Oxford University, sees red flags.

“A lot of weather patterns like monsoons depend on the difference in heating between the continents and the oceans,” he says.
“If you do something to cool down the North Atlantic, let’s say to preserve the sea ice or Greenland glaciers, that shifts precipitation in the tropics.
Every part of the atmosphere is connected, so if you don’t balance your warming and cooling very carefully, then you get all sorts of changes in the climate system, some of which are difficult to predict.”

A graver risk, he says, is viewing technology such as this as a way to avoid reducing emissions.
“Once you emit CO2, its warming effect will continue for thousands of years.
Whereas marine cloud-brightening relies on particles that fall out of the atmosphere after, maybe, seven days.
So you have to renew them every week.
And if you come to rely on it for something like keeping the Great Barrier Reef from dying, you have to continue doing it for ever.
But all sorts of things could happen to force you to stop – wars, whatever – and if you do stop, then you get this extremely rapid, catastrophic warming.”

A bubble curtain of compressed air released to prevent Norway’s Holandsfjord freezing over.
Olav Hollingsaeter is looking at whether the concept can be used as a ‘hurricane slayer’.
Photograph: Courtesy: OceanTherm

Attempts to hack the weather are controversial.
A method of solar radiation management, supported by Bill Gates, which would involve sending particles into the stratosphere to reflect sunlight, was described as a billionaire trying to blot out the sun.
And cloud-seeding rarely appears without the accompanying phrase “playing god”.
But that isn’t deterring the people behind another new ocean geoengineering project to tackle hurricanes by cooling the surface water where they form.

In 2017, with his brother Bjorn, Olav Hollingsaeter, a former Norwegian navy submariner, started OceanTherm to repurpose established technology to reduce storm intensity.
During Norwegian winters, OceanTherm uses “bubble curtains” to release compressed air into deep water.
These push warmer water to the surface, which stops harbours freezing over.
Deploying bubble curtains in warmer waters shoots colder deep water upwards, cooling the surface.

Hollingsaeter is in talks with decision-makers in areas affected by hurricanes around the Gulf of Mexico, but his quest is complicated by legal and ethical concerns.
A similar “hurricane slayer” project by Alan Blumberg, the oceanographer behind an attempt to cool surface water by pumping colder water up, told the Washington Post in 2019 that his research stalled over fears it might change the landfall of a storm, or increase its flooding impact.

Hollingsaeter claims his design improves on Blumberg’s .
“When you’re pumping colder water to the surface, the cold water is much heavier and will sink.
But the bubble curtain mixes the water temperatures all the way up, so there’s a thick layer of cooler water.”

He admits that nobody knows if cooling surface water could change a storm’s trajectory or power but argues that the potential benefits make it worth further research.

Rewilding coastlines is perhaps an easier climate crisis mitigation plan to get behind.
There are three types of “blue carbon” coastal ecosystems that store carbon in sediment or soil: mangroves, salt marshes and seagrasses.
Together, they absorb more carbon than land forests, and the carbon escapes only if the ecosystems are destroyed.

Unfortunately, this is what has happened to half of the world’s mangroves and many salt marshes, as coastlines are cleared of natural landscapes.
In the UK alone, more than 90% of seagrass meadows have been lost to coastal development, anchor damage and algae-feeding pollution.
It’s a very careful, robust, rigorous scientific processTom Green, Project Vesta

There are efforts to restore these habitats, as well as to encourage the growth of kelp, which absorbs an estimated 600m tonnes of CO2 a year globally.
Restoration is a local issue: in the UK, Project Seagrass is laying rope and seed to create new sea meadows and the Wallasea Island Wild Coast initiativein Essex is building up salt marshes using clay, chalk and gravel dug out by the Crossrail tunnelling in London.
In Kenya, where mangrove wood is used for charcoal, shipbuilding and carpentry, conservation organisations are working together on long-term mangrove restoration projects.

Yet Gattuso believes that, while blue-carbon ecosystems need to be conserved and restored anyway, their potential effects on climate is limited.
Meanwhile, the other ocean-based measures that do not involve rewilding “are either at concept stage or risky”, he says.

“I wish that countries would put less emphasis on these approaches and return to the well-known, safe and most effective approach, which is to decrease sources of greenhouse gases,” he adds.
“This is where the urgency is.”

Sunlight streaming through a kelp forest off California’s Anacapa Island.
Globally, kelp forests absorb some 600m tonnes of CO2 a year.
Photograph: Douglas Klug/Getty

Green knows Project Vesta is going to face a lot of similar objections.
He is aware that it is not just politicians and environmentalists who need convincing, but communities living along the coasts where he wants to dump the rock.
They must be engaged with “to explain what we’re doing, address any concerns and involve them in the decision-making process”, he says, claiming his plan is to start small, test, monitor and build up only if satisfied – and only then in stages.
“It’s a very careful, robust, rigorous scientific process.”

The benefits, he argues, could be huge.
Weathering could potentially be a cheap method of carbon removal and he claims CO2 removal gains would be 20 times more than emitted in the olivine’s mining and transport.
Furthermore, unlike land-based carbon-capture ideas, weathering locks carbon away irreversibly, rather than in underground reservoirs that risk leakage.
The bonus effect, he says, is that weathering renders the carbon “like baking soda, which de-acidifies the ocean”.

Project Vesta started with funds from philanthropy and grants, but Green expects the sale of carbon credits can pay for scaling up.
“Most countries will be unable to meet their nationally determined contributions (NDCs) to emissions reductions, and will need to offset them with carbon credits,” says Green.

Critics fear that rather being the way to achieve net-zero carbon, it will be a licence to keep burning fuel.
“Sometimes people say to me, ‘doesn’t this create a moral hazard?’” says Green.
“‘Will that not remove the incentive for people to cut emissions?’ And the answer is very clear: we need both.”

He believes that, ultimately, the carbon market will “sort it out.
If companies have to be net zero, and emissions of carbon are priced into everything, a company can decide whether it’s more efficient to, say, retool my fleet to be electric, or keep my gas-powered fleet and pay for negative emissions credits.”

Wadhams feels similarly pragmatic about the moral niceties of ocean geoengineering to save the climate.
“The main word to use in relation to methane escaping from the Arctic is: ‘Help!’” he says.
For him, the overarching sense is that we are reaching the denouement of the action movie, and only have the final act left in which to save the planet.

“This is all very hard,” says UCLA’s Sant.
“But action is the need of the hour.”

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Sunday, June 27, 2021

Aquatic affection: How a scuba diver found a good friend under the sea

Scuba diver Hiroyuki Arakawa and Yoriko are the unlikeliest of friends.
While they both share a love for the sea, Yoriko's gills and tail make her a little more aquatically inclined. Nearly every day for the past 25 years, Arakawa has been diving into the waters of Hasama Underwater Park in Tateyama, Japan, to visit Yoriko—an Asian sheepshead wrasse.
One day, Arakawa found her looking exhausted and carrying an injury.
So he did what any friend would do: he took care of Yoriko, feeding her crabs and nursing her back to health.
Their decades-long friendship is proof there's no greater bond than the one between man and fish.
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