Saturday, January 29, 2022

Bigfin squid

It’s not every dive that deep-sea explorers encounter a bigfin squid (Magnapinna sp.).
It’s actually pretty unusual; roughly a dozen sightings have been confirmed worldwide.
So, when we captured an adult bigfin squid on camera during Dive 10 of Windows to the Deep 2021 off the West Florida Escarpment in the Gulf of Mexico, it was quite an exciting moment.

Friday, January 28, 2022

Canada (CHS) layer update in the GeoGarage platform

83 nautical raster charts updated & 2 new charts added

‘If I don’t end up in intensive care, it’s a bonus’: the beauty and pain of being the world’s best endurance swimmer

Chloë McCardel on Bondi beach.
The Australian ultra-marathon swimmer completed her record-breaking 44th crossing of the English Channel in October.
Photograph: Carly Earl/The Guardian

From The Guardian by Stéphanie Wood

From jellyfish in the Caribbean to hypothermia in the English Channel, swimming hasn’t been easy for Chloë McCardel – but can feel ‘so wild and free’

Chloë McCardel and I are going for an ocean swim at Bondi.
She dives into the foamy sea ahead of me – more slender mermaid than broad-shouldered Amazonian.
Knee deep, I feel the current suck at my flesh.
It’s not one of Bondi’s better days.
Chest deep, I realise I’m being dragged out and my very amateur ocean-swimming abilities are no match for this surf.
Panic rises.
McCardel is an impatient white-cap in the distance.
What was I thinking, suggesting a swim with superwoman?

By any objective measure, Chloë McCardel is also a crazy woman, her commitment to putting herself through demented levels of physical and mental torture almost inexplicable.
“I own crazy, I wear it as a badge of pride,” she tells me later.

Stephanie Wood prepares to swim out into the Bondi surf with Chloë McCardel.
Photograph: Carly Earl/The Guardian

On 13 October, the 36-year-old Melbourne-born, Sydney-based ultra-marathon swimmer set a new world record, completing her 44th crossing of the English Channel in 10 hours and one minute.
She left the water, stood on a French rock at Pointe de la Courte Dune and raised her lanolin-smeared arms in victory.
McCardel’s 44 crossings of the world’s busiest shipping highway include three non-stop doubles (to France and back) and one triple non-stop (to France, back to England, then to France again).
The “King of the Channel”, Englishman Kevin Murphy, has done only 34 crossings.

McCardel has conquered other waters too: in 2014 she set a world record for the world’s longest non-stop ocean swim – 124.4km from Eleuthera Island in the Bahamas to the capital Nassau, a 41-hour, 21-minute journey.

McCardel finishing her record-breaking English Channel swim.Photograph: Gareth Fuller/PA

But the bare numbers and facts hardly tell McCardel’s story.
There are good times when the sea is as smooth as a pane of glass, the water clarity is extraordinary, dolphins bounce around and she feels her technique is exquisite.
But things can go bad quickly.
In 2013 she jumped into the sea in Havana, Cuba, to attempt to be the first person to swim the 166km to the Florida Keys without a shark cage.

After about 10 hours of heavenly swimming, with 40 or 50 hours ahead of her, and dusk setting in, McCardel started seeing translucent shapes many metres below her.
“I’m like, ‘Oh, that’s interesting,’ and then literally like 10 minutes later, it was like a blanket underneath me just rising up and I’m like, ‘Oh this is not going to turn out well.’” 
She was stung dozens of times by what is believed to have been a jellyfish similar to a box or irukandji.

Almost immediately, her right arm was paralysed and she could no longer use it to stroke.
She called to her support team to get her out but they did not realise the extent of the problem and shouted affirmations – keep going, you can do it.
In a marathon swim you never get out.
The jellyfish were still rising.
McCardel curled into a ball to reduce the surface area of her body.
“Once my head went under the water, they were like: ‘We need to get her out.’”

Twenty minutes or so after the first sting, she was hauled out of the water on to the boat.
“I was whimpering, I was making a dying animal noise and they were picking the jellyfish stings off me.
One person even pulled one out of my mouth like a bit of spaghetti.
I just wanted to die – the pain was horrific.”

So many other stories: the first time she attempted the Channel in 2009, she signed up for a double crossing and the captain of the support boat lost her for a time during a dark and stormy night when she was two-thirds of the way back to English shores.
“They drifted away and I was screaming out ‘Don’t leave me behind’ – I was terrified.”
She was battling two-metre waves and felt the ghostly presence of hulking ships which take a kilometre to come to a stop.

McCardel looks out over Bondi.
In cooler water swims, she has been told, she had been on the edge of death.
Photograph: Carly Earl/The Guardian

During her first attempt to triple-cross the Channel in 2011, the weather turned.
She was floundering, barely stroking with one arm and resisted her support crew’s attempts to get her out.
“My brain was not functioning.” When she was pulled out she couldn’t walk, was delirious and mumbling and dangerously hypothermic.
In intensive care at Canterbury Hospital, a doctor told her that 30 more minutes in the water and she would have been dead.

There are clues in McCardel’s childhood to the woman she would become.
Her role models – three older and sporty siblings – told her she could only play with them if she kept up.
“I wanted to be better at whatever game they were playing or I wanted to be like them and so I would push myself.” When she was about seven, she insisted on pedalling with her 14-year-old brother on his paper round.
He told her she couldn’t because she wouldn’t keep up.
“I’m like, ‘No, I will keep up, I’m coming.’”

Her parents were far from pushy and when she started to swim competitively as a teenager, they refused to take her to swim training at 5am (they agreed to pick her up afterwards).
On weekdays, a friend’s mother took her and on weekends she set her alarm for 3.15am and rode her bike 9km.
She remembers the day her mother came outside in a pink nightie and, unsuccessfully, tried to stop her pedalling off in the dark.
McCardel feared she’d be in trouble when she got home.
“Instead, my Dad’s like, ‘Right, we’re going to buy you some lights.’”

But McCardel’s times weren’t fast enough to get her into the national championships in the open category and her parents encouraged her to quit swimming to concentrate on her final two years of study.
After school, she went to Monash University to do an arts degree.

‘I had this beautiful connection with the water,’ says McCardel.
Photograph: Carly Earl/The Guardian

At some point, though, she had decided she wanted to be “the best in the world at something”.
She tried triathlon but failed to reach an elite level.
She did well in the Melbourne marathon and started to think that distance might be where she could be the best.
In 2007, she did a marathon swim, 11.3km between Frankston and Mornington.
“It was so wild and free … I had this beautiful connection with the water.” About midway through the swim she was smashing the field – the first woman, with only one man ahead of her.
“I just knew at that moment that I could be the best in the world at marathon swimming.”
She came second, after the male swimmer.

Chloë McCardel’s swimming career has not made her money.
Most of her income comes from coaching others to swim the Channel and motivational speaking.
(As a survivor of domestic violence, she also advocates for the criminalisation of coercive control.) Ahead of every swim, she runs fundraisers.
But the goal is the thing that pulls her forward: “I set scary goals and then I’m so petrified I get out of bed in the morning.”

She has set herself another scary goal: in 2022 she wants to be the first person in history to swim the 92km from England to Belgium through the stormy, frigid waters of the North Sea.
“The idea is to get to the other end before I die.
And if I don’t end up in intensive care, it’s a bonus.”

The Bondi surf that is making me panicky is like a soak in a bath for McCardel.
She strokes back towards me and, with no small amount of embarrassment, I tell her that I think we should grab a coffee instead.
No dramas, she says as we reach the sand.
As we towel off, she adds: “I don’t even like waves.”

Links :

Thursday, January 27, 2022

ECMWF makes wide range of data openly available

ECMWF have just added more than 50 new products to its #OpenCharts catalogue!
These forecast charts are free for anyone to access, redistribute and adapt - even for commercial applications - part of our open data Strategy for 2021-2030. 


From 25 January 2022, a wide range of ECMWF’s forecast data across the globe will be openly available.
This move towards ‘open data’ comes after a large range of forecast charts were earlier made available to anybody interested in them.

The data that are becoming available are based on a range of high-resolution forecasts (HRES – 9 km horizontal resolution) and ensemble forecasts (ENS – 18 km horizontal resolution).
They will be made accessible at a resolution of 0.4 x 0.4 degrees.

While many programming languages can be used to access and visualise the data, ECMWF has prepared a set of Jupyter notebooks to help users familiar with Python and Jupyter discover the open dataset.
They can also reproduce the plots from our open forecast charts using our open-source software libraries.

An overview of what kinds of data are available is given on the ECMWF website. More detailed explanations of how to access the data are also available.
The plan is to expand open data in the future by adding more data.

The data are available through ECMWF’s https service and via the Microsoft Azure cloud. In future, they may also be made available via other cloud providers.

Use of the data is governed by the Creative Commons CC-4.0-BY licence and the ECMWF Terms of Use.
This means that the data may be redistributed and used commercially, subject to appropriate attribution.

Jupyter notebooks for reproducing open chart plots using open data can be accessed via the top right-hand menu of the available plots.

ECMWF looks forward to user feedback, which will help the open data provision to evolve.


Consequence with Weather4D R&N mobile app  

New release of Weather 4D R&N available on the App Store (2.0.77).
Added ECMWF model at 0.4° (Runs 00Z and 12Z)
with currently wind at 10m and msl pressure.


Where's the catch? The fishery surveys keeping our seas sustainable

Fish sampling on the research vessel Celtic Explorer, operated by the Marine Institute (Ireland) - Copyright Photo by Denis Loctier/Euronews

From Euronews by Denis Loctier

For six weeks every year, the research vessel Celtic Explorer surveys Ireland‘s Atlantic shelf, sampling 170 points on the nautical chart.

Led by David Stokes, the Marine Institute scientific team tackles questions only fisheries surveys can answer: how many young fish have been spawned here over the past year?
Is this new generation of fish numerous enough to replace what has been removed from the sea by fishing vessels? In other words: is commercial fishing here sustainable?

The Chief Scientist of the Irish Groundfish Survey 2021, David says: "We're out at this time of the year, basically fishing to try and assess the size of the various fish stocks and all the demersal species - these are the species that live and feed on the seabed, basically. So we try and estimate whether the stocks are going up or down and particularly try and focus on the juvenile fish that are coming through into the fishery."

Marine Institute scientist David Stokes leads the Irish Groundfish Survey.© Euronews

'Good science'

At each sampling station, the vessel deploys a trawl that has been specially modified to catch small fish. This is different from commercial fishing vessels that use nets with large meshes, aimed at targeting only mature fish that hopefully have already spawned offspring.

For the scientists, this work is vital for forecasting what catches can be expected in the future.
Their motto is “Good science supporting sustainable fisheries”.

"We shoot the trawl, it goes to the seabed, and then we tow it along the seabed for 30 minutes. Haul it back. And then it's dropped into the hopper, and then the fish come into the fish room, where everything is sorted into species," David explains.
David Stokes explains how the surveys provide a unique insight into fish populations - including some key facts that cannot be found in the commercial catch statistics.

An onboard laboratory works like a busy factory floor in the middle of the sea: researchers quickly sort fish from the moving conveyor belt into separate boxes.

They are especially interested in the commercial stocks like haddock, whiting and other economically important species.
Each fish is then measured with an electronic measuring board. All the data are combined in a database to make it easy to spot any errors.

"For commercial stocks we take length, sex, maturity and the otoliths (ear-stones) from the head, which gives us the age of the fish. It's kind of like reading the age of a tree by the rings," explains Sinead O’Brien, a Lab Analyst at the Marine Institute.

Researchers sort and measure fish in a lab onboard the Celtic Explorer. They are particularly interested in commercial fishing stocks, such as cod and haddock.© Euronews

Monitoring the marine ecosystem

By studying ear bones, scientists can accurately determine the proportion of young fish in the population.
Shrimp, crab and invertebrates also help monitor the general health of the marine ecosystem.

"You see here in the tray, we've got a really good selection of benthic creatures that we caught on the last tow. It tells us how diverse the community of animals are at that particular station at that particular time. So we know that in this area, we're seeing a certain number of species every year and we're always interested in species' richness and diversity," says Jennifer Doyle, a Fishery Scientist at the Marine Institute.

Everything trapped in the trawl is logged - even plastic litter.
Fishery surveys collect a wide range of data used by marine scientists - such as the water temperature, the salinity at various depths or the hydroacoustic profile of the seafloor.

As part of the EU Data Collection Framework (DCF), this is one of many coordinated surveys along the northern and western coasts of the European continent.

"These surveys are run around the same time every year, normally around October to November, and include probably about ten countries, all using the same standard protocols, procedures and very similar sampling gear, even though it wouldn't be exactly the same," explains David.
"It is quite a piece of work to try and keep independent countries with different languages, different capacities and different resources, to keep everybody on the same fixed page, you know, all the time. So yeah, there's quite a lot of coordination work that has to go into actually keeping all that as standard as it is," he adds.

Managing fishing stocks

The results of the surveys conducted by all these research vessels are collected and analysed at an intergovernmental organisation, headquartered in the Danish capital.

The International Council for the Exploration of the Sea (ICES) in Copenhagen examines scientific and commercial data and forecasts future changes in marine ecosystems - preparing what’s known as scientific advice for the decision-makers charged with managing fisheries.

"All the countries submit their data on surveys and also on catch here to ICES. And then that flows into what we call working groups, which are international scientific groups, which put it all together and start putting the information into our models," explains Mark Dickey-Collas, the Chair of the Advisory Committee to the International Council for the Exploration of the Sea.

Based on the advice of such scientific bodies, the EU and its neighbours can restrict fishing to help populations recover - or expand quotas for those species that are thriving.
Given the competing interests, reaching agreement is not easy.

"There are some major challenges. One is trying to make sure that we work in partnership with the fishing industry and also with the environmental groups to make sure that the overall impression and understanding of the processes are good enough to have a consensus in terms of our advice," says Dickey-Collas.

Danish fishermen say they are happy to share their own data with scientists.
They say some quotas are putting their businesses at risk.
© Euronews

Finding the right balance

While environmental activists see many catch limits as excessive and unsustainable, fishermen say tight quotas put their businesses at risk.

At the port of Thyborøn in North-Western Denmark, fishermen are sceptical about the scientific advice: they say the catches are better than forecast, but the available resources can’t be fully harnessed due to what they see as a rush towards sustainability.

"Stocks go up and down. We, as fishermen, have to live with that. But what's really important is that the advice is what we see at sea, and at the moment sometimes there's a big difference. You have climate change, you have cod stocks move north - maybe it's time to modernise the way they do the surveys!" says Alfred Fisker Hansen, the Chairman of Thyborøn Harbour Fishermen Association.

Fishing quotas are a matter of much debate, but there’s no arguing that marine resources must be managed wisely.

The fishermen say they are happy to share their own data with the scientists - and new technologies make that easier.
The Thyborøn fishing auction sells around 150 tonnes of fish per day - all online. That's valuable data readily available for researchers.

In addition to that, fishermen often invite scientists onto their vessels to make observations that can help fine-tune mathematical models.

"We have good cooperation, in Denmark at least, between scientific institutions and the fishing industry," says Michael Andersen, Chief Scientific Advisor to the Danish Fishermen Association.

"There may be some harsh words sometimes and disagreements, certainly, quite often, but there is a good cooperation. It's a common goal of getting the stock size right, because that's in everybody's interest. Everybody appreciates that," he adds.

The fishing industry relies on healthy fishing stocks for its very survival. However imperfect, scientific assessment still remains the best way to monitor them.
Links :

Wednesday, January 26, 2022

Ocean Mapping: a history of exploration in meaningful words

The current bathymetric map of the world’s ocean floor.
The coloured areas show mapped areas, whereas the black parts show the massive areas that still have to be mapped.
(Courtesy: The Nippon Foundation-GEBCO Seabed 2030 Project).
From Hydro by Alex Bastos and Pedro Menandro

The Evolution of Capturing the Seabed

Over the last few centuries, mapping the ocean seabed has formed a major challenge for marine geoscientists. Ocean bathymetric charts and submarine geomorphology have significantly impacted our understanding of our planet, from plate tectonics to deep-sea ecosystems. The history of ocean mapping can be viewed through scientific trends based on words used in the scientific literature. To this end, data mining was carried out on 454 papers dated between the 1930s and 2019 using the keyword ‘seabed mapping’.

The first bathymetric maps were based on ‘lead line’ (plumb) measurements.
In 1855, a first bathymetric profile of the Atlantic Ocean was shown in a textbook published by Matthew Fontaine Maury.
From 1873 to 1876, the HMS Challenger expedition collected more than 500 plumb measurements, revealing the depth of the Mariana Trench and a more comprehensive map of the Atlantic Ocean, with the Dolphin, Connecting and Challenge Ridges, known today as the Mid-Atlantic Ridge.
Bathymetric charts became an important asset worldwide and, in 1903, Prince Albert I of Monaco launched the first General Bathymetric Charts of the Ocean (GEBCO).

The beginning of the 20th century was marked by a change in the seabed mapping approach.
The development of acoustic technology introduced the use of echosounders, allowing the collection of much more data in much less time.
After World War II, with its extensive use of echosounders, Maurice Ewing, Bruce Heezen and Marie Tharp produced a series of bathymetric maps revealing the physiographic features of the ocean floor, published in a seminal Special Paper of the Geological Society of America (1959).
The ocean floor morphology provided key information to fill in the plate tectonics puzzle, and also supported Wegener’s hypothesis of continental drift. In 1977, the global seabed map produced by Heezen and Tharp and painted by the artist Tanguy de Rémur, The Floor of the Oceans, became a milestone in seafloor mapping and physiography.

The continuous development of acoustic technology brought a novelty to seabed mapping: the revolutionary multibeam bathymetry system.
The first non-military multibeam system was used in 1977 during the Jean Charcot Expedition (Seabeam and Hydrochart).
In the past decades, we have witnessed the striking technological development of acoustic and non-acoustic seabed mapping techniques and systems.

Temporal Evolution

The lexical analysis of scientific literature pinpoints the state-of-the-art evolution in seabed mapping over almost a century.
Not only was a growth in scientific production observed, but also a clear trend in the use of scientific, technological and methodological terms.
In general, the literature began with exploratory investigations (‘ocean’, ‘interpretation’, ‘investigation’), shifted to the importance of technology in scientific results (echo, side scan, multibeam), and recently turned toward applications of ocean mapping, as terms such as habitat mapping, seabed classification and backscatter became more common.
The widespread use of the word ‘datum’ over the last decades is also consistent with an increase in data availability and quality.
Illustrative scheme summarizing the most frequent words by decade.
(Image source: Menandro & Bastos, 2020)

Over the entire timeframe, it is clear that scientific publications related to seabed mapping have followed investment trends in research, science and technology, but also reflect national and multinational concerns.
In the past two decades, the demand for the definition of exclusive economic zones, support for marine spatial planning programmes, use of the seabed for renewable energy (e.g. offshore wind farms) and the returned interest in deep-sea mining have shaped part of the scientific publications.

Another interesting aspect of the lexical analysis is the increase in publications related to shallow waters (water depth < 200m) in the past two decades.
This may reflect shifting priorities toward coastal and shelf mapping, or that research groups and academics have concentrated their efforts in shallower water mapping.
Of course, deep-sea mapping is much more expensive and requires a more robust infrastructure, so access to suitable technologies for deep-water studies is more limited.
However, looking ahead, and considering new technologies, the use of autonomous underwater vehicles is still novel, so we can expect an increase in scientific publications related to high-resolution deep-sea mapping.
Word cloud composition for each year in the last decade. (Image source: Menandro & Bastos, 2020)

Concentrating the analysis on the last decade, the term ‘backscatter’ has become almost as popular as seabed mapping.
Terms like ‘classification’ have also become widely used in publications.
This represents the effort being made to develop seabed classification schemes, tools and approaches. Seabed mapping as applied to habitat mapping has significantly increased in scientific publications during the last decades.
One of the main demands in habitat mapping is seabed classification, using supervised and non-supervised, and automatic and semi-automatic approaches.
The demand for classification and accuracy can be seen in the increase in terms such as ‘accuracy’ (2016, 2017, 2018 and 2019), ‘repeatable’ (2017, 2018 and 2019), ‘multispectral’ (2017, 2018 and 2019) and ‘machine learning’ (2018 and 2019).
Once again, technological developments and new data analysis tools are driving scientific publication. 

Importance and Future Directions of Seabed Mapping

The last century has seen an impressive development in ocean mapping technology and efforts. Technology, innovation and data analysis are changing faster than ever, and ocean mapping is also following this trend.
The United Nations’ declaration of the Decade of Ocean Science for Sustainable Development (2021–2030) states that a map of the ocean (digital atlas) is a research and technology development priority area (R&D Priority Area 1).
From 2017 to 2021, Seabed 2030, an international effort led by the Nippon Foundation with the support of IOC, IHO, GEBCO and several other partners, was able to increase the percentage of mapped ocean floor from 7% to almost 20%. The target is to have the entire seafloor mapped by 2030.

All these challenges and efforts highlight the importance of ocean/seabed mapping.
A bathymetric chart, a seabed morphology/physiographic map or a classified seabed is needed for all kinds of applications, including hydrography, marine geohazards, mineral resource exploration, renewable energy, marine spatial planning, exclusive economic zone definition, technological research and development, fishery resources management, environmental impact studies and climate change models.
All of the social targets of the UN Decade of Ocean Sciences also require seabed mapping.

Following the trends observed in the lexical analysis, the evolution of seabed mapping will probably consist of increasingly integrated investigations using new technology for data acquisition (AUVs, multibeam, multispectral multibeams, Lidar, underwater drones), sophisticated classification tools (unsupervised approaches, machine and deep learning, convolution neural network), and possibly new features and geographical analysis.
As the seabed is mapped, we will learn more about our ocean morphology.
The Five Deeps Expedition and the Northern Depths and Ice Age Geology of the Great Barrier Reef Expeditions are good examples of new ocean floor data revealing unknown features or mapping the real depth for the first time.

Exploration during the next decade will therefore have a profound impact on our knowledge of the oceans.
This will enable us to discover new marine landscapes, predict seabed habitats (mainly deep-sea habitats) for better resource management, improve circulation and climate models, and hopefully make the data available for everyone.
The effort to achieve the sustainable development of the oceans demands ocean mapping, and the scientific publications on seabed mapping will register the new findings and developments achieved during this decade.
By 2030, our knowledge of the ocean seafloor will have developed significantly, as happened with the seminal work The Floor of the Oceans by Bruce Heezen and Marie Tharp.
This will impact not only the marine geosciences but the entire marine sciences.
 Detail of the North Atlantic Ocean floor map by Bruce Heezen and Marie Tharp, painted by the Austrian painter and cartographer Heinrich C. Berann (Courtesy: US Library of Congress, Geography and Map Division).

Links :

Tuesday, January 25, 2022

Over 100 different species made this 2,200-year-old shipwreck home, study finds

The ship's ram as it was found on the seabed off Sicily at a depth of nearly 90 m, covered in marine life.
K. Egorov/SDSS-GUE
From Ars Technica by Jennifer Ouellette 
Ship's ram from First Punic War serves as "ecological memory" of 2 millennia of underwater life.

Shipwrecks hold an enduring fascination, both because of how they connect us to the past and because of the potentially priceless treasures that could be lurking within their sunken remains.
They are also invaluable resources for scientists interested in studying how marine ecosystems evolve and thrive, since sea creatures inevitably colonize the wreckage, transforming destruction into life. In fact, more than 100 distinct animal species were found living on a 2,200-year-old Mediterranean shipwreck, according to a recent paperpublished in the journal Frontiers in Marine Science.

"Shipwrecks are often studied to follow colonization by marine organisms, but few studies have focused on ships that sank more than a century ago," said co-author Sandra Ricci of Rome's Istituto Centrale per il Restauro (ICR).
"Here we study for the first time colonization of a wreck over a period of more than 2,000 years. We show that the ram has ended up hosting a community very similar to the surrounding habitat, due to 'ecological connectivity'—free movement by species—between it and the surroundings."

Rome and Carthage were archrivals in the mid-3rd century BCE who fought three wars. The first war began in 264 BCE on and around the island of Sicily, and it dragged on for 23 years.
Almost everything we know about the First Punic War comes from the writings of Greek historian-turned-Roman hostage Polybius, who wrote The Histories about a century after the First Punic War ended.
While there has been some debate about the accuracy of his accounts, most modern historians still rely heavily on Polybius, and his version of events is typically accepted when there are contradictions in other historical sources.

The war was ultimately decided at the Battle of the Aegates on March 10, 241 BCE.
By this time, the Romans had gone nearly bankrupt maintaining a years-long blockade against the Carthaginians.
They had to borrow the funds to build a fleet to extend their blockade to the last of the Carthaginian strongholds.
Although the Carthaginian fleet was larger, the Romans were better trained and emerged victorious.
The Carthaginians signed the Treaty of Lutatius, ceding control of Sicily to Rome and even paying reparations.

Enlarge / Close-up of the ship's ram and the marine animals on it.
Istituto Centrale per il Restauro (ICR)

Several artifacts believed to be from this battle have been recovered from off the coast of Western Sicily since 2010.
For instance, archaeologists have found 11 bronze rams from sunken warships.
These thrusting weapons were fitted to the bow of ancient galleys and designed to break through the hull framing of enemy ships.
Archaeologists have also found 10 bronze helmets and several hundred amphorae.
All the rams, seven of the helmets, and six complete amphorae have since been recovered (the rest are still on the seabed).
Based on inscriptions, archaeologists determined that four rams came from Roman ships, while one came from a Carthaginian ship—all most likely triremes, based on their dimensions.

The ship's ram that became a dream home for so many marine creatures was recovered in 2017. Because it has been on the ocean floor for more than 2,000 years, the ram had a long time to become part of a stable marine ecosystem.
"The ram has trapped mineral structures and fragments (i.e., tubes and shells) of species living in the surrounding habitats transported by bottom current," the authors wrote.
"Therefore, together with its inestimable value as an archaeological artifact, the ram... highlights the dynamics of biological colonization on a large spatial scale and serves as a relevant proxy for the study of marine biodiversity."

Dubbed Egadi 13, the ram was restored in 2019.
During that process, ICR scientists carefully sampled and documented all the sediment blocks and biological materials that had accumulated both inside and outside the hollow artifact.
The samples were carefully cleaned to remove sediment, dried, and sieved before being examined under a microscope.
Any biological fragmented remains were carefully preserved in Petri dishes for analysis.

Enlarge / Researchers sampling marine animals from the ship's bronze ram.
Istituto Centrale per il Restauro (ICR)

The researchers were able to identify 114 different invertebrate species that had made the 2,200-year-old ram their home, including 33 gastropod species, 25 species of bivalve mollusks, 33 species of polychaete worms, and 23 species of bryozoans.
They compared those findings to species found naturally in Mediterranean habitats in hopes of learning more about how the ram had been colonized.

"We deduce that the primary 'constructors' in this community are organisms such as polychaetes, bryozoans, and a few species of bivalves.
Their tubes, valves, and colonies attach themselves directly to the wreck's surface," said co-author Edoardo Casoli from Rome's Sapienza University. 
"Other species, especially bryozoans, act as 'binders': their colonies form bridges between the calcareous structures produced by the constructors. Then there are 'dwellers', which aren't attached but move freely between cavities in the superstructure. What we don't yet know exactly is the order in which these organisms colonize wrecks."

"Younger shipwrecks typically host a less diverse community than their environment, with mainly species with a long larval stage which can disperse far," said co-author Maria Flavia Gravina, a biologist with the University of Rome and the National Interuniversity Consortium for Marine Science.
"By comparison, our ram is much more representative of the natural habitat: it hosted a diverse community, including species with long and short larval stages, with sexual and asexual reproduction, and with sessile and motile adults, who live in colonies or solitary. We have thus shown that very old shipwrecks such as our ram can act as a novel kind of sampling tool for scientists, which effectively act as an 'ecological memory' of colonization."

DOI: Frontiers in Marine Science, 2021. 10.3389/fmars.2021.772499 (About DOIs).

Monday, January 24, 2022

Imray layers update in the GeoGarage platform

Surreal coral rose garden discovered off Tahiti

A “magical” coral reef stretching as far as the eye can see has been discovered off the coast of the South Pacific island Tahiti.
The beautiful reef took around 25 years to grow and was found in the "twilight zone", where it is highly unusual to unearth such a find as there is barely enough light to sustain life.
"It was magical to witness giant, beautiful rose corals which stretch for as far as the eye can see.
It was like a work of art," said French photographer Alexis Rosenfeld, who led the team of international divers that made the discovery.
The acres of giant corals in pristine condition show no sign of being damaged by climate change and demonstrate just how little we know about the ocean, according to experts.
They say it shows the need to protect the world’s remaining healthy reefs from environmental damage. 
From The Telegraph by Verity Newman
A “magical” coral reef stretching as far as the eye can see has been discovered off the coast of the South Pacific island Tahiti.

The beautiful reef took around 25 years to grow and was found in the "twilight zone", where it is highly unusual to unearth such a find as there is barely enough light to sustain life.

"It was magical to witness giant, beautiful rose corals which stretch for as far as the eye can see. It was like a work of art," said French photographer Alexis Rosenfeld, who led the team of international divers that made the discovery.

Corals shaped like roses in the waters off the coast of Tahiti
CREDIT: Alexis Rosenfeld/AP

The acres of giant corals in pristine condition show no sign of being damaged by climate change and demonstrate just how little we know about the ocean, according to experts.

They say it shows the need to protect the world’s remaining healthy reefs from environmental damage.
"For once, it's a positive story about coral reefs in the news, which is quite rare these days," Julian Barbiere, head of marine policy at UNESCO, said to CNN.

"The discovery suggests that there are, in fact, many more large reefs out in our ocean at depths of more than 30 meters, which have not been mapped," Mr Barbiere added.
"It's quite a puzzling finding."

The majority of the world’s currently discovered reefs are found in warmer waters in depths of up to 25 metres, according to Unesco.

But the reef near Tahiti, which spans almost two miles, was found nearly 70 metres underwater. Some of the rose-shaped corals measure more than 2 metres in diameter.

Climate change has resulted in coral bleaching, a stress response to overheating during bouts of warm weather in which they lose their colour and struggle to survive.

Perhaps the most famous - Australia's Great Barrier Reef, a World Heritage-listed wonder - has suffered severe bleaching to an estimated 80 per cent of its corals since 2016.
A researcher for the French National Centre for Scientific Research studies corals in the waters off the coast of Tahiti
CREDIT: AP/Alexis Rosenfeld

The discovery off Tahiti's shores suggests there may be many more unknown large reefs in our oceans, given that only about 20 per cent of the entire seabed is mapped, according to Unesco scientists.

"It also raises questions about how coral reefs become more resilient to climate change," Mr Barbiere said.

More of the ocean floor needs to be mapped to better safeguard marine biodiversity, according to Barbiere.

"We know more about the surface of the moon or the surface of Mars than the deeper part of the ocean."
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Sunday, January 23, 2022

Unsafe Passage: on board a refugee rescue ship racing for Europe

An overcrowded ship with asylum seekers leaves Libya bound for Europe – triggering a high-stakes showdown between a Doctors Without Borders vessel wanting to escort it to safety and the Libyan Coast Guard fighting to turn it back.
As the Libyans issue armed threats, tension grows below deck. With European countries' responsibilities toward refugees once again in the spotlight, here is an inside view of the desperate hope that is the deadly race for Europe. 

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