Meet the creepy critters of the Southern Ocean’s ‘twilight zone’


They are slimy, some of them are transparent and kind of creepy and you wouldn’t want to encounter one on an ocean swim, but luckily you never will.

These are the creatures of the Southern Ocean’s “twilight zone” — a 200- to 1,000-metre layer of water that lies just beyond the reach of light.

The researchers who collected them have just returned from a six-week trip on the CSIRO’s Investigator research ship.

But the trip was about a lot more than collecting the weird and wacky marine life.

“The voyage focused on creatures that are called micronekton, for example small fish and squid, crustaceans, and jellyfish,” said marine biologist Svenja Halfter.

“Micronekton undertake large vertical migrations through the water column: they swim up to the surface at night to feed and migrate further down during the day to avoid being seen by predators.

Marine biologist Caroline Sutton says these gelatinous plankton, known as siphonophores, are some of the fastest growing organisms.(Supplied: Svenja Halfter)

The voyage, known as the Southern Ocean Large Area Carbon Export (SOLACE), features contributions from CSIRO, the University of Tasmania’s Institute for Marine and Antarctic Studies, Australian National University, Curtin University and the Australian Antarctic Program Partnership (AAPP).

The 20 researchers on board have completed what they say is the most extensive study of the Southern Ocean of its kind, and they are hoping it will help them understand how the ocean stores carbon.

“The ocean plays a role in the global carbon cycle that is every bit as important as the forests on land,” said voyage chief scientist Phillip Boyd.

He said the “driving force” were the billions of tiny plankton that capture carbon from the atmosphere through photosynthesis, much like plants.

When these organisms die or are consumed by the creatures that migrate to the upper levels of the ocean, the waste forms something known as a marine snowfall.

“It looks like a snow shake [globe]. You have this material sinking down [to the sea floor] and that’s taking carbon out of circulation for centuries or longer,” he said.

Coloured flat worms that live deep in the ocean.
Pelagic worms were also uncovered from the ocean’s “twilight zone”.(Supplied: Svenja Halfter)

So where do the creepy critters come in?

“We call this the active carbon pump because it injects carbon into the deep sea, where bacterial recycling rates are slower than at the surface,” said Ms Halfter.

Marine biologist Caroline Sutton said they want to know “who’s there, where they are, how they’re moving and who is eating who”.

“We can take a tissue sample and work out where they’re eating,” she said.

Marine biologist Caroline Sutton stands in front of the RV Investigator in Hobart.
Marine biologist Caroline Sutton stands in front of the RV Investigator in Hobart.(ABC News: Lucy MacDonald)

“If they’re eating zooplankton and then moving down then they’re taking that [carbon] with them.

She said scientists will also try and work out how much carbon the creatures store.

“What we’ll do is get the samples, dry them up and burn them up and work out how much energy they’ll give off and that’s how much carbon they’ve got stored in them,” she said.

Ms Sutton said the most abundant animals in their samples were the gelatinous ones.

The question the scientists are also asking is how climate change could affect the ocean’s ability to store carbon.

“As the ocean warms, it actually changes how productive it is, it changes the amount of marine snow going into the deep ocean so it may actually alter some of those processes significantly,” Professor Boyd said.

“It’s more difficult for the plant nutrients that are plentiful in the deep ocean to come to the surface so it may slow up the growth of the plankton and slow down the amount of snow sinking into the deep ocean.”

Thank you for dropping in and seeing this news update involving National and Tasmanian News and updates named “Meet the creepy critters of the Southern Ocean’s ‘twilight zone'”. This news article was presented by My Local Pages as part of our Australian news services.

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Escalating Ocean Heat Might Affect Future Ecosystems

ecosystems

In a recent study published in Scientific Reports, it records that baby sharks will find it difficult to survive on the Great Barrier Reef, at least by the end of the century. This surfaced as climate change and warmer oceans led the creatures to be born smaller, exhausted and undernourished.

The latest study from James Cook University’s (JCU) ARC Centre of Excellence for Coral Reef Studies has put the focus on epaulette sharks, which is an egg-laying shark found only on the Great Barrier Reef.

According to the study co-author Jodie Rummer, the epaulette shark was a species that was “really tolerant” even to very challenging and changing conditions, including ocean acidification.

“We started investigating the effects of rising temperatures … and what’s particularly alarming is that temperatures seem to be its kryptonite. Warmer temperatures are really having a negative effect on at least the early development of this particular shark species.” Dr Rummer said.

Along with the JCU team, Dr Rummer, including lead author and PhD candidate Carolyn Wheeler, extensively studied the shark eggs and hatchlings in controlled environments, simulating current reef temperatures and predictions for the middle and the end of the century.

And as per the doctor, temperatures were expected to rise from 2 to 4.5 degrees Celsius by 2100.

Dr Rummer added, “We could control conditions tightly in the laboratory and isolate the effects we were seeing and associate them just with that elevated temperature effect.”

Meanwhile, Ms Wheeler said researchers found the warmer the conditions the faster the embryos developed. “The embryos grew faster and used their yolk sac quicker, which is their only source of food as they develop in the egg cast. This led to them hatching earlier than usual. This meant hatchlings were not only smaller, they needed to feed almost straight away — while lacking significant energy.”

This was a concern for the future of all species of sharks.

As what Dr Rummer asserted “If this shark is having trouble coping with ocean warming conditions, that’s going to be a really big problem for other shark species that are less tolerant and not as robust to changes in their environment.”

Thus, should one species in an ecosystem be impacted; it could cause effects for the flow-on to an entire ecosystem’s health. This emphasizes that our future ecosystems hugely rely on taking urgent actions to mitigate climate change.

Dr Rummer even cited that if ocean warming did not stop, sharks would have to find new cooler habitats to live in or adapt over generations.

“But sharks are at a particular disadvantage for adaption as they can’t change their DNA over generations fast enough to keep up with the changing planet.”

(Image source: ABC News)

Oceans protect circumbinary planets | Science


Planets orbiting binary stars, like the system in this artist rendering, are more likely to be habitable if they have Earth-like oceans.

IMAGE: NASA/JPL-CALTECH

Exoplanets that orbit a binary star, known as circumbinary planets, can experience large variations in stellar heating over less than the planet’s orbital period. Wolf et al. performed three-dimensional simulations of how Earth’s climate would differ if it orbited in the habitable zone around a Sun-like star with a smaller stellar companion. Even in extreme cases, they found that Earth’s oceans provided enough thermal inertia and negative feedback through cloud formation to buffer the planet against catastrophic climate variations. However, temperatures on land can experience complex additional season-like variations. The authors conclude that circumbinary exoplanets can remain habitable if they have Earth-like oceans.

J. Geophys. Res. Planets 10.1029/2020JE006576 (2020).



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Our Oceans Are Going ‘Nuclear’ Because of Climate Change


Math can be scary, but if you’re in the market for some really terrifying mathematics, a major new study puts hard numbers to the rate at which oceans are heating up due to global warming. Hold on to your exponential functions.

According to research published this week in the journal Proceedings of the National Academy of Sciences, the world’s oceans are absorbing around 90 percent of the excess energy caused by greenhouse gas emissions. That’s to say that the bulk of global warming is sinking into the world’s oceans, increasing temperatures and triggering sea level rise worldwide.

The compiled estimates suggest that global warming of the oceans from 1871 to the present adds up to about 436 x 1021 Joules. Unless you speak math, that might not mean much, so researchers have provided some context. The excess heat absorbed by the oceans in that time frame is around 1,000 times the annual energy use of the entire population of Earth.

For a more vivid analogy, the science team at The Guardian crunched the numbers with a different metric in mind. Global warming, it concluded, has heated the oceans by the equivalent of one atomic bomb explosion per second for the past 150 years.

RELATED: Will Nuclear Fusion Energy Arrive in Time to Mitigate Climate Change?

Bracing analogy, isn’t it? The Guardian editors checked their calculations with the lead author of the study, Laure Zanna of the University of Oxford, and got no argument from the veteran climate physicist. 

“I try not to make this type of calculation, simply because I find it worrisome,” Zanna told The Guardian. “We usually try to compare the heating to [human] energy use, to make it less scary.”

Hoo boy.

These new estimates support evidence that the oceans are absorbing most of the excess energy in the climate system.

Compiled by an international group of scientists, the new study employed techniques from an array of disciplines, including physics, mathematics, earth science, and climatology. The basic approach was to take the combined worldwide measurements of ocean temperatures since 1871, then run that data through the latest computer models of ocean circulation patterns to find where all the heat has gone.

Developed by researcher Samar Khatiwala, the technique uses blunt force mathematics to assess global ocean warming down to the seabed.

“Our approach is akin to ‘painting’ different bits of the ocean surface with dyes of different colors and monitoring how they spread into the interior over time,” Khatiwala said in a statement issued with the new research. “If we know what the sea surface temperature anomaly was in 1870 in the North Atlantic Ocean we can figure out how much it contributes to the warming in, say, the deep Indian Ocean in 2018.”

RELATED: How to Harness the Oceans to Save the World From Climate Change

The distressing upshot is that, according to the research team, these new estimates support evidence that the oceans are absorbing most of the excess energy in the climate system, which is produced from greenhouse gases emitted by human activities.

The really important part, for those of us who live in threatened coastal areas, is that warmer oceans mean rising sea levels that are compounded by the physical expansion of water as it gets warmer. In other words, those melting ice caps are only part of the problem.

The new research should help scientists make more accurate predictions in the years to come of where and when sea levels will rise. Presumably, this will be useful to us survivors paddling around in the floating city of New Topeka.



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Paul Kelly, Lucky Oceans collaborate with Indigenous Roebourne, Broome artists on Songs for Peace


Major Australian artists, including Paul Kelly, came together over the weekend with many Indigenous Roebourne and Broome musicians to celebrate the International Day of Peace and the life of John Pat.

John Pat died in police custody in Roebourne in 1983 at the age of 16.

His death was one of a number of Aboriginal deaths in custody that sparked the Royal Commission into Aboriginal Deaths in Custody.

Paul Kelly, Lucky Oceans, David Hyams, Vicki Thorn of WAIFS fame and many Indigenous Roebourne and Broome musicians performed a Songs for Peace concert, at the town’s Ngurin amphitheatre.

After weeks of collaborative song writing workshops in the community, driven by arts and social change agent Big hART, the songs written have been performed and will eventually be recorded professionally on a new album — the third in their Songs for Peace series.

In his own recording studio in Roebourne, Angus Smith said the collaborative music process writing was like a counselling session.

“Our old people said we need to express ourselves with talking or singing,” said Mr Smith, referring to the Ngarluma and Yindjibarndi elders of the Pilbara.

“Our elders kept our history alive through music.

“We’re doing the same thing, but the difference is some of it is in language, some of it is in English.”

A ‘pure process of songwriting’

David Hyams, Michelle Adams, Allery Sandy, Jean Churnside, Patrick Churnside and Lucky Oceans rehearsing for the Songs for Peace concert.(Supplied: Claire Leach/Big hART)

Allery Sandy wrote song titled We’re Still Here, in reference to all the people who have gone or passed away in the town that has seen much sorrow over the years, but now appears to be in a healing phase.

Remembering John Pat formed a large part of these celebrations.

Artists sat around the John Pat memorial fire pit, sharing roasted kangaroo tails each afternoon during the songwriting workshops.

A group singing with a guitarist.
Lucky Oceans leads a songwriting workshop in Roebourne.(Supplied: Claire Leach/Big hART)

Lucky Oceans said Roebourne residents have changed his whole way of working.

“We’re not talking about a song that tries to be a hit on the radio, it’s the pure process of songwriting and it’s really inspiring.”

‘I sing to heal’

A woman of the stolen generation, Lois Olney calls Roebourne her first home.

A woman singing and a man playing music.
Lois Olney and Lucky Oceans performing at the third Songs for Peace concert in Roebourne.(ABC Pilbara: Susan Standen)

The well-known singer has had a long career in the jazz world of Perth and has written songs about her father and two brothers who were lost to her in custody.

She has written songs for her Indigenous sisters and collaborated on an album ‘Red Earth Blue Sky’ with Lucky Oceans, who is her mentor.

But Olney’s sense of humour shines in the song Dream On, written while watching the cricket in a match between Australia and Sri Lanka.

‘Sense of pride’ performing

Ngarluma man, Tyson Mowarin, has written the song Ngaarda Ngurra about his country.

He said everyone that comes to the workshops contributes to a collaborative song in some way and the concerts brings a good feeling to the community.

“There’s always a sense of pride; it’s a big day to sing all those songs to a live audience,” Mowarin said.

people sitting with guitars
Tyson Mowarin, Rachel Mason, Allery Sandy, Naomi Pigram, Tehya Jamieson writing songs at the Big hART space in Roebourne.(Supplied: Claire Leach/Big hART)

Other songs performed included When Will I Ever Get Outta Here? written by prisoners inside the notoriously hot Roebourne Prison in collaboration with David Hyams culminating in the album Murru.

A new song, In My Dreams, by Tootsie Daniels who lost her daughter to suicide, was performed by Paul Kelly on a video hookup from his Melbourne garage where he is in lock down during COVID-19.

Two men singing and playing music.
Musician John Bennett with the Songs for Peace concert musical director Lucky Oceans in Roebourne.(ABC Pilbara: Susan Standen)



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