Marine Trackers Show How Warming Waters Affect Australian Sea Life And Beyond

ABC News - Rhiannon Shine

Acoustic signal receivers were installed in coastal waters around Australia for the massive study. (Supplied: IMOS/Fabrice Jaine)

New data mapping the movements of Australian marine life over the past decade will provide insight into how climate change might affect sea animal behaviour, researchers say.

The study by researchers at the Integrated Marine Observing System (IMOS) and Macquarie University has tracked the whereabouts of 117 marine species, ranging from sharks and saltwater crocodiles to sea turtles and jellyfish using sound-detecting underwater receivers.
The receivers pick up and record signals from acoustic tags that have been placed on fish and marine mammals.
Lead author Xavier Hoenner said the researchers collected and quality controlled 49.6 million acoustic detections from tagged animals.

Researchers are interested in how warming waters are affecting species like bull sharks. (Supplied: Jayne Jenkins )

"The established IMOS Animal Tracking Facility network, consisting of nearly 2,000 receiving stations located around the country, allowed us to track 3,777 Australian sea animals, including some of Australia's most iconic species," Dr Hoenner said.
IMOS Animal Tracking Facility leader Rob Harcourt said the data would help researchers to predict how animal behaviour might change in the future in response to warming waters.
"For example, in the case of bull sharks – a species we tracked that is known to be potentially dangerous – research has shown that they move within warmer waters, meaning it is important that we understand how they modify their movements in response to changes in ocean conditions and processes," Professor Harcourt said.
"We do have quite strong evidence that there are things like pulses of warm water that are coming down with the East Australian Current which is strengthening and has been strengthening over some time.
"With those water masses we find that fish are essentially staying in the same environment but that environment is actually moving.

"Over the course of the next few years we will be able to build some really complex models to allow us to predict what is going to happen as we understand more about the oceanography."

Marine life movements around Australia

Professor Harcourt said the tracking system showed some species travelled surprising distances.
"For instance, in Sydney Harbour the New South Wales government has been tagging bull sharks because of anxiety about people being bitten," he said.
"Our colleagues up in Townsville, which is about 2,400 kilometres away, also detected bull sharks and then discovered these were the same sharks that had been tagged in Sydney Harbour.
"We are now looking at their movements all the way up and down the coast over a number of years."
Some animals previously thought to be quite sedentary have also been proven to travel long distances.

The network of tracking devices consisted of nearly 2,000 receiving stations. (Supplied: IMOS)

"Sevengill sharks that are found in Tasmania have been detected over in South Australia," Professor Harcourt said.
"Sevengill sharks were thought to be quite restricted to really cold waters down here, and yet we know now that they go right up to South Australia, again, a couple of thousand kilometres away.
"That is potentially because of the way movements of water have changed."
Dr Hoenner said the tracking data was validated by a state of the art quality control algorithm developed in Hobart, which he expected to be used by other researchers around the world.
The algorithm identifies background noise signals and anomalous movements to strengthen the quality and re-usability of the data.
"There is a global need [for the quality control algorithm]," Dr Hoenner said.
"Everyone is spending a lot of time looking at the data and this could make the whole process a lot easier for everyone."
Professor Harcourt said the data, published in the nature journal Scientific Data, would help future investigations by other marine research groups.
"The data is available through the online Australian Ocean Data Network Portal, making it a very valuable resource for comparing the behaviour of marine animals today and in the future," he said.

Links

• Integrated Marine Observing System
• Integrated Marine Observing System Animal Tracking Facility
• Australian Ocean Data Network Portal
• East Australian Current
• Broadnose Sevengill Shark

Climate Change Projects Headline Innovation And Science Australia's 2030 Plan

AFR - David Marin-Guzman

Australia's chief scientist Dr Alan Finkel says the vocational educational and training system needs to be more responsive to changes in technology. Wayne Taylor

Restoring the Great Barrier Reef and de-carbonising the gas system have been pitched as "national mission" projects to inspire the next decade of innovation.
Innovation and Science Australia's 2030 strategy plan, to be released on Tuesday, proposes world-leading initiatives to raise the country's aspirations on what it can achieve akin to US President John F Kennedy's "moonshot" challenge.
According to the independent body's plan, the reef mission would restore and protect the reef from climate change, boosting scientific research while creating new products, start-ups and niche industries such as in bio-materials and 3D printers.
The Turnbull government's current Reef 2050 plan provided a "strong base" for the mission, the ISA said, but was primarily focused on direct threats to the reef such as the coral-eating crown-of-thorns starfish.
"It does not have an explicit climate adaptation strategy and is therefore insufficient to safeguard the reef beyond 2030."
Minister for Jobs and Innovation Michaelia Cash claimed the government has already moved to action the ISA's recommendation, by "committing last week to fund groundbreaking research to preserve the Great Barrier Reef".
However, the government's $60 million reef package focuses on targeting the crown-of-thorns starfish and land-based run-offs, with just $6 million spent on research and development for adaptation.

'Hydrogen City'
The ISA's other national mission candidate was converting an entire city to clean hydrogen gas by 2030.
Zero-emission energy sources such as solar, wind or hydro would be used to produce the hydrogen by splitting water into hydrogen and oxygen.
"This has never been done at the scale contemplated in this mission," the report said.
The technology improvements resulting from the large-scale deployment of hydrogen technologies would then create export opportunities and make Australia a leader in the field.
Public and private sectors would fund both projects at an estimated $500,000 over 10 years.
But the ISA's most "ideal" national mission would be to integrate DNA studies and precision medicine into the healthcare system.
The medicine mission would allow for early diagnosis and prevention of diseases, making Australia "the healthiest nation on earth".
The ISA said Australia was already "well connected" to international efforts in the area and the mission would build on the government's medical research future fund and $500 million already committed to the biomedical translation fund.

Skills shortage requires education revamp
At the heart of the ISA's innovation agenda was a re-booting of the educational and training system.
Despite recent fears that automation will destroy jobs, the ISA forecast that a "shortage of workers is a more likely problem than a shortage of jobs".
It forecast a looming retirement boom from an ageing population would create a 6 per cent skills shortage by 2030.
At the same time, technology meant 92 per cent of future jobs would need digital skills and 45 per cent would require people who can configure digital systems.
The ISA recommended "refining" immigration restrictions to attract specialists and entrepreneurs and increase training for teachers in science, technology, engineering and mathematics.
ISA deputy chairman and chief scientist Alan Finkel told The Australian Financial Review it was essential the future workforce had strong knowledge in disciplines as well as "21st century" skills such as creativity and problem-solving.
However, he said teachers' training and knowledge of their own disciplines needed to improve.
"There's no point raising the bar of students' aspirations if you don't also coach them to clear the bar."
The ISA recommended that teachers spend a minimum number of hours every year in professional development for their specific discipline to ensure their knowledge is up to date.
The report also called for a review of the vocational education and training system to ensure it is more responsive to new technologies and to link VET funding to employment outcomes.

Links

• 'National missions' set to reboot Malcolm Turnbull's innovation agenda
• Innovation and Science Australia
• ISA 2030 Strategy at a glance

Climate Scientists Explore Hidden Ocean Beneath Antarctica’s Largest Ice Shelf

The Conversation - Craig Stevens | Christina Hulbe

The team used hot-water drilling gear to melt a hole through Antarctica’s Ross Ice Shelf to explore the ocean below. Christina Hulbe, CC BY-ND

Antarctica’s Ross Ice Shelf is the world’s largest floating slab of ice: it’s about the size of Spain, and nearly a kilometre thick.
The ocean beneath, roughly the volume of the North Sea, is one of the most important but least understood parts of the climate system.
We are part of the multi-disciplinary Aotearoa New Zealand Ross Ice Shelf programme team, and have melted a hole through hundreds of metres of ice to explore this ocean and the ice shelf’s vulnerability to climate change. Our measurements show that this hidden ocean is warming and freshening - but in ways we weren’t expecting.


Instruments travelling 360m down a bore hole, from the snow-covered surface of the Ross Ice Shelf through to the ocean below the ice. After splash-down at about 60m, they move through the bubble-rich upper ice and down into the dark bubble-free lower reaches of the ice – passing embedded sediment that left the coast line centuries ago.

A hidden conveyor belt
All major ice shelves are found around the coast of Antarctica. These massive pieces of ice hold back the land-locked ice sheets that, if freed to melt into the ocean, would raise sea levels and change the face of our world.
An ice shelf is a massive lid of ice that forms when glaciers flow off the land and merge as they float out over the coastal ocean. Shelves lose ice by either breaking off icebergs or by melting from below. We can see big icebergs from satellites - it is the melting that is hidden.
Because the water flowing underneath the Ross Ice Shelf is cold (minus 1.9C), it is called a “cold cavity”. If it warms, the future of the shelf and the ice upstream could change dramatically. Yet this hidden ocean is excluded from all present models of future climate.

This satellite map shows the camp site on the Ross Ice Shelf, Antarctica. Ross Ice Shelf Programme, CC BY-ND

There has only been one set of measurements of this ocean, made by an international team in the late 1970s. The team made repeated attempts, using several types of drills, over the course of five years. With this experience and newer, cleaner, technology, we were able to complete our work in a single season.
Our basic understanding is that seawater circulates through the cavity by flowing in at the sea bed as relatively warm, salty water. It eventually finds its way to the shore - except of course this is a shoreline under as much as 800 metres of ice. There it starts melting the shelf from beneath and flows across the shelf underside back towards the open ocean.

Peering through a hole in the ice
The New Zealand team – including hot water drillers, glaciologists, biologists, seismologists, oceanographers – worked from November through to January, supported by tracked vehicles and, when ever the notorious local weather permitted, Twin Otter aircraft.
As with all polar oceanography, getting to the ocean is often the most difficult part. In this case, we faced the complex task of melting a bore hole, only 25 centimetres in diameter, through hundreds of metres of ice.

A team of ice drillers from Victoria University of Wellington used hot water and a drilling system developed at Victoria to melt a hole through hundreds of metres of ice. Craig Stevens, CC BY-ND

But once the instruments are lowered more than 300m down the bore hole, it becomes the easiest oceanography in the world. You don’t get seasick and there is little bio-fouling to corrupt measurements. There is, however, plenty of ice that can freeze up your instruments or freeze the hole shut.

A moving world
Our camp in the middle of the ice shelf served as a base for this science, but everything was moving. The ocean is slowly circulating, perhaps renewing every few years. The ice is moving too, at around 1.6 metres each day where we were camped. The whole plate of ice is shifting under its own weight, stretching inexorably toward the ocean fringe of the shelf where it breaks off as sometimes massive icebergs. The floating plate is also bobbing up and down with the daily tides.

The team at work, preparing a mooring. Christina Hulbe, CC BY-ND

Things also move vertically through the shelf. As the layer stretches toward the front, it thins. But the shelf can also thicken as new snow piles up on top, or as ocean water freezes onto the bottom. Or it might thin where wind scours away surface snow or relatively warm ocean water melts it from below.
When you add it all up, every particle in the shelf is moving. Indeed, our camp was not so far (about 160km) from where Robert Falcon Scott and his two team members were entombed more than a century ago during their return from the South Pole. Their bodies are now making their way down through the ice and out to the coast.

What the future might hold
If the ocean beneath the ice warms, what does this mean for the Ross Ice Shelf, the massive ice sheet that it holds back, and future sea level? We took detailed temperature and salinity data to understand how the ocean circulates within the cavity. We can use this data to test and improve computer simulations and to assess if the underside of the ice is melting or actually refreezing and growing.
Our new data indicate an ocean warming compared to the measurements taken during the 1970s, especially deeper down. As well as this, the ocean has become less salty. Both are in keeping with what we know about the open oceans around Antarctica.
We also discovered that the underside of the ice was rather more complex than we thought. It was covered in ice crystals – something we see in sea ice near ice shelves. But there was not a massive layer of crystals as seen in the smaller, but very thick, Amery Ice Shelf.
Instead the underside of the ice held clear signatures of sediment, likely incorporated into the ice as the glaciers forming the shelf separated from the coast centuries earlier. The ice crystals must be temporary.
None of this is included in present models of the climate system. Neither the effect of the warm, saline water draining into the cavity, nor the very cold surface waters flowing out, the ice crystals affecting heat transfer to the ice, or the ocean mixing at the ice fronts.
It is not clear if these hidden waters play a significant role in how the world’s oceans work, but it is certain that they affect the ice shelf above. The longevity of ice shelves and their buttressing of Antarctica’s massive ice sheets is of paramount concern.

Links

• Antarctic glacier's unstable past reveals danger of future melting
• Record high to record low: what on earth is happening to Antarctica’s sea ice?
• Don’t worry about the huge Antarctic iceberg – worry about the glaciers behind it
• Shrinking of Antarctic ice shelves is accelerating
• Tipping point: how we predict when Antarctica’s melting ice sheets will flood the seas