Mt Tarawera lies within one of the most productive rhyolite volcanoes in the world - the enormous Ōkataina caldera near Rotorua. Scientists are trying to understand why rhyolitic eruptions can vary between explosive and non-explosive. Photo / Getty Images
Mt Tarawera lies within one of the most productive rhyolite volcanoes in the world - the enormous Ōkataina caldera near Rotorua. Scientists are trying to understand why rhyolitic eruptions can vary between explosive and non-explosive. Photo / Getty Images
New Zealand’s biggest backer of “blues skies” research - the Royal Society Te Apārangi-administered Marsden Fund - awarded nearly $80 million to 113 research projects this year. Science reporter Jamie Morton looks at five of them.
What makes our biggest volcanoes go bang?
They make some of the biggest bangs on Earth. Other times, they erupt somewhat less spectacularly, in the form of lava flows and domes.
Just why a certain type of magma, called rhyolite, blows in very different ways isn’t understood – but the answer could be found right here in Aotearoa.
Our fiery Taupō Volcanic Zone holds the planet’s two most frequently active rhyolite volcanoes – the enormous Taupō and Ōkataina calderas – both of which have produced huge eruptions.
Lake Taupō itself essentially fills the hole left by one of these - the gigantic Oruanui eruption around 25,400 years ago, in which more than 1100 cubic kilometres of pumice and ash was spewed into the planet’s atmosphere.
Okataina, meanwhile, has erupted six times in the last 10,000 years – most recently in 1886, with the violent (but basaltic) Mt Tarawera event that destroyed the famous Pink and White Terraces.
Sometimes, in individual eruptions, activity switches between explosions and other processes.
In a new study, GNS Science’s Dr Shane Rooyakkers and his team hope to find what controls this contrast within magma samples from our volcanoes.
“By studying these volcanic products, we aim to advance understanding of processes that occur inside volcanic conduits as magma ascends to the surface and find out what tips the balance between explosive and non-explosive activity.”
In what will prove the first decompression experiments ever conducted with New Zealand magmas, the scientists will use high temperatures in controlled laboratory exercises to simulate how they rise.
This would allow the team to compare the magma products from their experiments to what had been created by nature.
Further, it would help them unravel the complex interplay between specific volcanic processes, and their ultimate effects on eruption styles.
“This will be a critical step in advancing our understanding of evolving hazards during rhyolite eruptions.”
Rooyakkers said a series of hui would help to explore the alignment of the research with iwi interests, and learn how mātauranga Māori could help develop shared understanding of the landscapes and volcanic history of the volcanoes.
Where exactly do our eels go to spawn?
Scientists are set to pin-point the mysterious spawning grounds of New Zealand's native tuna. Photo / NZME
They’re the slimy, slithery wayfarers of our waterways that are as much a part of Aotearoa as the kiwi and kakapo: yet there’s so much about tuna that we don’t understand.
And scientists have one big question, in particular: where exactly do our eels go when they leave New Zealand?
A new project, led by Otago University’s Dr Amandine Sabadel, aims to shed fresh light on where the longfin and shortfin eel spawns, and how their larvae are dispersed.
Adult tuna leave New Zealand and swim thousands of kilometres across the ocean to spawn somewhere unknown in the western South Pacific Ocean before they die.
The larvae then travel via ocean current back to New Zealand where they grow and mature.
While researchers have tried to track the migration over many decades using satellite tracking, they’ve never successfully pin-pointed that mystery spawning location.
One method identifies unique stable isotopes, which are chemical markers specific to the local environment that will be imprinted within the tuna’s tissue as they develop – making it possible to locate an animal at a specific time or place.
A second and complementary method makes use of environmental DNA. When adult tuna or their larvae travel through water, they will leave traces of their DNA behind them, and the measurement of eDNA helps researchers to identify their presence or absence in the environment.
“My area of expertise is in using environmental DNA and RNA to identify organisms within the environment,” said co-researcher and Cawthron Institute molecular surveillance team leader Xavier Pochon.
“eDNA surveillance uses genetic rather than chemical markers, but the two technologies will be integrated to try and track our New Zealand eels’ migratory pathways and pinpoint their spawning location.”
University of Auckland lecturer Dr Kiri Dell is leading a new study exploring Māori well-being amid the te reo boom. Photo / Elise Manahan, University of Auckland
Half a century after the Māori Language Petition was delivered to Parliament, te reo Māori has exploded among Pākehā.
Yet, amid widespread efforts to normalise te reo across our culture, where does that leave Māori themselves?
That’s a question to be explored in a three-year project led by Waipapa Taumata Rau University of Auckland academic Dr Kiri Dell.
In recent years, millions of dollars have been poured into language revitalisation, yet fewer than 20 per cent of Māori speak te reo confidently.
Meanwhile, Pākehā engagement with te reo Māori is booming.
Dell’s research project will investigate the many facets and implications for the country to become a te reo speaking nation – particularly the barriers facing Māori.
“The elevation of the Māori language as our nation’s priority towards an empowered Treaty partnership has intensified Pākehā consumption of te reo Māori,” she said.
“On the one hand, its growth, increased distribution, and usage are viewed as positive when it comes to language revitalisation efforts.
“Yet, on the other hand, issues seem to be emerging, with some Māori feeling marginalised by current revitalisation efforts, perceiving them as focusing on Pākehā accessing, speaking, and using te reo Māori.”
The study will involve an analysis of media content, along with a series of interviews.
Dell pointed out the research didn’t intend to critique revitalisation efforts, but to observe and assess Māori well-being in relation to strategies.
“Maintaining Māori well-being amidst the transition to a te reo speaking country is critical for this nation’s positive social transformation and smooth bicultural evolution.”
Otago University's Professor Michelle Glass. Photo / Supplied
While most of us might know cannabinoids as high-making compounds in marijuana, for scientists, they pack the potential to treat a wide range of diseases.
The “cannabinoid” receptors in our own brain, called CB1 receptors, happen to outnumber many other types.
With a broad range of physiological functions, they’ve increasingly been eyed as useful targets to treat conditions varying from pain and psychosis to appetite stimulation and glaucoma.
Directly activating them, however, can come with some unwanted effects – namely psychoactivity.
Now, a team led by Otago University pharmacology academic Professor Michelle Glass aims to find whether these compounds can be cleverly harnessed, with fewer adverse effects.
“Cannabinoids like THC produce their effect by activating your cannabinoid receptors. While they have lots of therapeutic potential, they also generate a very unnatural pattern of activity,” she explained.
“When you take the drug, all of your receptors in all brain regions are activated, whereas normally there would be a range in activities in different brain regions, some on, some off at any given time.”
She and colleagues believe drugs that just enhance that “natural pattern” of activity would be much better tolerated by users.
Their project plans to develop such drugs – and then test them to refine what chemical structure is needed.
“We’d really like to come away with a lead compound that could be developed further and taken into clinical trials,” she said.
“This could help treat the wide range of disorders for which activation of cannabinoid receptors has been suggested to be useful, without producing psychoactivity.”
What can Earth’s past big melts tell us about the future?
Scientists aim to get a clearer picture of Antarctic melt in abrupt climate events in the Earth's past. Photo / Nasa
To climate scientists, few questions are as worrying as what a warming world means for our ice sheets – and thus the rest of the planet.
But the geological record gives us some clues as to what’s happened before.
In a warming event that followed the end of the last great ice age, Northern Hemisphere ice sheets rapidly melted to pump vast volumes of freshwater into the north Atlantic, within a very short period of time.
This in turn slowed down the ocean current that carried warm waters north into Europe, and over a period of a few decades plunged it back into a short, but sharp cold period – a scenario exaggerated for the disaster blockbuster, The Day after Tomorrow.
Apart from Greenland, very little Northern Hemisphere ice sheets exist today, but large ice sheets in Antarctica do exist.
“Due to human-induced warming, we think they are approaching a tipping point whereby accelerated melting will occur if carbon dioxide in the atmosphere continues to increase,” Victoria University’s Associate Professor Associate Professor Robert McKay said.
“We don’t know what the climate implications of this meltwater input into the Southern Ocean would be.”
Because the ancient Northern Ice Sheets were so much larger than Antarctica’s ones – and hence had obscured the geological record over the past 2.5 million years - it had been difficult for scientists to tease out what had happened in the Southern Ocean.
“However, we recently recovered a unique set of sediment core with the International Ocean Discovery Programme expedition to the Ross Sea that were perfect to address this question,” McKay said.
“At a time period when climate was only marginally warmer than today, they hold a record of iceberg armadas being discharged from Antarctica, while fossils and geochemical data indicate pulses of meltwater were also associated with these events.
“The pattern of these events looks very similar to those of the Northern Hemisphere events that had been so well documented by other workers.”
McKay suspected this data could fill in the missing piece of the puzzle, and refine today’s climate models.
“Climate models do currently show that meltwater sourced from future ice sheet melt can change weather patterns all over the world, although this depends on the source and magnitude of the meltwater,” he said.
“We believe our data will help to verify what the magnitude of such events have been in the past.
“To do this, we will use climate models to assess the global impacts of these events, and will then target geological records in New Zealand to assess if those models accurately predicted shifts in our climate caused by these ice sheet melting events.”
