Our Changing World

Emma Carroll talks about the return of southern right whales from the edge of extinction and a project asking the public to report whale sightings.

Researchers are using satellite tracking to find out where New Zealand's southern right whales, or tohorā, go when they leave their winter breeding hotspot at the subantarctic Auckland Islands.

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Tohorā used to be a common sight around New Zealand's shores. Then, commercial whaling took them to the edge of extinction.

The New Zealand southern right whale population plummeted to perhaps just 40 animals by 1920, from more than 30,000 before Europeans arrived in the late 18th century.

Since whaling ended and the whales have been protected their numbers have been climbing steadily. The most recent population estimate, from 2009, is about 2,000 whales.

The whales' main breeding ground is at Port Ross, in the Auckland islands, and researchers - who have been studying the population there for several decades - have counted up to 200 individuals there in winter, including 50 cow-calf pairs, in the large harbour's sheltered waters.

"It's not a big place. It's basically whale soup," says Rutherford Discovery Fellow Emma Carroll, from the University of Auckland.

Where do the whales go in summer?

Emma Carroll is currently leading an expedition to the Auckland islands, and one of the team's goals is to attach six satellite tags to find out where the whales go when they leave the breeding ground.

Only two tohorā have been successfully tagged and tracked prior to this, and the pair did very different things.

An adult male (tag number 96373) moved north from the Auckland islands to Stewart Island, stopped transmitting for a while and then turned up south of Western Australia.

The adult female (tag number 96374) headed west to feeding grounds along the subtropical convergence, south of Australia, where warm subtropical waters meet cooler subantarctic waters.

Public help needed to sight whales

Although right whales usually return to breed in the place they were born, meaning most animals return to the Auckland islands, Emma says that small numbers of right whales are also returning to mainland New Zealand.

She says there have been large groups seen off Southland, and two females have each given birth to two calves off northern New Zealand.

"Hopefully that's the beginning of that new knowledge of the mainland as a good place to come and have babies," says Emma…

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In search of southern right whales and digitising old weather records to predict future climate.

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Take some old weather records. Add citizen scientists. Mix in machine learning. Result = something that might help predict future weather patterns.

Take some old weather records. Add citizen scientists. Mix in machine learning from Microsoft's 'AI for Earth' project.

And what you end up with is something that might help predict future weather patterns.

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By all accounts, the winter of 1939 was a long, cold, snowy one. In the last week of July, there were reports of snow in many places, from Bluff to the lighthouse at Cape Reinga.

It's been dubbed 'the week it snowed everywhere,' and NIWA researchers have scoured old weather records to find out exactly where it snowed, and how much snow fell.

They hope these records from the past will help predict snowy weather in the future more precisely.

Andrew Lorrey says NIWA has countless boxes of old weather records, collected from around New Zealand and the Pacific. Local observers filled out precise hand-written daily reports of sunshine hours, rainfall, wind speed and direction - and, sometimes, snowfall.

"They were quite dutiful in doing the rain and the obs every day, no matter what was going on," says Andrew.

He says NIWA still has the first official weather records for New Zealand, that go back to the 1850s. "Basically, the barracks at Albert Park , the Royal Engineers, 1852 ... those were the first truly official Government regimented observations."

Andrew has also helped find New Zealand's earliest, unofficial weather records, from Reverend Richard Davis. The Reverend's weather diary was found in the Special Collections of the Auckland Public Library. It goes back to 1839 with daily weather observations from the Far North, including records of snow persisting on the ground for several days.

"We're wanting to understand those types of extremes, and how and why they happen for New Zealand. And whether they are something we're going to see less of, or is it something we're going to see more of with climate change," says Andrew.

Andrew says it seems that Northland experiences snow every 60-80 years.

The Davis diary, which has UNESCO Memory of the World status, has been copied and digitised, and Andrew has made a start on getting the official weather records digitised as well.

He began with records from the 1939 week of snow, using citizen scientists to decipher the hand-writing and enter the data. He says eight observations of the same number gives a very reliable data set…

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Tiny plants that live on the underside of sea ice form an upside-down garden that feeds krill and is the base of the Antarctic food web.

Sea ice in Antarctica is home to an upside-down garden that is the powerhouse at the bottom of Antarctic food webs.

But what will happen to this remarkable ecosystem in a warming world?

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Microscopic plants bloom on the underside of the Antarctic sea ice in spring, as soon as the sun returns.

Less than one percent of ambient light makes it through the sea ice, which averages 1.7 to 2 metres thick at Cape Evans, but it is enough light to trigger the plants to begin photosynthesis.

These ice algae, along with bacteria and viruses, live in tiny pockets and channels in the bottom few centimetres of the ice. These pockets between the ice crystals are created by brine which is excreted as seawater freezes.

The tiny algae and microbes are grazed on by young krill and forms a vital part of their diet.

Krill underpin the Antarctic food web, and seals, penguins and whales all rely on the huge pulse of krill that follows the annual spring algae bloom.

New Zealand and Australian researchers have been studying this under-ice community for many years at Cape Evans, on Ross Island.

https://www.youtube.com/watch?v=fZy5QiG5haY

Andrew Martin, from the University of Tasmania, says the current research, funded by the New Zealand Antarctic Research Institute, aims to understand what might happen to Antarctica in the future as global temperatures rise.

He says that in the next 80 years, Antarctic sea ice is predicted to shrink in area and thickness by a third. As well, increasing snow and wind will change how much light gets through the ice.

Andrew and colleagues are trying to measure and predict how these changes will affect life in Antarctica, especially the 'grass of the sea' under the ice.

In November 2019, the researchers used coloured perspex panels screwed onto the ice to mimic changing light conditions. Vanessa Lucieer and the On Thin Ice team from the Institute of Marine and Antarctic Studies at the University of Tasmania, used hyperspectral scanning and remote operated vehicles, as well as ice cores, to measure how microscopic life responded.

A hyperspectral camera composes an image that uses the full spectrum of light and goes beyond the range visible to the human eye.

Andrew says they were surprised to discover that there was more abundant microbial life under the red, green and blue acrylic panels than under the surrounding sea ice. The make-up of the communities had also changed…

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Researchers are using hot water to drill through the Ross ice shelf, to discover what has happened to Antarctic ice during previous periods of warm climates.

Hot water is playing a key role in understanding how Antarctic ice responds to a warming world.

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Ninety percent of the world's freshwater is locked up as ice in Antarctica and scientists are working to better understand what might happen with all that ice in a warming world.

Researchers from the Antarctic Research Centre at Victoria University of Wellington and from the University of Otago are studying the Kamb Ice Stream, an enormous river of ice that drains from West Antarctica and feeds the world's largest floating ice shelf, the Ross Ice Shelf.

Scientists have discovered that ice streams turn on and off, stalling for decades and even hundreds of years before starting to move again. Huw Horgan, from Victoria University of Wellington, says that Kamb ice stream stalled about 170 years ago and researchers are investigating why.

The research is part of an Antarctic Science Platform project called Antarctic Ice Dynamics.

The 2019 research season took place on the Siple Coast, which is the grounding line of the West Antarctic Ice Sheet, where the ice meets the ocean and starts to float, becoming the Ross Ice Shelf. It is as far south as the ocean reaches anywhere in the world.

In hot water

The researchers use a hot water drill to melt through 600-metres of ice, to reach the water and sea floor below.

Driller Darcy Mandeno, from Victoria University of Wellington, says the drill will take about 12 hours to make a 35 centimetre diameter hole, through which the researchers can lower various instruments to measure physical attributes of the water, as well as drill a short sediment core.

Crossing Antarctica

The first full traverse across Antarctica was made by Sir Vivian Fuchs. Sir Edmund Hillary and his Kiwi team famously drove Massey Fergusson tractors to meet Fuchs at the South Pole, as part of the Commonwealth Trans-Antarctic expedition.

Every year, the United States Antarctic programme drives three traverses from McMurdo Station to the South Pole, dragging sleds carrying fuel and supplies.

In 2017, the Antarctica New Zealand started its own traverses, dragging scientific equipment to remote field camps on the Ross Ice Shelf.

Traverse navigator Daniel Price, a sea ice researcher at the University of Canterbury, selects safe routes for the traverse to follow. He uses satellite radar images to identify and plot large crevasses which must either be avoided or blown up to create a safe crossing…

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Alison Ballance eavesdrops on the songs of the world's southern-most mammal, the Weddell seal, and finds out about sea ice.

Weddell seals are large blobs when they are ashore sleeping, but underwater they transform into the most graceful dancers and the most incredible songsters.

Seal song is a mixture of space sounds, jungle noises and even construction noises, which carries for many kilometres in the almost freezing water under the sea ice.

Dive into the underwater song world of the Weddell seal

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Weddell seals near Scott Base are being studied by a NIWA-led Ross Sea research and monitoring programme, known as Ross RAMP. The programme is monitoring the effectiveness of the very large Ross Sea marine protected area.

Weddell seals are the southern-most living and breeding mammal in the world.

Females give birth on the sea ice in late spring. They feed their pups a rich milk that sees them gain two kilograms a day and be weaned within just a few weeks. Female Weddell seals lose up to 40 percent of their body weight while they are feeding their pups

In 2019, about 20 Weddell seals gave birth in the pressure ridges in front of Scott Base. It is the first time in more than 50 years that such numbers have bred there.

Following the establishment of Scott Base, seals were killed to feed the huskies and the breeding seals moved away, although individuals continued to use the breathing holes in the pressure ridges and haul out to rest.

The research team are putting data loggers and video cameras on females with pups to find out what they eat and where they go.

Sea ice

Greg Leonard and Maren Richter, from the University of Otago, spent several weeks in November 2019 driving skidoos around on the sea ice in McMurdo Sound.

They were towing a system that could measure the thickness of the sea ice below, identifying not just the solid sea ice but also the less dense layer of platelet ice crystals that grows under the sea ice here. Platelet ice can be up to seven metres thick in parts of the Sound, as a result of the proximity of the enormous Ross Ice Shelf.

The annual land-fast sea ice in McMurdo Sound, which forms each winter and breaks up in summer, averages 1.6 to 2 metres thick.

Voices from Antarctica - listen to the full series

Voices from Antarctica 1: Ice Flight

Voices from Antarctica 2: Scott Base

Voices from Antarctica 3: Flags to physics

Voices from Antarctica 4: best journey in the world

Voices from Antarctica 5: Waiting for Emperors

Voices from Antarctica 6: Seal songs

Voices from Antarctica 7: What the ice is saying…

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Michelle Dalrymple, winner of the 2019 Prime Minister's Science Teacher's Prize, says being mathematically literate is an important life skill.

Michelle Dalrymple says there is no such thing as a math's brain.

The winner of the 2019 Prime Minister's Science Teacher's Prize says that not only is everyone capable of being statistically and mathematically literate, but it is an important life skill.

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The Christchurch teacher is the first maths teacher to win the Prime Minister's Science Teacher Prize.

Michelle is Mathematics and Statistics Faculty Head at Cashmere High School. She says every student deserves a champion and is devoted to sharing her research and knowledge with other teachers around the country.

2019 Prime Minister's Science Prize winners

'Melting ice and rising seas' team wins 2019 Prime Minister's Science Prize.

Laser physicist wins 2019 Prime Minister's Emerging Scientist Prize.

Tūhoe astronomer wins 2019 Prime Minister's Science Communication Prize.

Maths teacher wins 2019 Prime Minister's Science Teacher's Prize.

Young inventor wins 2019 Prime Minister's Future Scientist Prize.

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A team finding links between melting ice sheets in Antarctica and rising sea levels in NZ has won the 2019 Prime Minister's Science Prize.

New Zealand's most valuable science prize, worth half a million dollars, has gone to a large team of researchers finding links between melting ice sheets in Antarctica and rising sea levels in New Zealand.

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The 'Melting ice and rising seas' team from Victoria University of Wellington, NIWA and GNS Science is the winner of the prestigious 2019 Prime Minister's Science Prize.

The team has found evidence that Antarctic melt due to climate change could contribute to global sea level rise of 1.4 metres by the year 2100, rather than the one metre that the Intergovernmental Panel on Climate Change (IPCC) predicted in 2013.

When the effect of land subsidence is taken into account the rise could be as much as two metres for some places in New Zealand.

And the researchers warn that a global temperature rise of 2°C will commit the planet to a long-term rise of tens of metres.

Engine room of sea level change

Starting about 15 years ago the team, which includes geologists, glaciologists, climate and social scientists, began drilling ice and sediment cores in Antarctica.

The cores have revealed how the Antarctic ice sheets have advanced and retreated as the climate has warmed and cooled over the past 20 million years.

The data have been used in ice sheet and climate models to show the impact of Antarctic melting under a warming climate.

Professor Tim Naish, from the Antarctic Research Centre at Victoria University of Wellington, says his early research in global sea levels was brought into focus when he began working in Antarctica.

"It was a chance to go to the engine room of where these sea level changes were coming from," says Prof Naish.

Prof Naish says sediments are a wonderful archive of past climates.

'For me it's always been about using the rocks to understand how sea-level has changed. Or, by drilling about the Antarctic margin, how the Antarctic ice sheet has changed through time, particularly during periods of past warmth, which are relevant to the world we're heading towards with climate warming," says Prof Naish.

Lessons from the past

Prof Naish says that we currently have 416 parts per million carbon dioxide in the atmosphere. The last time the world had C02 levels that high was three million years ago during the Pliocene warm period.

As a result, he says, the "West Antarctic ice sheet went away. Bits of East Antarctica went away. And global sea-level was up to 20 metres higher."…

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Student Thomas James wanted to help his elderly neighbour, so he invented a wheelie bin robot to take her large recycling bin to the kerb.

Burnside High School student Thomas James wanted to help his elderly neighbour, so he invented a wheelie bin robot to take her large recycling bin to the kerb.

The invention has won him the 2019 Prime Minister's Future Scientist Prize.

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Thomas used lego models for his first prototype before learning about micro-processors, programming, autonomous navigation and sourcing the many intricate components he needed to build a full-size self-navigating robot.

His nominator says he is a very talented engineer who's developed and produced a system that adult technologists would struggle to design and make.

2019 Prime Minister's Science Prize winners

'Melting ice and rising seas' team wins 2019 Prime Minister's Science Prize.

Laser physicist wins 2019 Prime Minister's Emerging Scientist Prize.

Tūhoe astronomer wins 2019 Prime Minister's Science Communication Prize.

Maths teacher wins 2019 Prime Minister's Science Teacher's Prize.

Young inventor wins 2019 Prime Minister's Future Scientist Prize.

Go to this episode on rnz.co.nz for more details

Winners of the 2019 Prime Minister's Science Prizes include a team studying melting ice and rising seas, a maths teacher and a young inventor.

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