Drilling into Peter Barrett's career

Emeritus Professor Peter Barrett FRSNZ, FGS explains how he became Aotearoa New Zealand's pre-eminent Antarctic scientist and climate change spokesperson.

Peter Barrett speaking at the Peter Barrett Symposium in Nov 2020

Science can thank the parents of Emeritus Professor Peter Barrett FRSNZ, FGS for letting him roam the Waikato countryside when other teenagers were up to less innocent pursuits.

Peter, the inaugural director of Te Herenga Waka—Victoria University of Wellington’s Antarctic Research Centre Te Puna Pātiotio, was honoured late last year with an eponymously named symposium that celebrated many aspects of his scientific life and his 25 expeditions to the ice.

Director of Te Puna Pātiotio from 1972 to 2007, he guided a growing team of researchers and pioneered geological drilling in the Ross Sea, establishing the age of historic Antarctic glaciation and later recording Antarctic ice sheet dynamics and climate history.

The 80-year-old’s achievements have changed the way the world sees itself, with seminal contributions to the theory of plate tectonics and to climate change science.

As a teenager growing up on a dairy farm in the 1950s, he took the first steps on his geological journey, going caving with friends near Hamilton and then in the Te Kuiti district.

“On our first trip we found a stream flowing  into a cave that had a rumbling sound, which turned out to be a waterfall. That cave, now called ‘Rumbling Gut’, turned out to have some spectacular formations, 30 metres high with stalactites hanging down, all
glistening. We were hooked.

“I had wonderful parents who allowed me to do these things without asking too many questions.”

Caving was the catalyst for studying the Te Kuiti Limestone for his Master’s thesis at the University of Auckland, leading to a chance offer from a caving buddy in 1962 to join a United States expedition to the Ellsworth Mountains in Antarctica. That led to a PhD project at Ohio State University on the Gondwana strata of the Central Transantarctic Mountains.

It was here, in December 1967, while mapping rock layers near the Beardmore Glacier, Peter made a discovery that showed Antarctica had once been part of a Gondwana supercontinent.

“On this day, we were measuring our way up Graphite Peak. We were on a sandstone bluff, an old braided-river deposit, with patches of gravel, counting pebbles, and I spotted one that was quite dark-coloured and the network patterns within the pebble looked like a piece of bird bone.

“It was deeply embedded among the rest of the stones. We had to extract it, chipped all round it, but we couldn’t get it out as a single block.

“We laid a cloth on the ground, put all the pieces carefully together, wrapped them up, and took them back to the tent. We decided the best way to get it back to the US was to reassemble it with pancake mix.”

Later, American Museum of Natural history paleontologist Professor Ed Colbert confirmed it was part of the lower jaw of an amphibian about 200 million years old and the first tetrapod to be found in Antarctica.

In November 1970, an expedition led by a colleague returned to the same strata and found more fossils, this time including a species known also from South Africa and China, “and that really nailed it”.

About that time, Peter took up a postdoctoral fellowship at the University and he was then appointed as a senior lecturer in Geology and the inaugural director of Te Puna Pātiotio.

Then, in late 1972, he went on a 10-week voyage to the Antarctic on the first ship to drill in the Ross Sea.

“I was expecting we would drill into the Beacon Sandstone, striking horizontal layers that cap the Transantarctic Mountains. But instead we drilled into hundreds of metres of glacial deposits, which went back over 25 million years. This surprising discovery raised the question of just when and why did the ice sheet first form.”

Another mind-expanding experience was a 1978 article in Nature by glacial geologist and former Ohio State University colleague Dr John Mercer.

“This had the alarming headline, ‘West Antarctica and CO2 – threat of disaster’. John had been watching the rising atmospheric CO2 levels recorded at South Pole Station from the late 1950s.

“He linked this with the well-established rise in temperature for rising CO2, and his observation was that the floating ice shelves of the Antarctic Peninsula were close to their temperature limit for breaking up. With a small temperature rise, the break-up would  lead the glaciers feeding them to speed up, and eventually to the West Antarctic Ice Sheet collapsing.

“The glaciologists at the time just didn’t believe it. But by the 1990s, when the ice shelves were starting to collapse as that region warmed, people realised John was right.

“John’s paper made climate change part of my life in quite a crucial way—learning more about when and why the early ice sheets formed had more purpose than just satisfying curiosity. So I spent the next 20 years running drilling projects to recover cores recording the changes in ice and climate through time.

“By the late 1990s, our drill-core record from the edge of the Antarctic Ice Sheet matched well with global cooling and declining CO2 trends over the past 50 million years. It was clear that if CO2 emissions continued to rise we would have the climate of an ice-free world by 2100.

“This was behind my public statement in 2004 on receiving the Marsden Medal that if we don’t change our ways, and reverse the rise in CO2, this will lead to the end of civilisation as we know it by the end of the century. At the time, my colleagues were horrified, but now that’s a common view.”

To spread the word, Peter worked with geologist and film maker Associate Professor Simon Lamb from the University to make an award-winning film revealing the reality of climate change: Thin Ice—the Inside Story of Climate Science, available free online and to schools.

Peter has a string of honours to his name, including being Wellingtonian of the Year in 2006. Two years later, he was invited to be Patron of the New Zealand Antarctic Society (succeeding Sir Edmund Hillary), and in 2010 he was awarded the New Zealand Antarctic Medal for services to Antarctic science.

In 2011, he was made an Honorary Fellow of the Geological Society of London, a title only held by 70 people worldwide.

His last working expedition to Antarctica was in 2003.

“I’m just delighted to have been able to do something I found fascinating, to have the chance to work with good people, and to have contributed to the growing pool of knowledge on changing climate so we can avert the worst.

“I’ve been worried about the rise in hubris, and decline in respect for evidence-based discussion, in the wider world, although less so in New Zealand since the change in government in 2017. This change, and the lessons from COVID-19 we seem to be learning on the value of science, give me hope.”