Impact of Vanuatu volcanic eruption focus of research

The major eruption of Vanuatu’s Kuwae volcano in the mid-1500s continues to echo through generations in oral stories, and now through scientific research.

University of Auckland PhD candidate Sönke Stern has been investigating the eruption’s global climate impact, a topic that has long fascinated academics.

The theme for Aotearoa’s first Vanuatu Bislama Language Week focuses on climate:
‘Tokabaot Klaemet Jenj – hemi ril mo yumi mas lukaotem laef – Talk about Climate Change – it is real, and we must look after life’.

Stern’s research connects the Kuwae eruption to global climate effects, visible in paleoclimate datasets such as ice cores and tree rings dating back to the 1450s CE.

“The idea from the very beginning was to find out whether the volcanic eruption caused global climate impact,” says Stern.

“Our shared project with archaeologists and oral historians aimed to reconstruct both the volcano’s impact on the local population and its wider impact on society.”

Travelling from Germany to New Zealand, Stern was fortunate to join Auckland University's research project examining the Kuwae caldera. This is a large, mostly submarine volcanic depression located between Epi and Tongoa islands in central Vanuatu. Measuring approximately 12 km by 6 km, the caldera was formed by the massive eruption.

“I’ve always been super curious about nature, which led me to geology. The sheer power of volcanoes has always fascinated me. I think it started after watching Dante’s Peak as a kid.”

Stern’s passion for geology and other cultures has taken him around the world conducting fieldwork. He describes witnessing volcanic eruptions as unforgettable experiences.

Oral histories from Vanuatu recount devastating earthquakes, tsunamis, and the disappearance of land. These stories are now supported by geological evidence. The Kuwae eruption is believed to have contributed to global climate cooling and remains one of the largest eruptions of the last 10,000 years.

Due to the remoteness of the location, data on the eruption’s impact required further investigation. Stern notes that in geological terms, the event is relatively recent.

“That’s the first thing you learn as a young geology student. Your brain switches when it comes to time scale. A million years is not that long ago. We deal with stuff a whole lot older than that.”

The Covid-19 pandemic delayed Stern’s planned fieldwork in 2020, but he eventually travelled to Vanuatu in mid-2022. After arriving in Port Vila, he spent six weeks in the Shepherd Islands, including five weeks on Epi and Tongoa, working closely with local communities.

“Learning Bislama within a few weeks was as challenging as it was rewarding. Being able to communicate my research to the local communities while staying with them on-site was an experience I’ll never forget.”

Stern returned in 2023 to conduct a boat-based survey of the ocean floor, studying the collapsed volcano and collaborating with the Vanuatu Meteorology and Geohazards Department (VMGD).

He acknowledges the vital support of project partners in archaeology and history, including VMGD, the Vanuatu Cultural Centre, and communities across Epi, Tongoa, Émaé and Tongariki.
“This project wouldn’t have been possible without the cooperation and incorporation of local knowledge.”

Now based in Reefton, New Zealand, Stern has taken up a new role in exploration geology with a large-scale gold mining operation.

“Academia is a very competitive field, especially in recent years. Moving into industry has allowed me to stay in the field, and also in Aotearoa, New Zealand.
I’m a very outdoorsy person. I can get on my bike and within ten minutes be in the bush by myself. I can’t do that back home.”