‘We’re losing our glaciers’: scientist caches ice from the Antarctic climate record
As coordinator and caretaker at an ice-core facility, Rebecca Pyne preserves these precious records of past climate
Ice cores contain so much information from which we can piece together past climate. The bottom of a core can contain thousands of years of ice within a few centimetres, compacted by the weight of ice accumulated above it.
The New Zealand National Ice Core Research Facility in Wellington is one of only 20 or so ice-core facilities in the world. It is my role to coordinate all the jobs that are needed for our research.
In this room, we make an initial assessment of cores entering our collection. We look at the quality and integrity of the ice and measure and record the structures that we see, such as breaks, bubbles and melt layers. The ice core in the picture, which was taken in May, is a one-metre section of the Roosevelt Island Climate Evolution (RICE) core, drilled from Antarctica’s Ross Ice Shelf. We hit bedrock at 764 metres — this is the longest sample in our collection.
So far, we have dated the RICE core to 83,000 years ago, and we haven’t reached the bottom yet. We think that its last few metres, which we are investigating now, might date to the Eemian interglacial period — 127,000 to 106,000 years ago — when temperatures were several degrees warmer in Antarctica than they are today. This core could tell us a lot about Antarctic ice retreat and sea-level rise owing to climate change.
Most of our 2,300 metres of ice cores come from Antarctica, but some are from New Zealand glaciers. Those cores are precious because we’re losing our glaciers pretty quickly. Some of the locations that they were collected from don’t exist anymore.
My parents, both geologists, met in Antarctica, and I’ve always wanted to experience it. So far, I have visited Antarctica once, collecting permafrost cores, and it was amazing. People can’t stop going back if they get the opportunity. I hope to go again one day.
Nature 621, 650 (2023)
doi: https://doi.org/10.1038/d41586-023-02910-0
This story originally appeared on: Nature - Author:James Mitchell Crow
