Last year I was told that my fieldwork in Samoa and New Caledonia was the best I’d ever experience; turns out that was a lie. This year I was fortunate enough to return to Samoa, and even more fortunate to go to the small island of Atiu in the Cook Islands. There was one very simple reason for me, along with Prof. David Sear and Dr Pete Langdon, to return to the South Pacific: we needed more sediment from the lakes on these islands. This sediment is crucial to determine how a massive band of rain – called the South Pacific Convergence Zone (SPCZ) – has moved in the past. Millions of people are dependent on the SPCZ for drinking water. Data from satellites has shown that various climatic phenomena that operate in the Pacific Ocean cause the South Pacific Convergence Zone to move. With future climate change likely to strongly affect the SPCZ and cause it to move, it is vital that we understand how it has moved in the past so that we can predict how it will move in the future.
We left London Heathrow for a somewhat gruelling 30-hour transit to Atiu to take cores from Lake Teroto. Shortly after arriving we began work obtaining wood from the local coffin maker to make our coring platform. We needed this to not only support us but to hold aluminium casing which we would be sending the corer down. It was at this point that we discovered the value of our helper Koro – a truly remarkable man. Koro is one of an increasing number of Polynesians who is navigating the Pacific on double-hulled canoes using the stars as his guide just like his ancestors did. He helped us create our coring platform; had an intuitive knowledge of what we needed help with before even asking; and climbed up coconut trees to get us fresh coconuts to drink from when working under the tropical sun. With his help we managed to obtain eight metres of sediment from the bottom of the lake: more than enough for me to work on over the remainder of my Ph.D.! What was even more exciting than the amount of mud we obtained was that we found some of it had distinct layers. This is really intriguing as layers such as those could indicate that sediment was being deposited at specific times of the year, allowing us to look at annual changes in the Lake Teroto record.
Following our week in Atiu we went on to Samoa to collect samples from Lake Lanoto’o. Having been to this lake last year we were well prepared for what was in store: red mud that got absolutely everywhere, and leeches that had a remarkable knack for getting in unusual places. It was in Samoa that we were joined by Georgia Eves – an undergraduate student who will be working on the samples obtained here for her dissertation. Georgia did a fantastic job, getting her first chance at using a corer and obtaining sediment from this fascinating lake. We managed to obtain three metres of sediment from the lake – the most that has been taken to date! Following this success we immersed ourselves in Samoan culture, visiting the local flea market for souveniers – a coconut bra or two may have been purchased… We spent our final night in a beach fale, this being a hut on a beach, and watching Samoan firedancing: a truly spectacular sight.
At times gruelling, yet always enjoyable, this fieldwork expedition was not only our most successful but definitely the most enjoyable. Here’s to hoping we can return to the South Pacific again soon.
Palaeoenvironmental Laboratory 