The westerlies whip around the Antarctic like a flywheel, with few landfalls slowing them down or getting in their way. The winds have a large part to play in directing weather systems in the Southern Hemisphere, and because of that any landmass that does sit in their path can tell a lot about prevailing conditions through history.
The Auckland Islands sit squarely in the path of the westerlies and Dr Chris Moy recently travelled there to take sediment cores, to see what they could tell him about past climate.
“The Auckland Islands are perfectly positioned in the core of the modern wind belt. They are the only land mass in that region that’s big enough to provide a range of sampling sites – we took cores from fiords, from inland lakes, and from peat bogs – each of these will have accumulated different kinds of sediment and we can tell a lot about how past climate conditions compare to those we see today.”
Chris’s research trip was funded by NZARI (New Zealand Antarctic Research institute); his collaborators are Marcus Vandergoes (GNS Science) and Matt McGlone (Landcare). Together with Otago and overseas colleagues, they will examine geochemical and paleo-biological sediments in the cores taken, and consider the implications for current weather pattern changes and longer range climate changes as well.
The extent of stratification in the fjords and in the lakes can indicate the amount of wind, the rainfall, and changes in temperature over time so the samples taken from the Auckland Islands will provide a rich load of information for Chris and his colleagues.