Unique slices of time: Salvaging New Zealand sub-fossil kauri (Agathis australis) that span the termination of the Last Glacial Period

Lead Research Organisation: UNIVERSITY OF EXETER
Department Name: Geography

Abstract

The end of the last glacial period provides valuable insights into the mechanisms of abrupt and extreme climatic and environmental change. Unfortunately, although there are numerous ice, marine and terrestrial records from around the world that span this period, precise comparisons are hampered by the absence of a robust terrestrial calibration before 12,590 years ago. We have identified a new site, Towai Farm, New Zealand, where we have previously recovered 4 sub-fossil trees that all fall within the termination of the last glacial during the Younger Dryas Chronozone, a period of known abrupt and extreme climate change. With the ongoing drought in Northland (currently estimated to cost NZ$300 million in lost agricultural production), the greatly lowered water table has exposed a further 12 trees that are in the process of being extracted for sale to timber merchants. These kauri are of vast proportions and almost perfectly preserved; individual trees measure up to 2.2 metres across, suggesting they lived up to 2000 years. Within this precious archive is an annual record of changing atmospheric radiocarbon levels and past climate. The age and timespan of these trees are unique in the world and therefore a resource of international significance. This Urgency Award is required to salvage and archive the Towai Farm kauri for the wider scientific community before it is lost forever.