GSNZ Wellington branch event

The nature of the last deglaciation in New Zealand glacial records and the role of antecedent topography.

Over recent years has been intensive investigation of the timing and nature of the last deglaciation (c. 18,000 to 11,500 years ago) in New Zealand mostly using cosmogenic radionuclide chronologies from glacial limits to detail the changes in glacier positions. These events have been interpreted in terms of climatic factors, specifically temperature, though precipitation is also often considered. From these records a rapid phase of warming is inferred in the early deglaciation followed by cooling during the Antarctic Cold Reversal. Comparatively little attention has been paid to the roles of antecedent landforms and glacial sedimentology in controlling the pattern of deglaciation. Here I summarise both geological evidence and a recent modelling study to highlight an alternative deglaciation history. Implications for climatic interpretations will be considered.