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  • Establishing lichenometric ages for nineteenth- and twentieth-century glacier fluctuations on South Georgia (South Atlantic)
  • Antarctica ; Climatic variability ; Cold area ; Dating ; Glacier fluctuation ; Island ; Lichenometry ; Little ice age ; Moraine ; Nineteenth Century ; Twentieth Century
  • As part of a reconnaissance study in Prince Olav Harbour (POH), South Georgia, the AA. measured the size of lichens (Rhizocarpon) on ice-free moraine ridges around 2 small mountain cirques. Their aims were twofold : first, to provide age estimates
  • for lichen colonization, and hence, deglaciation of the moraine ridges, and second, to examine the potential of applying lichenometry more widely to provide deglacial age constraints on South Georgia. The AA. use long-term Rhizocarpon lichen growth rates from
  • recent studies on sub-Antarctic Islands and the western Antarctic Peninsula to calculate likely age estimates. Results and discussion.
  • to predict the age of a dated surface in southeast Iceland. Results and discussion about a possible alternative method of studying the growth rate of lichens.
  • studies based on these 5 lichen dating curves with tree-ring based glacier histories from southern Alaska shows generally good agreement, albeit with greater scatter in the lichen-based ages. Cosmogenic surface-exposure dating of Holocene moraines has
  • , and that bomb-C 14 analysis alone cannot be used to determine lichen age or absolute growth rates in this lichen species.
  • -age estimates of these moraines in the context of other climatic proxies in the region.