Abstract

GDG Ts (glycerol dialkyl glycerol tetraethers) are one of few existing quantitative temperature proxies. Although several studies have applied the TEX86 and MBT /CBT temperature indices, developed for use in oceans and soils respectively, to lake sediments there are concerns over their validity in these environments. More recently, research has led to the development of specific lake GDGT -temperature calibrations, including a global calibration using branched GDG Ts (Pearson et al., 2011; GCA . 75, 6225–6238). However, this calibration potentially over estimates temperatures in ‘colder’ environments such as Antarctica suggesting more work is needed to investigate the use of GDG Ts in these environments and that an Antarctic regional calibration may be more appropriate. We have examined relationships between GDG Ts and temperature in surface sediments from Antarctic and sub-Antarctic lakes to create a new regional calibration. Applying this new Antarctic GDGT -temperature calibration to a sediment core from Yanou Lake, King George Island, has allowed us to reconstruct past temperature changes during the Mid-Late Holocene.