We reconstructed subsurface (~45-200 m water depth) temperature variability in the eastern Antarctic continental margin during the late Holocene, using an archaeal lipid-based temperature proxy (TEX86L). Our results reveal that subsurface temperature changes were probably positively coupled to the variability of warmer, nutrient-rich Modified Circumpolar Deep Water (MCDW, deep water of the Antarctic circumpolar current) intrusion onto the continental shelf. The TEX86L record, in combination with previously published climatic records, indicates that this coupling was probably related to the thermohaline circulation, seasonal variability in sea ice extent, sea temperature, and wind associated with high frequency climate dynamics at low-latitudes such as internal El Niño Southern Oscillation (ENSO). This in turn suggests a linkage between centennial ENSO-like variability at low-latitudes and intrusion variability of MCDW into the eastern Antarctic continental shelf, which might have further impact on ice sheet evolution.
Data were obtained within the framework of the ERC PACEMAKER project (Grant number: 226600) and ANR CLIMICE (ANR-08-CEXC-012-01), provided for the data compilation of the Past4Future Project.
Supplement to: Kim, Jung-Hyun; Crosta, Xavier; Willmott, Verónica; Renssen, Hans; Bonnin, Jerome; Helmke, Peer; Schouten, Stefan; Sinninghe Damsté, Jaap S (2012): Holocene subsurface temperature variability in the eastern Antarctic continental margin. Geophysical Research Letters, 39, L06705