Holocene subsurface temperature variability in the eastern Antarctic continental margin

• Main Authors: Kim, J H, Crosta, X, Willmott, V, Renssen, H, Bonnin, J, Helmke, Peer, Schouten, S, Sinninghe Damste, J S
• Format: Text
• Language: unknown
• Published: Edith Cowan University, Research Online, Perth, Western Australia 2012
• Subjects: Antarctic Circumpolar Currents; Archaeal; Climate dynamics; Continental margin; Continental shelves; Deep Water; High frequency; Holocenes; Ice sheet; Late Holocene; Sea ice extent; Sea temperature; Seasonal variability; Southern oscillation; Subsurface temperature; Temperature proxy; Temperature variability; Thermohaline circulations; Water depth; Ocean currents; Sea ice; Atmospheric pressure; Antarctic Circumpolar Wave; continental shelf; El Nino-Southern Oscillation; frequency analysis; Holocene; lipid; paleoclimate; paleoenvironment; proxy climate record; reconstruction; seasonal variation; temperature gradient; thermohaline circulation; Antarctica; Archaea; Environmental Sciences; Antarctic; The Antarctic; Antarc*; Ice Sheet
• Online Access: https://ro.ecu.edu.au/ecuworks2012/408; https://ro.ecu.edu.au/cgi/viewcontent.cgi?article=1407&context=ecuworks2012

We reconstructed subsurface (∼45-200m water depth) temperature variability in the eastern Antarctic continental margin during the late Holocene, using an archaeal lipid-based temperature proxy (TEX 86 L). 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 TEX 86 L 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 Nio 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. Copyright 2012 by the American Geophysical Union.