A biomarker perspective on dust, productivity, and sea surface temperature in the Pacific sector of the Southern Ocean

摘要: Abstract In this study, we present a new multiproxy data set of terrigenous input, marine productivity and sea surface temperature (SST) from 52 sediment samples collected along E–W transects in the Pacific sector Southern Ocean. Allochthonous input was characterized by distribution plant wax n-alkanes soil-derived branched glycerol dialkyl tetraethers (brGDGTs). 230Th-normalized burial both compound groups were highest close to potential sources Australia New Zealand are strongly related lithogenic contents (232Th), indicating common transport. Detection long-chain brGDGTs at most remote sites open ocean suggests primarily eolian transport mechanism least 110°W, i.e. prevailing westerly winds. Two independent organic SST proxies used, U 37 K ′ based on alkenones, TEX86 isoprenoid GDGTs. Both, indices show robust relationships with over range between 0.5 20 °C, likely implying different seasonal regional imprints signal. Alkenone-based estimates best reflect modern summer study area when using polar calibration Sikes et al. (1997). contrast, TEX86-derived temperatures may subsurface signal rather than surface. alkenones is Subtropical Front positively deposition material throughout area. isoGDGT south Antarctic Polar be largely controlled diatom blooms, thus high opal fluxes during austral summer.