Publication Date:
2024-04-25
Description:
Intense seasonal productivity and carbon drawdown on the West Antarctic Peninsula (WAP) is driven by upwelling of nutrient-rich Circumpolar Deep Water (CDW) and subsequent stratification. CDW influence on the WAP is thought to have varied dramatically during the mid-Holocene, 5-7 ka. Here, we use diatom-bound nitrogen isotopes (δ15NDB), a nutrient utilization proxy, from ODP Site 1098 in Palmer Deep to study variations in the presence of CDW on sub-millennial timescales in the mid-Holocene. CDW intrusion is synchronous with atmospheric warming over Antarctica, suggesting that stronger and/or more southerly Southern Hemisphere westerlies enhanced CDW intrusion onto the WAP shelf. Our results also suggest that bulk sedimentary nitrogen isotopes (δ15Nbulk) do not track the same processes as δ15NDB at this site and that this cannot be explained by changes in diatom assemblages.
Keywords:
178-1098B; AGE; Age model, Domack et al. (2001); Carbon; Carbon, organic, total; Carbon, organic, total, standard deviation; CDW; circumpolar deep water; Depth, composite; Diatom; diatoms; Drake Passage; DRILL; Drilling/drill rig; DSDP/ODP/IODP sample designation; Element analyser CHNSO, Costech ECS 4010; Joides Resolution; Leg178; Mass spectrometer Delta V; mid-holocene; nitrogen; Nitrogen, total; Nitrogen, total, standard deviation; nitrogen isotope ratios; nitrogen isotopes; Opal, biogenic silica; Opal, biogenic silica, standard deviation; Paleoceanography; Sample code/label; sediment; Southern Ocean; Stratification; Upwelling; WAP; West Antarctic Peninsula; δ15N, bulk sediment; δ15N, bulk sediment, standard deviation; δ15N, diatom-bound organic matter; δ15N, diatom-bound organic matter, standard deviation
Type:
Dataset
Format:
text/tab-separated-values, 364 data points
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