Publication Date:
2023-07-09
Description:
In the light of rapidly diminishing sea ice cover in the Arctic during the present atmospheric warming, it is imperative to study the distribution of sea ice in the past in relation to rapid climate change. Here we focus on glacial millennial scale climatic events (Dansgaard/Oeschger events) using the new sea ice proxy IP25 in combination with phytoplankton proxy data and quantification of diatom species in a record from the SE Norwegian Sea. We demonstrate that expansion and retreat of sea ice varied consistently in pace with the rapid climate changes 90 ka to present, and with this present the first IP25 sea ice proxy record resolving the D/O cyclicity going back in time into Marine Isotope Stage 5a. Sea ice retreated abruptly at the start of warm interstadials, but spread rapidly during the cooling phase of the interstadials and became near-perennial and perennial during cold stadials and Heinrich events, respectively. Low salinity surface water and the sea ice edge spread to the Greenland-Scotland Ridge, and during the largest Heinrich events, probably far into the Atlantic Ocean.
Keywords:
2,6,10,14-Tetramethyl-7-(3-methylpent-4-enyl)pentadecane, per unit mass total organic carbon; 2,6,10,14-Tetramethyl-7-(3-methylpent-4-enyl)pentadecane per unit sediment mass; 24-Methylcholesta-5,22E-dien-3beta-ol, per unit mass total organic carbon; 24-Methylcholesta-5,22E-dien-3beta-ol per unit sediment mass; 4alpha,23,24-Trimethyl-5alpha-cholest-22E-en-3beta-ol, per unit mass total organic carbon; 4alpha,23,24-Trimethyl-5alpha-cholest-22E-en-3beta-ol per unit sediment mass; Accumulation rate, diatoms; AGE; Calculated; Carbon, organic, total; Counting, diatoms; DEPTH, sediment/rock; Diatoms, total, per unit sediment mass; Element analyser CHN, LECO CNS 2000; Fragilariopsis oceanica; Gas chromatography; Jan Mayen; JM11; JM11-FI-19PC; Magnetic susceptibility, volume; Mass spectrometry; Neogloboquadrina pachyderma sinistral, δ18O; Norwegian Sea; PC; Phytoplankton biomarker Brassicasterol IP25 index; Phytoplankton biomarker Dinosterol IP25 index; Piston corer; Sedimentation rate; Thalassiosira oestrupii; δ13C
Type:
Dataset
Format:
text/tab-separated-values, 3773 data points
Permalink
