Holocene sea ice and marine productivity reconstructions based on a sediment core from the northeast Scotian Shelf. The gravity core MSM101_44-3 was retieived during R/V Maria S. Merian expedition MSM101 from St. Anns Basin (45°46.651'N 58°31.967'W; 274 m water depth) in 2021 (Schneider et al., 2021). For sea-ice and productivity reconstruction of the past 10,100 years BP, biomarkers representing sea-ice algae productivity (IP25, HBI II), open-water phytoplankton productivity (dinosterol, brassicasterol), marginal ice zone (HBI III (Z), HBI III (E)), and terrigenous input (campesterol), as well as total organic carbon (TOC) and planktonic foraminifera abundances were analyzed.. The scope of the underlying study was to investigate (1) the response of sea ice to regional changes in oceanic and atmospheric conditions during the Holocene, (2) the linkage of regional Holocene sea-ice dynamics, marine productivity, and terrigenous inputs with oceanographic changes, and (3) the effects of meltwater events on sea-ice cover and primary productivity on the Scotian Shelf during the Early Holocene.

The age model of core MSM101_44-3 is based on 10 Accelerator Mass Spectrometer 14C measurements at Leibniz-Laboratory of Kiel University of mixed benthic foraminifera. It was constrained with a Bayesian Poisson-process deposition model using OxCal v4.4.4. (Ramsey, 2008. 2009) and the Marine20 dataset (Heaton et al., 2020) with a local marine reservoir offset of -86 (±66) years (McNeely et al., 2006).To determine the TOC content, sediment subsamples were treated with ethanol and hydrochloric acid and heated afterwards. The measurement was performed on an ELTRA CS-800 carbon-sulphur determinator. Reproducibility measurements (n=11) and standards were measured for quality control (σ=150 µm were normalized to the weight of sediment sample (ind/gSed).