This dataset provides stable isotope values (delta13C, delta15N) of 174 bone collagen samples collected in the western South Atlantic. Collagen was extracted from bone samples for six whale species as follows: Antarctic blue whale (n = 20), fin whale (n = 64), humpback whale (n = 46), sei whale (n = 40), southern right whale (n = 1), and sperm whale (n = 3). Bone samples were collected from ex-whaling sites across three locations in the western South Atlantic: the Falkland Islands, South Georgia, and the South Orkneys. This samples were used to estimate niche partitioning and diet specialism of whale species in the western South Atlantic. Funding: NE/L002507/1 (a NERC-Cambridge ESS Doctoral Training Partnership studentship from the Natural Environment Research Council awarded to Danielle L. Buss) and the Ecosystems component of the British Antarctic Survey Polar Science for Planet Earth Programme, funded by NERC.

This dataset comprises neodymium (Nd) isotopic compositions measured on 145 samples of aragonitic deep-sea corals from the Drake Passage of the Southern Ocean. Most of the samples were previously collected on expeditions NBP0805 and NBP1103 on the RV Nathaniel B. Palmer. The samples include glacial, deglacial and Holocene aged specimens and most are from 0-40 ka BP (thousand years before present) based on uranium-thorium dating. Neodymium isotope analyses were conducted by either thermal ionisation mass spectrometry (TIMS) or multi-collector inductively-coupled plasma mass spectrometry (MC-ICP-MS) in the MAGIC laboratories at Imperial College London by David Wilson, Torben Struve and Tina van de Flierdt. In the modern ocean, dissolved Nd isotopes are a quasi-conservative water mass tracer, while past compositions of seawater are recorded in deep-sea corals. This dataset therefore provides evidence on the proportions of Atlantic versus Pacific waters admixed in the Southern Ocean through time, which places crucial constraints on global deep water chemistry and circulation dynamics during past climate events. Funding was provided by the NERC grant NE/N001141/1. Related datasets are associated with grant NE/N003861/1. Both grants funded the project "Bridging the Timing Gap: Connecting Late Pleistocene Southern Ocean and Antarctic Climate Records".

This data product comprises 5 files, containing marine sediment pore water and solid phase leachate silicon (Si) isotopic and element concentration data, as well as benthic silica flux magnitudes derived from core incubation experiments and sediment biogenic silica contents. Samples were collected over three cruises of the Changing Arctic Ocean Seafloor (ChAOS) project summer sampling campaigns in the Barents Sea between 2017 and 2019 aboard the RRS James Clark Ross (cruises JR16006, JR17007 and JR18006). The aim of this study was to improve our mechanistic understanding of the cycling of Si within the Arctic Ocean seafloor through measurement of stable Si isotopes in the dissolved Si pool and the solid phase sources. This project was part of the Changing Arctic Ocean programme, funded by the Natural Environment Research Council (NERC) (grant no. NE/P005942/1).

During the expedition PS136 LTER HAUSGARTEN in 2023 105 samples of macrobenthic marine invertebrates and 3 samples of calanoid copepods were collected by epibenthic sledge and 28 samples of calanoid copepods were collected by Bongo and Multinet and subsequently frozen at -80 degrees Celsius for lipid and bulk stable isotope analyses. Katrin Linse, Saskia Brix, Jannifer Freer and Lydia Anastasia Schmidt collected, photographed and fixed the specimens on board. The macrobenthic invertebrates and calanoid copepods were collected to study elements of the biological lipid pump in the Arctic Ocean. The preparation and lab analyses of the lipid biomarker and stable isotope data were carried out by Rachel Jeffreys and Sabena Jane Blackbird at the University of Liverpool using Gas chromatography-mass spectrometry and an ECS8020 elemental analyser (NC Technologies) coupled to a Delta V isotope ratio mass spectrometer. Statistical analyses and interpretation of lipid biomarker and stable isotope data were carried out by Dewi Ford, Dan Mayor and Anna K. Wadsworth at the University of Exeter. The raw data files include lipid biomarker and stable isotope data for all analysed macrobenthic invertebrates and calanoid copepods, while the processed data files include all calanoid copepod data but selected macrobenthic taxa only, being Amphipoda, Decapoda, Isopoda, Mysidacea, Holothuroidea, Ophiuroidea, and Chaetognatha. The contributions of KL, JF and DJM were supported by the BIOPOLE National Capability Multicentre Round 2 funding from the Natural Environment Research Council (grant no. NE/W004933/1). DJM also received funding from OceanICU (EU Grant agreement ID: 101083922; UKRI grant reference: 10063673). SB received support via the Leibniz foundation and the ALONGate project (A Long-term Observatory of the North Atlantic Gateway to the Arctic Ocean) via grant number PS150/2023 in the program for women professors. The field work for PS136 was supported by grant no. AWI_PS136_01.

The dataset contains 3 data files. Firstly, it contains one set of stable isotope compositions expressed as delta13C, d15N, d34S values recovered from fish muscle from a variety of species captured in September 2019 across the Barents Sea as part of the joint IMR-PINRO Barents Sea Ecosystem Survey. Samples were collected by Dr Matthew Cobain and Dr Kim Vane, and isotope data analysed at the university of Southampton. A second dataset contains delta13C and delta18O compositions of fish otolith carbonate recovered from a subset of the same fish. A final sheet contains the full metadata associated with each fish sampled on the survey. All samples were processed by Dr Matthew Cobain or Prof Clive Trueman and stable isotope values determined at the University of Southampton. Funding: Project was funded under the NERC Changing Arctic Ocean project, Coldifsh (NE/R012520/1).

Glacier meltwater supplies a significant amount of silicon (Si) and iron (Fe) sourced from weathered bedrock to downstream ecosystems. However, the extent to which these essential nutrients reach the ocean is regulated by the nature of the benthic cycling of dissolved Si and Fe within fjord systems, given the rapid deposition of reactive particulate fractions at fjord heads. The dataset is used to examine the benthic cycling of the two nutrients at Patagonian fjord heads through geochemical analyses of sediment pore waters and reaction-transport modeling for Si. The dataset contains: (i) pore water redox-sensitive nitrate (NO3-) and dissolved manganese (DMn) concentration data, nutrient dissolved silicon (DSi) and iron (DFe) concentration and isotope data (delta30 Si, delta56 Fe); (ii) mild alkaline leachable (Si-Alk) and acid leachable (Si-HCl) sediment silica content and isotope data; and (iii) reaction transport model output for the benthic cycling of Si. The pore water and sediment samples were collected from four sites: SJ (48.228o S, 73.502o W, 106 m depth), SH (47.679 S, 73.715 W, 203 m depth), SP (48.179 S, 73.347 W, 248 m depth) and SB (47.787 S, 73.610 W, 151 m depth) in the Baker-Martinez Fjord Complex on the research vessel Sur-Austral in February 2017. Funded by NERC-CONICYT grant NE/P003133/1-PII20150106.

Samples of surface seawater were collected around giant icebergs A-76A (on cruise DY158) and A-23A (on cruise SD033) via the underway uncontaminated seawater systems on the RRS Discovery and RRS Sir David Attenborough respectively. Samples were collected with the motivation of identifying the biogeochemical impact of giant iceberg passage on the surrounding surface ocean. Data was collected via sensors of the uncontaminated seawater system for temperature, salinity, and chlorophyll-a concentration. Samples were taken for lab analysis upon return to the UK for dissolved macronutrients (nitrate, nitrite, phosphate, silicic acid), oxygen isotopes, and dissolved silicon isotopes. Funding has been provided by National Environment Research Council via: - C-CLEAR Doctoral Training Partnership (NE/S007164/1) - BIOPOLE (NE/W004933) - SiCLING (NE/X014819)