This dataset documents the trends and variability in the latitude and strength of the belt of lower-atmosphere westerly winds over the Southern Ocean, referred to as the ''westerly jet''. Time series of annual mean and seasonal diagnostics are available for the period 1979-present, specifically time series of seasonal and annual mean jet latitude and strength. The diagnostics are derived from the European Centre for Medium Range Weather Forecasts (ECMWF) ERA-Interim reanalysis (for more information see www.ecmwf.int and Dee et al. (2011)), which is an observationally-constrained reconstruction of atmospheric conditions. The broad characterisation of the westerly winds into these simple diagnostics has been found to be useful for understanding long-term climate change due to contrasting drivers of change and impacts on other aspects of the climate system. This is an index of winds around the full circumference of all longitudes at Southern Hemisphere middle latitudes. The exact latitude depends on the position of the jet at any given time, but on average the jet (the core of the westerlies) is located at approximately 52 deg S.

Faecal pellets and eggs of Antarctic silverfish have been collected over the seasons using a sediment trap deployed on 1998 in Terra Nova Bay, Ross Sea, Antarctica in the frame of the National Italian Antarctic Research project (PNRA). Antarctic silverfish (ASF) accounts for over 90% of the local fish communities in the Southern Ocean costal area. Samples have been investigated in order to quantify the contribution of fish faecal pellets and eggs to the export of carbon. Funding: CLIMA project (Climatic Long-term Interactions for the Mass Balance in Antarctica) of the Italian National Program for Research in Antarctica.

This dataset presents the relative diatom abundances of 56 species/groups from the 132-120 ka interval in marine sediment core PC509 (-68.31 degN, -86.03 degE). This age interval corresponds to the peak of Marine Isotope Stage 5e (130- 116 ka). Microscope slides were prepared using a method adapted from Scherer (1994) and 300+ diatom valves were counted for each depth sample to produce the relative percentage abundance of each diatom species/group. This project was funded by the UK Natural Environment Research Council Grant NE/L002531/1

This dataset presents the relative diatom abundances of 55 species/groups from the 132-120 ka interval in marine sediment core NBP9802-04 (-64.20 degN, -170.08 degE). This age interval corresponds to the peak of Marine Isotope Stage 5e (130- 116 ka). Microscope slides were prepared using a method adapted from Scherer (1994) and 300+ diatom valves were counted for each depth sample to produce the relative percentage abundance of each diatom species/group. This project was funded by the UK Natural Environment Research Council Grant NE/L002531/1

This dataset presents the relative diatom abundances of 55 species/groups from the 132-120 ka interval in marine sediment core TPC288 (-59.14 degN, -37.96 degE). This age interval corresponds to the peak of Marine Isotope Stage 5e (130- 116 ka). Microscope slides were prepared using a method adapted from Scherer (1994) and 300+ diatom valves were counted for each depth sample to produce the relative percentage abundance of each diatom species/group. This project was funded by the UK Natural Environment Research Council Grant NE/L002531/1

This dataset presents the relative diatom abundances of 55 species/groups from the 132-120 ka interval in marine sediment core TPC290 (-55.55 degN, -45.02 degE). This age interval corresponds to the peak of Marine Isotope Stage 5e (130- 116 ka). Microscope slides were prepared using a method adapted from Scherer (1994) and 300+ diatom valves were counted for each depth sample to produce the relative percentage abundance of each diatom species/group. This project was funded by the UK Natural Environment Research Council Grant NE/L002531/1

This dataset presents the relative diatom abundances of 55 species/groups from the 132-120 ka interval in marine sediment core TPC287 (-60.31 degN, -36.65 degE). This age interval corresponds to the peak of Marine Isotope Stage 5e (130- 116 ka). Microscope slides were prepared using a method adapted from Scherer (1994) and 300+ diatom valves were counted for each depth sample to produce the relative percentage abundance of each diatom species/group. This project was funded by the UK Natural Environment Research Council Grant NE/L002531/1

This dataset presents the relative diatom abundances of 56 species/groups from the 132-120 ka interval in marine sediment core U1361A (-64.41 oN, 143.89 oE). This age interval corresponds to the peak of Marine Isotope Stage 5e (130- 116 ka). Microscope slides were prepared using a method adapted from Scherer (1994) and 300+ diatom valves were counted for each depth sample to produce the relative percentage abundance of each diatom species/group. This project was funded by the UK Natural Environment Research Council Grant NE/L002531/1

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".

Mesopelagic fish were sampled in the Scotia Sea using a 25 m2 opening and closing rectangular midwater trawl during five research cruises on RRS John Biscoe and RRS James Clark Ross. Nets sampled discrete layers, from the surface to 1000 m during austral spring, summer and autumn. The data include 17726 individual fish records from 66 taxa, the most abundant of which were myctophids of the genera Electrona, Gymnoscopelus, Krefftichthys and Protomyctophum and bathylagids (Bathylagus sp.). Length (standard length, total length or pre-anal fin length) was measured for the majority of specimens (16837), with sex and weight data also collected for many. The work was conducted as part of the BAS Ecosystems Programmes funded by the UK Natural Environment Research Council.