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Relativistic electron-positron plasmas are ubiquitous in extreme astrophysical environments such as black-hole and neutron-star magnetospheres, where accretion-powered jets and pulsar winds are expected to be enriched with electron-positron pairs. Their role in the dynamics of such environments is in many cases believed to be fundamental, but their behavior differs significantly from typical electron-ion plasmas due to the matter-antimatter symmetry of the charged components. So far, our experimental inability to produce large yields of positrons in quasi-neutral beams has restricted the understanding of electron-positron pair plasmas to simple numerical and analytical studies, which are rather limited. We present the first experimental results confirming the generation of high-density, quasi-neutral, relativistic electron-positron pair beams using the 440 GeV/c beam at CERN’s Super Proton Synchrotron (SPS) accelerator. Monte Carlo simulations agree well with the experimental data and show that the characteristic scales necessary for collective plasma behavior, such as the Debye length and the collisionless skin depth, are exceeded by the measured size of the produced pair beams. Our work opens up the possibility of directly probing the microphysics of pair plasmas beyond quasi-linear evolution into regimes that are challenging to simulate or measure via astronomical observations., QC 20240701

Inductively-coupled plasma discharges are well-suited as plasma sources for experiments in fundamental high-energy density science, which require large volume and stable plasmas. For example, experiments studying particle beam-plasma instabilities and the emergence of coherent macroscopic structures - which are key for modelling emission from collisionless shocks present in many astrophysical phenomena. A meter-length, table-top, inductive radio-frequency discharge has been constructed for use in a high-energy density science experiment at CERN which will study plasma instabilities of a relativistic electron-positron beam. In this case, a large volume is necessary for the beam to remain inside the plasma as it diverges to centimeter-scale diameters during the tens-of-centimeters of propagation needed for instabilities to develop. Langmuir probe measurements of the plasma parameters show that plasma can be stably sustained in the discharge with electron densities exceeding 1011 cm-3. The discharge has been assembled using commercially-available components, making it an accessible option for commissioning at a University laboratory., QC 20230705

Relativistic electron-positron plasmas are ubiquitous in extreme astrophysical environments such as black holes and neutron star magnetospheres, where accretion-powered jets and pulsar winds are expected to be enriched with such pair plasmas. Their behaviour is quite different from typical electron-ion plasmas due to the matter-antimatter symmetry of the charged components and their role in the dynamics of such compact objects is believed to be fundamental. So far, our experimental inability to produce large yields of positrons in quasi-neutral beams has restricted the understanding of electron-positron pair plasmas to simple numerical and analytical studies which are rather limited. We present first experimental results confirming the generation of high-density, quasi-neutral, relativistic electron-positron pair beams using the 440 GeV/c beam at CERN's Super Proton Synchrotron (SPS) accelerator. The produced pair beams have a volume that fills multiple Debye spheres and are thus able to sustain collective plasma oscillations. Our work opens up the possibility of directly probing the microphysics of pair plasmas beyond quasi-linear evolution into regimes that are challenging to simulate or measure via astronomical observations., Comment: 14 pages, 8 figures

Relativistic electron-positron plasmas are ubiquitous in extreme astrophysical environments such as black holes and neutron star magnetospheres, where accretion-powered jets and pulsar winds are expected to be enriched with such pair plasmas. Their behaviour is quite different from typical electron-ion plasmas due to the matter-antimatter symmetry of the charged components and their role in the dynamics of such compact objects is believed to be fundamental. So far, our experimental inability to produce large yields of positrons in quasi-neutral beams has restricted the understanding of electron-positron pair plasmas to simple numerical and analytical studies which are rather limited. We present first experimental results confirming the generation of high-density, quasi-neutral, relativistic electron-positron pair beams using the 440 GeV/c beam at CERN's Super Proton Synchrotron (SPS) accelerator. The produced pair beams have a volume that fills multiple Debye spheres and are thus able to sustain collective plasma oscillations. Our work opens up the possibility of directly probing the microphysics of pair plasmas beyond quasi-linear evolution into regimes that are challenging to simulate or measure via astronomical observations., Comment: 14 pages, 8 figures

This report accompanies the United Kingdom Geoenergy Observatories Glasgow Surface Water Chemistry Dataset_1. The dataset comprises chemical analysis of 98 (84 samples and 14 duplicates) surface water samples that were collected monthly between February 2019 and March 2020 from water bodies proximal to the Glasgow Observatory. This baseline dataset provides valuable information on surface water chemistry prior to the operation of the Observatory, against which any future change can be assessed. This information is necessary to help understand the Observatory hydrological-hydrogeological regime; and to help de-risk similar shallow geothermal schemes in the future, provide public reassurance, and inform sustainable energy policy.

An experimental scheme is presented for generating low-divergence, ultradense, relativistic, electron-positron beams using 400 GeV/c protons available at facilities such as HiRadMat and AWAKE at CERN. Preliminary Monte Carlo and particle-in-cell simulations demonstrate the possibility of generating beams containing 10(13)-10(14) electron-positron pairs at sufficiently high densities to drive collisionless beam-plasma instabilities, which are expected to play an important role in magnetic field generation and the related radiation signatures of relativistic astrophysical phenomena. The pair beams are quasineutral, with size exceeding several skin depths in all dimensions, allowing the examination of the effect of competition between transverse and longitudinal instability modes on the growth of magnetic fields. Furthermore, the presented scheme allows for the possibility of controlling the relative density of hadrons to electron-positron pairs in the beam, making it possible to explore the parameter spaces for different astrophysical environments., QC 20210719

This report accompanies the United Kingdom Geoenergy Observatories Glasgow Surface Water Chemistry Dataset_1. The dataset comprises chemical analysis of 98 (84 samples and 14 duplicates) surface water samples that were collected monthly between February 2019 and March 2020 from water bodies proximal to the Glasgow Observatory. This baseline dataset provides valuable information on surface water chemistry prior to the operation of the Observatory, against which any future change can be assessed. This information is necessary to help understand the Observatory hydrological-hydrogeological regime; and to help de-risk similar shallow geothermal schemes in the future, provide public reassurance, and inform sustainable energy policy.

Stable isotope analyses of ostracod shells are a commonly-used proxy for palaeoenvironmental reconstruction. Although the fundamental controls on isotope composition of ostracod shells are well understood and, in some instances, quantifiable, the paleoclimatic and palaeoenvironmental interpretation of records from lake sediments depends strongly on the characteristics of individual lakes including the climatic setting, depth, volume, hydrology, aquatic vegetation and catchment properties. This is particularly important for coastal lakes where physio-chemical variations may occur on diurnal timescales. Here, we combine variations in δ18Owater, δ18Oostracod and δ13Costracod, hourly water temperature, and Mg/Caostracod inferred water temperatures (constraining calcification temperature) to improve palaeoenvironmental interpretation and provide insights into lake carbon cycle. The dataset improves understanding of complex coastal lake site systematics and downcore interpretation of stable isotopes from C. torosa, a geographically widespread brackish water ostracod. The δ18Oostracod values show a complex relationship with temperature and suggest, in most circumstances, that δ18Owater is the dominant control on δ18Oostracod. During times of fresher water, δ13Costracod increases, suggesting increasing aquatic productivity. Above a certain δ18Owater threshold however, aquatic productivity begins to decline. The interpretation of δ13Costracod in some coastal lakes, may therefore be dependent on understanding of the range of expected δ18Owater. Due to short-term (diurnal to seasonal) variations that cause large ranges in δ18Owater and δ18Oostracod, stable isotope analyses of C. torosa should be: (1) undertaken on multiple single shells (2) where carapaces are preserved, paired with trace-element/Ca analyses on the same individual; and (3) undertaken alongside a study of the modern lake system.

A previously unexplored experimental scheme is presented for generating low-divergence, ultra-dense, relativistic, electron-positron beams using 400 GeV/c protons available at facilities such as HiRadMat and AWAKE at CERN. Preliminary Monte-Carlo and Particle-in-cell simulations demonstrate the possibility of generating beams containing $10^{13}-10^{14}$ electron-positron pairs at sufficiently high densities to drive collisionless beam-plasma instabilities, which are expected to play an important role in magnetic field generation and the related radiation signatures of relativistic astrophysical phenomena. The pair beams are quasi-neutral, with size exceeding several skin-depths in all dimensions, allowing for the first time the examination of the effect of competition between transverse and longitudinal instability modes on the growth of magnetic fields. Furthermore, the presented scheme allows for the possibility of controlling the relative density of hadrons to electron-positron pairs in the beam, making it possible to explore the parameter spaces for different astrophysical environments.

A previously unexplored experimental scheme is presented for generating low-divergence, ultra-dense, relativistic, electron-positron beams using 400 GeV/c protons available at facilities such as HiRadMat and AWAKE at CERN. Preliminary Monte-Carlo and Particle-in-cell simulations demonstrate the possibility of generating beams containing $10^{13}-10^{14}$ electron-positron pairs at sufficiently high densities to drive collisionless beam-plasma instabilities, which are expected to play an important role in magnetic field generation and the related radiation signatures of relativistic astrophysical phenomena. The pair beams are quasi-neutral, with size exceeding several skin-depths in all dimensions, allowing for the first time the examination of the effect of competition between transverse and longitudinal instability modes on the growth of magnetic fields. Furthermore, the presented scheme allows for the possibility of controlling the relative density of hadrons to electron-positron pairs in the beam, making it possible to explore the parameter spaces for different astrophysical environments.

The isotope composition of seawater is an efficient method for detecting mixing between water masses. To measure long term or large scale hydrological processes at the ocean surface, it is necessary to be able to precisely compare datasets produced by different laboratories. The oxygen and hydrogen isotope (δ18O and δ2H) composition of marine waters can be measured using isotope ratio mass spectrometry (IRMS) and near-infrared laser absorption spectroscopy (LS) techniques. The IRMS and equilibration method is thought to provide results on the activity scale, while LS provides results on the concentration scale. However, the effect of dissolved seawater salts on the measurement is not sufficiently assessed and seems sometimes contradictory in the literature. For this purpose, we made artificial seawater and a pure NaCl solution from a freshwater of known isotope composition. The solutions were measured by four different laboratories allowing us to compare the two techniques. We show that minor corrections are necessary to correct seawater measurements for the salt effect and report them on the concentration scale. Interestingly, seawater measurements using LS (type Picarro) coupled to a liner are not on the concentration scale and require a correction of ~ 0.09‰ for δ18O, while the correction is relatively less significant for δ2H (~ 0.13‰). Moreover, we found for IRMS measurements that the salt effect can differ between different laboratories but seems reproducible for a given laboratory. A natural sea water sample was then analyzed by the different laboratories participating in the study. We found that applying the corrections increases the reproducibility of the isotope measurement significantly, with inter-laboratory standard deviation decreasing from 0.06 to 0.02‰ and 0.55 to 0.23‰ for δ18O and δ2H, respectively. Thus, comparing sea water datasets produced in different laboratories requires that each laboratory carries out its own calibration with artificial sea

© The Editor(s) and The Author(s) 2017. Like in much of the world, cinema screens in Australia are dominated by feature films from the US. Drawing on the Kinomatics Global Showtime Dataset, a big cultural dataset of cinema screenings, this chapter considers the diversity of films screened in Australian cinemas by examining not only the broad range of film titles on offer, but also what titles cinemagoers have practical access to, represented by films’ screen-shares. Results of this analysis reveal that despite substantial growth in the volume of first-release feature films on Australian cinema screens, for most cinema audiences, this has not translated into an increase in the diversity of films viewed, since the onus for the provision of diversity rests with smaller cinemas that do not belong to major chains.

© The Editor(s) and The Author(s) 2017. Like in much of the world, cinema screens in Australia are dominated by feature films from the US. Drawing on the Kinomatics Global Showtime Dataset, a big cultural dataset of cinema screenings, this chapter considers the diversity of films screened in Australian cinemas by examining not only the broad range of film titles on offer, but also what titles cinemagoers have practical access to, represented by films’ screen-shares. Results of this analysis reveal that despite substantial growth in the volume of first-release feature films on Australian cinema screens, for most cinema audiences, this has not translated into an increase in the diversity of films viewed, since the onus for the provision of diversity rests with smaller cinemas that do not belong to major chains.

Item does not contain fulltext, The protocols currently used for protein structure determination by nuclear magnetic resonance (NMR) depend on the determination of a large number of upper distance limits for proton-proton pairs. Typically, this task is performed manually by an experienced researcher rather than automatically by using a specific computer program. To assess whether it is indeed possible to generate in a fully automated manner NMR structures adequate for deposition in the Protein Data Bank, we gathered 10 experimental data sets with unassigned nuclear Overhauser effect spectroscopy (NOESY) peak lists for various proteins of unknown structure, computed structures for each of them using different, fully automatic programs, and compared the results to each other and to the manually solved reference structures that were not available at the time the data were provided. This constitutes a stringent "blind" assessment similar to the CASP and CAPRI initiatives. This study demonstrates the feasibility of routine, fully automated protein structure determination by NMR.

Item does not contain fulltext, The protocols currently used for protein structure determination by nuclear magnetic resonance (NMR) depend on the determination of a large number of upper distance limits for proton-proton pairs. Typically, this task is performed manually by an experienced researcher rather than automatically by using a specific computer program. To assess whether it is indeed possible to generate in a fully automated manner NMR structures adequate for deposition in the Protein Data Bank, we gathered 10 experimental data sets with unassigned nuclear Overhauser effect spectroscopy (NOESY) peak lists for various proteins of unknown structure, computed structures for each of them using different, fully automatic programs, and compared the results to each other and to the manually solved reference structures that were not available at the time the data were provided. This constitutes a stringent "blind" assessment similar to the CASP and CAPRI initiatives. This study demonstrates the feasibility of routine, fully automated protein structure determination by NMR.

Item does not contain fulltext, The protocols currently used for protein structure determination by nuclear magnetic resonance (NMR) depend on the determination of a large number of upper distance limits for proton-proton pairs. Typically, this task is performed manually by an experienced researcher rather than automatically by using a specific computer program. To assess whether it is indeed possible to generate in a fully automated manner NMR structures adequate for deposition in the Protein Data Bank, we gathered 10 experimental data sets with unassigned nuclear Overhauser effect spectroscopy (NOESY) peak lists for various proteins of unknown structure, computed structures for each of them using different, fully automatic programs, and compared the results to each other and to the manually solved reference structures that were not available at the time the data were provided. This constitutes a stringent "blind" assessment similar to the CASP and CAPRI initiatives. This study demonstrates the feasibility of routine, fully automated protein structure determination by NMR.

This paper presents an innovative method for tourist market segmentation-based on dominant movement patterns of tourists; that is, the travel sequences or patterns used by tourists most frequently. There were three steps to achieve this goal. In the first step, general log-linear models were adopted to identify the dominant movement patterns, while the second step was to discover the characteristics of the groups of tourists who travelled with these patterns. The Expectation–Maximisation algorithm was then used to partition tourist segments in terms of socio-demographic and travel behavioural variables. The third step was to select target markets based upon the earlier analysis. These methods were applied to a sample of tourists, over the period of a week, on Phillip Island, Victoria, Australia. A significant outcome of this research is that it will assist tourism organisations to identify tourism market segments and develop better tour packages and more efficient marketing strategies aligned to the characteristics of the tourists.

This paper presents an innovative method for tourist market segmentation-based on dominant movement patterns of tourists; that is, the travel sequences or patterns used by tourists most frequently. There were three steps to achieve this goal. In the first step, general log-linear models were adopted to identify the dominant movement patterns, while the second step was to discover the characteristics of the groups of tourists who travelled with these patterns. The Expectation–Maximisation algorithm was then used to partition tourist segments in terms of socio-demographic and travel behavioural variables. The third step was to select target markets based upon the earlier analysis. These methods were applied to a sample of tourists, over the period of a week, on Phillip Island, Victoria, Australia. A significant outcome of this research is that it will assist tourism organisations to identify tourism market segments and develop better tour packages and more efficient marketing strategies aligned to the characteristics of the tourists.

This paper presents an innovative method for tourist market segmentation-based on dominant movement patterns of tourists; that is, the travel sequences or patterns used by tourists most frequently. There were three steps to achieve this goal. In the first step, general log-linear models were adopted to identify the dominant movement patterns, while the second step was to discover the characteristics of the groups of tourists who travelled with these patterns. The Expectation–Maximisation algorithm was then used to partition tourist segments in terms of socio-demographic and travel behavioural variables. The third step was to select target markets based upon the earlier analysis. These methods were applied to a sample of tourists, over the period of a week, on Phillip Island, Victoria, Australia. A significant outcome of this research is that it will assist tourism organisations to identify tourism market segments and develop better tour packages and more efficient marketing strategies aligned to the characteristics of the tourists.

Wayfinding is an important aspect that should be considered by tourist park managers when allocating resources and facilities to aid tourists navigating their way through a park. This paper discusses wayfinding as a cognitive psychological process. It presents four models of the wayfinding process based on visitor levels of familiarity with the physical environment, whether the expected itinerary was pre-planned or unplanned and the spatial and temporal scales encountered in the tourist visit. The relationship between wayfinding decision-making and the roles of landmarks and cognitive map generation for each type of wayfinding process are analysed and summarised. A case study is conducted to test these four models. Wayfinding where travellers are unfamiliar with the environment but wayfinding aids are offered to travellers for a small area is the most popular type encountered in the case study. This paper highlights the need for tourist managers to understand that tourists use different methods of wayfinding and that management should provide complementary materials to assist in wayfinding. The next stage in this research will be to focus on the relationship between individual differences and wayfinding.

Data collection can become an overwhelmingtask for the simulation modeler and,indeed, can become the single most importantfactor that restricts the development and ultimateuse of that model. This chapter serves as aresource for the simulation modeler to assist indetermining what data is required and whattechniques and technologies are currently available.The chapter discusses the data requiredfor describing the spatial and-temporal movementof visitors. A review of the techniques forthe tracking and counting of visitor movements atvarious spatial scales will be undertaken andeach method will be assessed for its suitability asa mechanism for acquiring data for simulationmodeling. These techniques are summarizedassessing their advantages and disadvantagesand suitable corresponding applications.

A standard method for the analysis of carbon isotope composition of bulk organic matter (δ13Cbulk) in palaeoenvironmental and stratigraphic studies of sedimentary basins associated with hydrocarbons is suggested. This method includes the removal of interstitial hydrocarbon within the sediments, which is shown to have a negative effect on δ13C. Using the method, a δ13Cbulk trend (c. −21 to −24‰) was found within the Lower Permian Al Khlata and lower Gharif formations of Thuleilat-16 and -42 well sections, south Oman. Palaeontological and sedimentological evidence indicates considerable palaeoenvironmental change, from a cold climate lowland fern flora and upland primitive conifer flora low in the sequence, to a lowland cycad-like and upland glossopterid or other gymnospermous flora higher in the sequence. The lithologies range from glacial diamictite at the base to calcrete horizons and redbeds at the top. It is therefore likely that the δ13Cbulk trend is related to palaeoenvironmental change.

The aim of this paper is to identify suitable tracking techniques for the spatio-temporal movement behaviour of tourists in a natural environment for various applications. Several techniques at both a micro and macro scale are compared and reviewed. Each review includes a summary of advantages and disadvantages for the techniques and identifies suitable applications for each technique. Only tracking techniques will be reviewed here. The types of tracking techniques discussed includes observation and interviews, self-administered questionnaires, GPS tracking, PDA tracking and Location-Based Services (LBS), virtual questionnaires, mobile phone tracking and closed circuit television tracking. The literature review has provided guidance in choosing suitable tracking techniques for a research project that aims to model the spatio-temporal movement patterns of tourists visiting Phillip Island. This paper will provide an outline of this research project including the practical suitability of each chosen tracking technique for the Phillip Island case study.

People perceive, think, and behave differently at various spatial and temporal scales. Spatiotemporal modelling of tourist movements considers how people move about or why they exhibit certain movement behaviours. Research into spatio-temporal movements of tourists can be studied from a number of different aspects. Psychologists, for example, are concerned with understanding the cognitive aspects of why people move along particular pathways in preference to alternative pathways. Geographers and tourism researchers are more interested in how people move around particular locations and model what is observed in a visitors’ movement. However in developing simulation models that can be used to emulate tourism movement the issue of scale of movement in both time and space needs to be well understood. It is too simplistic to just apply the same model from one situation to another without thinking about the issues relating to scale. This paper discusses the issues of temporal and spatial scale for the modelling of tourist movements in terms of definition of movement, movement tracking techniques, data acquisition, data analysis, and the transition between the scales using spatio-temporal “zooming theory”.These findings have important implications when developing agent models. The paper first discusses issues relating to measuring, modelling and analysing movement behaviour at two distinct scales, namely the macro and micro level. From this initial discussion the paper then applies techniques discussed to a specific study location at Phillip Island in Victoria. The first scale examined is the macro level which covers the whole of Phillip Island. At the micro scale tourist movement behaviour is examined for a specific geographic location, the Koala Conservation Centre. Modelling the spatio-temporal movement of tourists at the macro level aims to represent the general travel patterns of a variety of tourist types. However movements of tourists modelled at the micro level reli

The oxygen and hydrogen isotope composition of waters in a small valley at Signy Island, South Orkney Islands, were monitored over three summers (1999 to 2001). These stable isotopes track water movement through the catchment, especially seasonal precipitation and snow melt. All samples fall close to the regional meteoric water line but factors other than air temperature cause year-to-year variability. Residence times are in the order of days thus the lake water provides an average of precipitation falling only a few days before, except in the winter when the lakes are effectively closed. Freezing of surface waters preserves the isotope signature of the underlying waters from the previous summer. In spring, meltwaters from winter snow are isotopically depleted having delta(18)O and deltaD as low as -13parts per thousand and -100parts per thousand (VSMOW). Ice-cover break-up in late December allows complete water column mixing. By February, the lakes are relatively enriched isotopically (delta(18)O-9parts per thousand) by summer precipitation. Precipitation isotopic composition at Halley Station, Brunt Ice Shelf, is similar, illustrating the broad-scale effects of the Weddell Sea cyclonic atmospheric circulation. These data form a useful reference data-set for the ground-based validation of atmospheric models and palaeoclimate reconstructions in this isolated sector of the South Atlantic Ocean.

The oxygen and hydrogen isotope composition of waters in a small valley at Signy Island, South Orkney Islands, were monitored over three summers (1999 to 2001). These stable isotopes track water movement through the catchment, especially seasonal precipitation and snow melt. All samples fall close to the regional meteoric water line but factors other than air temperature cause year-to-year variability. Residence times are in the order of days thus the lake water provides an average of precipitation falling only a few days before, except in the winter when the lakes are effectively closed. Freezing of surface waters preserves the isotope signature of the underlying waters from the previous summer. In spring, meltwaters from winter snow are isotopically depleted having delta(18)O and deltaD as low as -13parts per thousand and -100parts per thousand (VSMOW). Ice-cover break-up in late December allows complete water column mixing. By February, the lakes are relatively enriched isotopically (delta(18)O-9parts per thousand) by summer precipitation. Precipitation isotopic composition at Halley Station, Brunt Ice Shelf, is similar, illustrating the broad-scale effects of the Weddell Sea cyclonic atmospheric circulation. These data form a useful reference data-set for the ground-based validation of atmospheric models and palaeoclimate reconstructions in this isolated sector of the South Atlantic Ocean.

No abstract available

No abstract available

This dataset contains the oxygen isotope (O-18), dissolved oxygen, and salinity data from water samples collected from Niskin bottles on the CTD rosette on cruise JC211, February-March 2021. This cruise was formed from four separate tasks: the Polar Ocean Ecosystems Time Series (POETS) north of South Georgia; observations near iceberg A-68A southeast of South Georgia; the A23 oceanographic transect from the shelf break southeast of South Georgia, south through the eastern Scotia Sea, and into the northern Weddell Sea; and the SR1b oceanographic transect from Elephant Island off the tip of the Antarctic Peninsula to Burdwood Bank south of the Falkland Islands.

This dataset contains the oxygen isotope (O-18) and salinity data from water samples collected from Niskin bottles on the CTD rosette on cruise JR17003, the 2018 repeat of the A23 section from the shelf break southeast of South Georgia, south through the eastern Scotia Sea, and into the northern Weddell Sea. In addition to the stations on the A23 section, four stations were occupied on the West Antarctic Peninsula, one station with two casts near the South Orkney Islands, 23 stations in King Haakon Bay and on the surrounding continental shelf (one of which included O-18 samples), and one cast was made near the BAS long-term mooring site P3 northwest of South Georgia

This dataset contains the oxygen isotope (O-18), dissolved oxygen, and salinity data from water samples collected from Niskin bottles on the CTD rosette on cruise JC211, February-March 2021. This cruise was formed from four separate tasks: the Polar Ocean Ecosystems Time Series (POETS) north of South Georgia; observations near iceberg A-68A southeast of South Georgia; the A23 oceanographic transect from the shelf break southeast of South Georgia, south through the eastern Scotia Sea, and into the northern Weddell Sea; and the SR1b oceanographic transect from Elephant Island off the tip of the Antarctic Peninsula to Burdwood Bank south of the Falkland Islands.

This dataset contains the oxygen isotope (O-18) and salinity data from water samples collected from Niskin bottles on the CTD rosette on cruise JR17003, the 2018 repeat of the A23 section from the shelf break southeast of South Georgia, south through the eastern Scotia Sea, and into the northern Weddell Sea. In addition to the stations on the A23 section, four stations were occupied on the West Antarctic Peninsula, one station with two casts near the South Orkney Islands, 23 stations in King Haakon Bay and on the surrounding continental shelf (one of which included O-18 samples), and one cast was made near the BAS long-term mooring site P3 northwest of South Georgia