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  • This is a scanned copy of the annual report on the scientific work undertaken at Davis Station in 1985. The report was written by J.B. Gallagher. Paraphrased from the introduction: This report describes the work undertaken at Davis from January 1985 to November 1985. Aims of the program: 1) Description of the seasonal circulation patterns within Ellis Fjord. This was done by measuring the salinity temperature profiles at selected stations down the length of the fjord, its entrance and the sea. 2) Origin, age, circulation and mixing rates of the meromictic basin. The deep waters of the meromictic basin have a salinity of approximately 1.4 the salinity of sea water. It's possible that this may be due to old sea water left behind after an isostatic uplift with subsequent concentration through evaporation. Calculation of mixing rates and description of the water circulation will explain why the basin is so stable. 3) Recent sedimentation rates within the meromictic basin. Sediment was collected from 110m for 137Cs analysis - the peak in the profile should indicate the age of that layer of sediment as 1963, during which atmospheric bomb tests released large quantities of 137Cs into the atmosphere. 4) Biogeochemistry of sulphur, iron, manganese, aluminium and carbon within the meromictic basin. The deep waters of the meromictic basin are anoxic (from 45m). This gave an ideal opportunity to study the cycling of the above redox active elements. 5) Collection and processing of water for trace element analysis and organometallics.

  • Water samples for dissolved trace metal measurements were collected from the surface (15m) down to the 1000m using an autonomous intelligent rosette system (General Ocanics, USA) specially adapted for trace metal work and deployed on a Dyneema rope. The rosette was equipped with 12x10-L Niskin-1010X bottles specially modified for trace metal water sampling. This system has been successfully deployed on the RSV Aurora Australis during voyages au0703 and au0806. Care was taken to avoid any contamination from the ship and the operating personnel. Water samplers were processed aboard under an ISO class 5 trace-metal-clean laminar flow bench in to a trace-metal-clean laboratory container on the ship's trawl deck. All transfer tubes, filtering devices and sample containers were rinsed liberally with sample before final collection. Samples were then drawn through C-Flex tubing (Cole Parmer) and filtered in-line through 0.2 micron pore-size acid-washed capsules (Pall Supor membrane, Acropak 200). Regular sampling depths were as follows: 1000m, 750m, 500m, 300m, 200m, 150m, 125m, 100m, 75m, 50m, 30m, 15m. Samples were analysed within a minute of filtration. Iron(II) was detected with the luminol method combining the experimental set-up of Hansard et al. (2009) with the chemistry as described by Croot and Laan (2002). Samples were not acidified prior to analysis and were pumped directly into the flow cell without an injection valve. Care was taken to maintain a stable light field during measurements as the luminol reagent was found to be extremely sensitive to changes in light intensity. Photons from the reaction of luminol with iron(II) were counted with a Hamamatsu photomultiplier tube housed in a light-tight box. The signal was recorded using FloZ software (GlobalFIA) and the data for each run is stored in a separate file. There is a folder for each profile that contains all the files (automatically generated by the software), which are numbered. The file numbers (e.g. sample1, sample2,...) correspond to the runs as noted in the lab book (see scans). P.L. Croot, P. Laan (2002). Analytica Chimica Acta 466: 261-273. S.P. Hansard et al. (2009). Deep-Sea Res. I 56: 1117-1129.

  • Samples were collected from the East Antarctic margin, aboard the Australian Marine National Facility R/V Investigator from January 14th to March 5th 2017 (IN2017_V01; Armand et al., 2018). This marine geoscience expedition, named the “Sabrina Sea Floor Survey”, focused notably on studying the interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles. Ten litres seawater samples were collected using a CTD rosette equipped with Niskin® bottle and filtered through a 0.45µm Millipore GWSC04510: Ground Water sampling capsule, directly into acid-cleaned 10 L polyethylene jerrycans. Samples were then acidified to pH 2 with 2 mL/L of distilled 6M HCl in a laminar flow hood. These samples were analysed for thorium isotopes (230Th and 232Th), a tracer of particle dynamics. The sample preparation was carried out in the clean lab of the Institute for Marine and Antarctic Studies (UTAS, Hobart). Seawater samples were acidified with HF (final concentration 0.6 mM, Middag et al., 2015), spiked with 10 pg of 229Th (NIST 4328C, National Institute of Standards and Technology, USA) and left to equilibrate for at least 48h. Samples were preconcentrated using Nobias® PA1L (Hitachi Technologies, Japan) cartridges, following the procedure of Pérez-Tribouillier et al., (2019). The separation and purification of thorium isotopes were performed by anion-exchange chemistry (Anderson et al., 2012). Purified Th fractions were analysed using an Element II Sector Field Inductively Coupled Plasma Mass Spectrometer (SF-ICP-MS, Thermo Fischer Scientific, Bremen, Germany) at the Central Science Laboratory (CSL) of the University of Tasmania. Sample introduction was achieved using an Aridius® II desolvating nebulizer (DSN, CETAC Technologies, USA). The capacitive guard electrode was activated to maximise signal sensitivity. Raw intensities of 230Th and 232Th were blank and mass bias corrected. Concentrations were calculated using the isotope dilution equation reported in Sargent et al., (2002). References - Anderson, R. F., Fleisher, M. Q., Robinson, L. F., Edwards, R. L., Hoff, J. A., Moran, S. B., … Francois, R. (2012). GEOTRACES intercalibration of 230Th, 232Th, 231Pa, and prospects for 10Be. Limnology and Oceanography: Methods, 10(4), 179–213. - Armand, L. K., O’Brien, P. E., Armbrecht, L., Baker, H., Caburlotto, A., Connell, T., … Young, A. (2018). Interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles (IN2017-V01): Post-survey report. ANU Research Publications - Middag, R., Séférian, R., Conway, T. M., John, S. G., Bruland, K. W., and de Baar, H. J. W. (2015). Intercomparison of dissolved trace elements at the Bermuda Atlantic Time Series station. Marine Chemistry, 177, 476–489. - Pérez-Tribouillier, H., Noble, T. L., Townsend, A. T., Bowie, A. R., and Chase, Z. (2019). Pre-concentration of thorium and neodymium isotopes using Nobias chelating resin: Method development and application to chromatographic separation. Talanta, 1–10. - Sargent, M., Harrington, C., and Harte, R. (2002). Guidelines for Achieving High Accuracy in Isotope Dilution Mass Spectrometry (IDMS). Guidelines for Achieving High Accuracy in Isotope Dilution Mass Spectrometry (IDMS). Royal Society of Chemistry.

  • Oceanographic measurements were conducted on and around the Antarctic shelf in the vicinity of the Mertz Glacier during the southern summer of 2007/2008, on Aurora Australis voyage au0803, V3 2007/2008. Data were collected as part of the CASO (oceanography) and CEAMARC (fishing) programs. The CASO program included occupation of the southern portion of the SR3 transect, plus additional transects down the slope. A total of (130) CTD vertical profile stations were taken, most to within 15 m of the bottom. Over (1400) Niskin bottle water samples were collected for the measurement of salinity, dissolved oxygen, nutrients, CFCs, dissolved inorganic carbon, alkalinity, oxygen-18, germanium, and biological parameters, using a 24 bottle rosette sampler. Full depth current profiles were collected by a lowered acoustic Doppler profiler (LADCP) attached to the rosette package, while near surface current data were collected by a ship mounted ADCP. Additional CTD profiles were taken at 2 subantarctic sites on the transit south. An array of 4 current meter and thermosalinograph moorings were deployed across a basin outflowing from the Mertz Polynya region.

  • In September 2006, twenty-three scientists from six countries attended an Experts Workshop on Bioregionalisation of the Southern Ocean held in Hobart, Australia. The workshop was hosted by the Antarctic Climate and Ecosystems Cooperative Research Centre, and WWF-Australia, and sponsored by Antarctic expedition cruise operator, Peregrine Adventures. The workshop was designed to assist with the development of methods that might be used to partition the Southern Ocean for the purposes of large-scale ecological modelling, ecosystem-based management, and consideration of marine protected areas. The aim of the workshop was to bring together scientific experts in their independent capacity to develop a 'proof of concept' for a broad-scale bioregionalisation of the Southern Ocean, using physical environmental data and satellite-measured chlorophyll concentration as the primary inputs. Issues examined during the workshop included the choice of data and extraction of relevant parameters to best capture ecological properties, the use of data appropriate for end-user applications, and the relative utility of taking a hierarchical, non-hierarchical, or mixed approach to regionalisation. The final method involved the use of a clustering procedure to classify individual sites into groups that are similar to one another within a group, and reasonably dissimilar from one group to the next, according to a selected set of parameters (e.g. depth, ice coverage, temperature). The workshop established a proof of concept for bioregionalisation of the Southern Ocean, demonstrating that this analysis can delineate bioregions that agree with expert opinion at the broad scale. Continuation of this work will be an important contribution to the achievement of a range of scientific, management and conservation objectives, including large-scale ecological modelling, ecosystem-based management and the development of an ecologically representative system of marine protected areas. This metadata record provides links to the report from that workshop, the appendices to that report, and the ArcGIS files and Matlab code used during the workshop. The report is in PDF format. The Appendices to the report are in PDF format and contain: Appendix 1: Approaches to bioregionalisation - examples presented during the workshop Antarctic Environmental Domains Analysis CCAMLR Small-Scale Management Units for the fishery Antarctic krill in the SW Atlantic Australian National Bioregionalisation: Pelagic Regionalisation Selecting Marine Protected Areas in New Zealand's EEZ Appendix 2: Technical information on approach to bioregionalisation Appendix 3: Descriptions of datasets used in the analysis Appendix 4: Results of secondary regionalisation using ice and chlorophyll data Appendix 5: Biological datasets of potential use in further bioregionalisation work Appendix 6: Details of datasets, Matlab code and ArcGIS shapefiles included on the CD The ArcGIS archive is in zip format and contains the shapefiles and other ArcGIS resources used to produce the figures in the report. The Matlab archive is in zip format and contains the Matlab code and gridded data sets used during the workshop. See the readme.txt file in this archive for more information. Description of datasets Sea surface temperature (SST) Mean annual sea surface temperatures were obtained from the NOAA Pathfinder satellite annual climatology (Casey and Cornillon 1999). This climatology was calculated over the period 1985-1997 on a global 9km grid. Monthly values were averaged to obtain an annual climatology. Casey, K.S. and P. Cornillon (1999) A comparison of satellite and in situ based sea surface temperature climatologies, J. Climate, vol. 12, no. 6, pp. 1848-1863. Bathymetry Depth data were obtained from the GEBCO digital atlas (IOC, IHO and BODC, 2003). These data give water depth in metres and are provided on a 1-minute global grid. Centenary Edition of the GEBCO Digital Atlas, published on CD-ROM on behalf of the Intergovernmental Oceanographic Commission and the International Hydrographic Organization as part of the General Bathymetric Chart of the Oceans, British Oceanographic Data Centre, Liverpool, U.K. See http://www.gebco.net and https://www.bodc.ac.uk/projects/data_management/international/gebco/ A metadata record can be obtained from: http://data.aad.gov.au/aadc/metadata/metadata_redirect.cfm?md=AMD/AU/gebco_bathy_polygons Nutrient concentrations Silicate and nitrate concentrations were obtained from the WOCE global hydrographic climatology (Gouretski and Koltermann, 2004). This climatology provides oceanographic data on a 0.5 degree regular grid on a set of 45 standard levels covering the depth range from the sea surface to 6000m. The silicate and nitrate concentrations were calculated from seawater samples collected using bottles from stationary ships. The nutrient concentrations at the 200m depth level were used here; concentrations are expressed in micro mol/kg. https://odv.awi.de/data/ocean/woce-global-hydrographic-climatology/ Gouretski, V.V., and K.P. Koltermann, 2004: WOCE Global Hydrographic Climatology. Technical Report, 35, Berichte des Bundesamtes fur Seeschifffahrt und Hydrographie. Insolation (PAR) The mean summer climatology of the photosynthetically-active radiation (PAR) at the ocean surface was obtained from satellite estimates (Frouin et al.). These PAR estimates are obtained from visible wavelengths and so are not available over cloud- or ice-covered water, or in low-light conditions including the austral winter. Hence in the sea ice zone, this climatology represents the average PAR calculated over the period for which the water was not ice-covered. https://oceancolor.gsfc.nasa.gov/cgi/l3 Robert Frouin, Bryan Franz, and Menghua Wang. Algorithm to estimate PAR from SeaWiFS data Version 1.2 - Documentation. Chlorophyll-a Mean summer surface chlorophyll-a concentrations were calculated from the SeaWiFS summer means. We used the mean of the 1998-2004 summer values. Chlorophyll concentrations are expressed in mg/m^3. https://oceancolor.gsfc.nasa.gov/cgi/l3 Sea ice We calculated the mean fraction (0-1) of the year for which the ocean was covered by at least 15% sea ice. These calculations were based on satellite-derived estimates of sea ice concentration spanning 1979-2003. http://nsidc.org/data/nsidc-0079.html Comiso, J. (1999, updated 2005). Bootstrap sea ice concentrations for NIMBUS-7 SMMR and DMSP SSM/I. Boulder, CO, USA: National Snow and Ice Data Center. Digital media. Southern Ocean Fronts These are the front positions as published by Orsi et al. (1995). Orsi A, Whitworth T, III, Nowlin WD, Jr (1995) On the meridional extent and fronts of the Antarctic Circumpolar Current. Deep-Sea Research 42:641-673 Use of these data are governed by the following conditions: 1. The data are provided for non-commercial use only. 2. Any publication derived using the datasets should acknowledge the Australian Antarctic Data Centre as having provided the data and the original source (see the relevant metadata record listed in the description below for the proper citation).

  • Taken from the accompanying report: Oceanographic measurements were collected aboard the Aurora Australis on cruise au0806 (voyage 6 2007/2008, 22nd March 2008 to 17th April 2008). This cruise completed the CASO oceanographic program begun on the CEAMARC cruise (au0803, voyage 3 2007/2008), with a full occupation of the SR3 transect between Antarctica and Tasmania. CASO program objectives were: 1. to measure changes in water mass properties and inventories throughout the full ocean depth between Australia and Antarctica along 140oE (the CLIVAR/WOCE repeat section SR3), as part of a multi-national International Polar Year program to obtain a circumpolar snapshot of the Southern Ocean in austral summer 2007-8; 2. to estimate the transport of mass, heat and other properties south of Australia, and to compare results to previous occupations of the SR3 line and other sections in the Australian sector; 3. to deploy moorings near the Adelie Depression (142-145oE) as part of a joint Australia-France-Italy program to monitor changes in the properties and flow of Adelie Land Bottom Water; 4. to identify mechanisms responsible for variability in ocean climate south of Australia. The CASO program (with a full occupation of the SR3 transect) was originally scheduled for a single cruise. The shipping schedule was re-arranged following an unexpected period in drydock, due to a problem with the ship's thrusters, and as a result the CASO program was split over the two cruises. Several of the southern stations occupied on the first cruise au0803 were repeated on the second cruise au0806, to minimise the impact on the data set of the time gap between the cruises. A total of 131 CTD vertical profile stations were taken on au0803, and 73 CTD station were taken on au0806, most to within 20 metres of the bottom. During the 2 cruises, over 2900 Niskin bottle water samples were collected for the measurement of salinity, dissolved oxygen, nutrients (phosphate, nitrate+nitrite and silicate), 18O, CFC's, dissolved inorganic carbon, alkalinity, 14C, dissolved organic carbon, density (i.e. analysis of the effect of water composition on water density), germanium/silica/boron isotopes, trace metals, neodymium, chlorophyll-a, cell counts, pigments, genetic analyses, and other biological parameters, using a 24 bottle rosette sampler. Full depth current profiles were collected by an LADCP attached to the CTD package, while upper water column current profile data were collected by a ship mounted ADCP. Data were also collected by the array of ship's underway sensors. This report describes the processing/calibration of the CTD data, and details the data quality. An offset correction is derived for the underway sea surface temperature and salinity data, by comparison with near surface CTD data. CTD station positions are shown in Figures 1 and 2, while CTD station information is summarised in Table 1. Mooring and drifter deployments/recoveries are summarised in Table 14. Mooring data from the Adelie Depression deployments are discussed in the mooring data reports Rosenberg (unpublished report, 2009) and Meijers (unpublished report, 2009). Further cruise itinerary/summary details can be found in the voyage leader reports (Australian Antarctic Division unpublished reports: Riddle, V3 2007/08 VL report; Rintoul, V6 2007/08 VL report). Hydrochemistry and CFC cruise reports are in Appendix 1 and Appendix 2. Details about the data are available in a readme file and a full report in the download file.

  • From the abstract and introduction of ANARE Research Notes 44 - ADBEX I cruise to the Prydz Bay region, 1982: nutrient data. Nitrate, phosphate and silicate concentrations obtained during the ADBEX I cruise to the Prydz Bay region in November and December 1982 are plotted with depth and the raw data are tabulated. Location of the sampling stations and the average concentration of each nutrient in the top 100 m of the water column is mapped. The ADBEX I (Antarctic Division BIOMASS Experiment) cruise is part of a long-term, national program of field surveys aimed at fulfilling the objectives of the BIOMASS (Biological Investigation of Marine Antarctic Systems and Stocks) program. The ADBEX I cruise on MV Nella Dan to the Prydz Bay region between 19 November and 17 December 1982, is the second Antarctic Division cruise to contribute to BIOMASS, the first being FIBEX (First International Biomass Experiment) in 1981. Nutrient data were collected at twenty-eight of the seventy-nine hydrographic stations to provide information for the interpretation of phytoplankton distribution and abundance. The sampling locations and depths were not selected, therefore, on the basis of nutrient-related considerations. The concentration of nitrate, phosphate and silicate is plotted to 600 m for each station and where casts were much deeper or much shallower, a second plot is shown. To show water column structure at the time of sampling, sigma-t values were also plotted, unless data for a cast were unavailable. In addition to the depth profiles, the average concentration to 100 m of each nutrient species is mapped to give a first-order approximation of the horizontal pattern of nutrient distribution in the upper layers.

  • A register of all voyages that contribute to the science of the Australian Antarctic Programme. It includes voyages that opportunistically collect marine data while underway. Details have been gleaned from historic paper records, publications, voyage situation reports and reports from marine science cruises. Products linked to each voyage include a map, voyage schedule and a list of any science related activities on the voyage. The application links to various external resources within the Antarctic Division such as daily shipping reports, passenger lists and various sets of data. NOTE - Support for this application was put "on hold" after the 2013/2014 season. Hence, only voyages up until that season are included in the database. This decision may be revisited at some time in the future.

  • Preliminary Metadata record for data expected from ASAC Project 1343 See the link below for public details on this project. Comparative study of the processes controlling carbon export in Southern Ocean environments characterised by a different hydrodynamical and ecological functioning. Work on this project was carried out on Voyage 3 of the Aurora Australis (CLIVAR) of the 2001 and 2002 season. Work at sea target sampling sites were the 8 'particle stations' along the CLIVAR SR3 repeat transect: the SAZ at 47 degrees and 49 degrees S; the SAF at 51 degrees S; the PFZ at 54 degrees S; the IPFZ at 57 degrees S; the SPZ at 59 degrees and 61 degrees S; the SACCF at 63 degrees S and the SSIZ at 64 degrees S. Some of these (64 degrees, 61 degrees and 51 degrees S) were sampled again on the way back to assess temporal evolution. All proxy studies (new production; Ba; delta30Si; 234Th-deficit) were done at each particle station but not necessarily on the same CTD casts. New production assessment Surface water (at 5, 25, 50 and 70m) was sampled with the CTD rosette at all particle stations. Different aliquots of 1L seawater were spiked with 15N-nitrate, 15N-ammonium or 15N-urea. All samples were spiked with 13C-bicarbonate; the latter in order to assess net primary production rates. Incubations (12 H) were done in a thermo stated algal cabinet, using appropriate neutral density screens for samples from depths below 5m. The samples were submitted to a constant light flux of 0.7x10power16 quanta/cm2/sec. Furthermore, samples from 5m depth were amended with increasing doses of ammonium (+0.1 micro M; +0.25 micro M; +0.5 micro M and +1 micro M) having natural 15N/14N abundance to assess susceptibility of N-uptake (ammonium, nitrate, urea) to ammonium. Similar experiments were run for three iron amended and control cultures in collaboration with Pete Sedwick, Dave Hutchins and Phil Boyd. Analysis of ammonium related to the incubation work was done on board by colorimetry. As a side product we obtained ammonium profiles at all particle stations and also six shallow CTD's in the southern part of the transect (greater than 61 degrees S). Suspended particle sampling for trace element analysis and isotopic composition of Si For biogenic-Ba was also carried out. Typically 14 depths were sampled between the surface and 1000m. On board filtration was performed on Nuclepore membranes. These were dried (60 degrees C) and stored for analysis in the shore-based lab. Occasionally, we also sampled large particles - size fractions (greater than 70 micro m and 20 less than 70 micro m) - from the upper 150m for Ba, using the bow pump system of Tom Trull. Ba and Sr incubations on large settling particles sampled with the Snatcher were also performed at 5 particle stations. For delta30Si, all 24 depths of the deep CTD casts at the particle stations 1 to 8 were sampled. Filtered seawater and suspended matter filtered on Nuclepore membranes (dried at 60 degrees C) were saved for later analysis in the home based laboratory. 234Th work - we refer to the report by Ken Buesseler for the major part of this work. In addition we performed some work using the 'Snatcher' Large Volume sampler and sedimentation column. Total 234Th deficit and 234Th activity on particles and solution was assessed at T0 and T4 H after return of the sampling device on board, in an attempt to construct the 234Th mass balance and eventually get at the settling speed (and flux) of 234Th carrying particles. These analyses went together with flow cytometry analyses (collaboration with Clive Crossley) to check for sedimentation by (fluorescent) particles and also with POC and biogenic silica in order to determine the elemental ratios of suspended and sinking particles. Flow cytometer results did not indicate there was significant sedimentation of life cells going on at this time of the year. Dissolved Ba Seawater samples were taken at all depths sampled by deep CTD's during the southward transect. Samples were acidified and kept for later analysis of dissolved barium by isotope dilution ICP-MS. Comparison of the dissolved Ba distribution along the transect with the one reconstructed through a multiple end-member mixing model will help understanding of the relative contribution of in-situ processes (uptake, dissolution) versus conservative mixing, thus improving our understanding of the oceanic Ba biogeochemistry. Analysis New production. Isotope ratio analysis of the 15N and 13C spiked natural plankton samples will be conducted in the home lab., using emission spectrometry and mass spectrometry. Mass balance calculations will allow assessing relative importance of new production as well as the fraction of new production that is in the particulate form and represents the potential for export. Ba and trace elements. Suspended matter samples will be acid digested (HNO3, HCl, HF) and analysed per ICP-MS and ICP-AES for contents of Ba, Ca, Sr, Al, Fe, Mn, Th, U, REE, Ti. The vertical concentration profiles will inform on the latitudinal and temporal variability of the biogeochemical control processes between SAZ, PFZ, ACC and SSIZ subsystems. For the sites with sediment trap deployments, particulate trace element distributions in the water column will be compared with trace element composition of fast settling particles intercepted by the traps. Ba-uptake / barite formation. Isotope ratio analysis (135Ba/138Ba; 86Sr/87Sr) of suspended matter incubated after spiking with 135Ba and 86Sr will be analysed by ICP-MS to investigate on the barite formation process. Abundance and type of barite crystals will be studied by SEM-EMP (mapping + photographs). delta30Si, In the home based lab. particle samples will be extracted using base (NaOH). Silicates in filtered seawater will be precipitated and analysed using a multi collector ICP-sectorial Mass Spectrometer (MC-ICP-MS) once this new method is set up. 234Th. Total, particulate and dissolved 234Th measurements were performed on board using low beta counters. Background (after 6 months decay) and chemical yields will be measured at Ken Buesseler's lab (WHOI, USA), using beta counters and ICP-MS respectively. The worksheets contained in the excel spreadsheet are: Phyo biomass New production and cell counts Particulate barium Dissolved barium d29Si isotope signature of dissolved silicic acid The fields in this dataset are: Carbon Seawater CLIVAR temperature pressure salinity depth barium latitude longitude oxygen silicate phophate nitrate flagellates diatoms picoplankton plankton urea ammonia coccolithophores

  • During the K-Axis marine voyage from mid Jan-late Feb 2016, a diverse range of sampling techniques were employed to collect specimens and data. Each sampling event was recorded by scientists and technical support staff in a logbook that was kept in the operations room on board the Aurora Australis. This is a PDF of the scanned original document, compiled on paper during the voyage. event_number: A unique event identifier in the log, in the order that the events were written down (usually but not always chronologically) event_type: The code defined and used by each research project to identify the types of equipment deployed or samples collected for an event. event_type_prefix: A non-mandatory prefix field used by some research projects to identify the type of an event event_type_number: A sequential number or alphanumeric-number combination defined and used by each research project to identify unique equipment deployment or sample collection events station_number: A universal (voyage-wide) station number used across all projects to identify a nominal lat/lon position defined during voyage planning leg: A nominally straight-line section of the voyage track defined during voyage planning. The voyage track was planned as a series of roughly N-S and E-W transects that intersected in some locations. Legs start at a station and continue through more stations to a vertex-station which is the start of the next leg. Legs are numbered consecutively. waypoint: A GPS waypoint used by Aurora Australis crew, AAD science technical support and researchers to identify target lat/lon positions in the voyage. Some waypoints correspond with station numbers. start_date_utc: The start date of the event in UTC start_time_utc: The start time of the event in UTC start_lat_deg: The latitude (whole degrees) of the vessel at the beginning of the event start_lat_min: The latitude (minutes) of the vessel at the beginning of the event start_lat_dec_deg: The latitude (decimal degrees) of the vessel at the beginning of the event start_lon_deg: The longitude (whole degrees) of the vessel at the beginning of the event start_lon_min: The longitude (minutes) of the vessel at the beginning of the event start_lon_dec_deg: The longitude (decimal degrees) of the vessel at the beginning of the event end_date_utc: The end date of the event in UTC end_time_utc: The end time of the event in UTC end_lat_deg: The latitude (whole degrees) of the vessel at the end of the event end_lat_min: The latitude (minutes) of the vessel at the end of the event end_lat_dec_deg: The latitude (decimal degrees) of the vessel at the end of the event end_lon_deg: The longitude (whole degrees) of the vessel at the end of the event end_lon_min: The longitude (minutes) of the vessel at the end of the event end_lon_dec_deg: The longitude (decimal degrees) of the vessel at the end of the event remarks: Comments/remarks written by researchers when completing the paper log