Metadata record for data from ASAC Project 2720 See the link below for public details on this project. The overall objective is to characterise Southern Ocean marine ecosystems, their influence on carbon dioxide exchange with the atmosphere and the deep ocean, and their sensitivity to past and future global change including climate warming, ocean stratification, and ocean ... acidification from anthropogenic CO2 emissions. In particular we plan to take advantage of naturally-occurring, persistent, zonal variations in Southern Ocean primary production and biomass in the Australian Sector to investigate the effects of iron addition from natural sources, and CO2 addition from anthropogenic sources, on Southern Ocean plankton communities of differing initial structure and composition. These samples were collected on the SAZ-SENSE scientific voyage of the Australian Antarctic Program (Voyage 3 of the Aurora Australis, 2006-2007 season). SAZ-SENSE VOYAGE AU0703 ADCP DATA * The complete ADCP data for cruise au0703 are in the files: au070301.cny (ascii format) a0703dop.mat (matlab format) * The "on station" ADCP data (specifically, the data for which the ship speed was less than or equal to 0.35 m/s) are in the files: au0703_slow35.cny (ascii format) a0703dop_slow35.mat (matlab format) * The file bindep.dat shows the water depths (in metres) that correspond to the centre of each vertical bin. * The data are 30 minute averages. Each 30 minute averaging period starts from the time indicated. (so, e.g., an ensemble with time 120000 is the average from 120000 to 123000). * ADCP currents are absolute - i.e. ship's motion has been subtracted out. * Note that the top few bins can have bad data from water dragged along by the ship. * Beware of data when the ship is underway - it's often suspect. * Important data quality information can be found in the data report referenced above. * The figure a0703difship30.eps shows the speed difference between vertical bin 2 and all other bins, where the data have been divided up into different speed classes for ship speed. The apparent vertical shear for bins ~1-10, and below bin ~40, is an error, possibly due to acoustic ringing from an air/water interface in the seachest. Data where ship speed is 0 to 1 m/s does not show this error.

These data were collected by 8 EM-APEX profiling floats, which are a sophisticated version of the standard Argo float. They measure temperature, salinity and pressure, as for standard Argo. They also use electromagnetic techniques to measure horizontal velocity. The floats were deployed across the northern Kerguelen Platueau in November 2008, and drifted eastward with the Antarctic Circumpolar Current as they profiled between the surface and 1600 dbar. They transmitted data through the Iridium satellite system and continued to profile eastward until their batteries failed. The range of latitudes covered is approx. 40S-50S, and longitudes 65E-90E. Although most of the data is in the longitude band 65E-78E. The temporal range of the data is Nov 2008 to approx. Sep 2009. The file "emapex_final.mat" contains the quality-controlled and calibrated data from 8 EM-APEX profiling floats deployed across the northern Kerguelen Plateau during the Southern Ocean Finestructure (SOFine) experiment aboard the U.K. RRS James Cook, Cruise 29, 1st Nov-22nd Dec 2008, Cape Town to Cape Town. Funding for the EM-APEX component of the experiment was from the Australian Research Council Discovery Project DP0877098 (N. Bindoff, H. Phillips and S. Rintoul). The Australian Antarctic Division provided subantarctic clothing for Bindoff and Phillips under AAS project #3002 (H. Phillips and N. Bindoff). AAS project #3228 (N. Bindoff and H. Phillips) provided $27,000 for salary support for a research assistant to work on analysis of the data and publication of a manuscript. Significant in-kind support was provided by CSIRO Marine and Atmospheric Research for the EM-APEX component. Details of the shipboard operations and deployment of the EM-APEX floats can be found in the document "emapex_deployment_report.pdf". The complete voyage report is available from h.e.phillips@utas.edu.au. It may be cited as Naveira Garabato, A.; Bindoff, N.; Phillips, H.; Polzin, K.; Sloyan, B.; Stevens, D. and Waterman, S. RRS James Cook Cruise 29, 01 Nov - 22 Dec 2008. SOFine Cruise Report: Southern Ocean Finestructure National Oceanography Centre, Southampton, 2009 See the download file for more information, which contains a data report and a data description file as well as the data.

Metadata record for data from ASAC Project 2784 See the link below for public details on this project. This project utilised an existing 55 year model reanalysis (SODA) - so no new models were developed. The methodologies/data used are described in the referenced publications. Modelling investigations of the shoaling of iron-rich upper circumpolar deep water (UCDW) and its role in the regulation of primary production at 60-65S. Taken from the project application: We intend to utilise a number of existing data sources to study the factors leading to spatiotemporal variability in the upwelling of iron-rich UCDW in the 60-65S zone, which, as discussed above, seems critical to regional ecosystem function, and the carbon and sulphur budgets of the SO. As sea-ice extent appears to have declined in the Southern Ocean since the 1950s (Curran et al., 2003) it will also be extremely interesting to examine whether this has had any affect on the upwelling of the UCDW. Given the restricted spatial domain of in situ field data in the Southern Ocean, satellite products provide us with one of the few means to investigate coherent variability over large spatial and temporal scales. This study takes advantage of our previous AAS funded work (Projects: 2584, 2319), where we have gained considerable experience in the coupling of biogeochemical and climate models and where we have already assembled satellite data sets on wind speed, sea-ice, SST, aerosols and chlorophyll-a concentration. This previous experience will allow us to examine the relationship between the physical forcings, the dynamics of the UCDW and the biological response on seasonal and interannual timescales over the period 1950-2000. The key scientific questions we seek to answer include: - What is the range of interannual and interdecadal variability in upwelling of the UCDW and how does this relate to variability in primary production? - Is there a connection between interannual/decadal variability in sea-ice extent and the strength or location of upwelling of UCDW and hence the character of regional primary production? - Is there a relation between the seasonal production of DMS and associated S-aerosols and the dynamics of UCDW? Details from previous years are available for download from the provided URL. Taken from the 2009-2010 Progress Report: Progress against objectives: This three-year project has been investigating the nexus between the large-scale meridional circulation patterns in the SO, in particular UCDW upwelling, and concomitant iron delivery to surface waters and the phytoplankton. Key Scientific Questions to be considered by the project What is the range of interannual and inter-decadal variability in upwelling of the UCDW and how does this relate to variability in primary production? This study initially focussed on the Australian region of the Southern Ocean (110-160 degrees S, 40-70 degrees E) and the physical oceanographic data for the project came from monthly Simple Ocean Data Assimilation (SODA) reanalysis data, which covers the period 1958-2007 over the global ocean. Decadal-scale trends in upper ocean structure and meridional circulation were analysed, including the upwelling of nutrient-rich UCDW, and these results were initially documented in presentation (3) below and will shortly be published in publication (1) listed below. The project identified UCDW in SODA using temperature and density criteria and, using this, a number of variables were developed to characterise UCDW and its upwelling: UCDW vertical velocity, temperature, density and salinity, UCDW top depth (the shallowest depth at which UCDW is found) and UCDW southern-most position. Climatological values were found for each of the 5-degree strips in the sector and, in addition, trends were found over the period 1958-2005. Later work involved comparing these results with those of two more Southern Ocean sectors - one in the Pacific (130-80 degrees W) and one in the Indian Ocean (20-60 degrees E). These results were presented at the AMOS conference in January 2010 (see Presentation (1) below) and are also the subject of a paper in the Proceedings of that conference (see Publication (2) below). It was found that during 1958-2005: (1) UCDW top depth varies seasonally, peaking in March, and displays considerable interannual variability; (2) Climatological properties for UCDW variables such as temperature, vertical velocity and upwelling depth vary between the three ocean sectors, as do trends (1958-2005) in the UCDW variables; (3) UCDW vertical velocity (ie. upwelling) appears to be increasing with time in most intermediate and deep waters of the three ocean sectors; (4) UCDW temperature is increasing in intermediate waters in the Pacific sector, at all depths in the Indian sector and at shallow depths in the Australian sector, but is decreasing in intermediate and deep waters in the Australian sector; (5) UCDW southern-most position is moving south in the Australian and Pacific sectors; (6) UCDW is upwelling closer to the surface in the Australian and Indian sectors and, in the case of the Australian sector, this translates into an increase in the number of times that UCDW can be detected in the mixed layer (a finding of possible importance for primary production); (7) UCDW trends in the Australian sector do not appear to be affected by trends in the winds, but by forcings acting on longer than decadal time-scales. This is not the case, however, for the other two sectors, leading to the speculation that these variables may be affected by the re-entry into UCDW of recirculated waters from the Indian and Pacific Oceans, which may themselves be affected by winds. (8) The Australian sector of the SO has been shown to have its own unique characteristics, distinct from either the Pacific or Indian sectors. More recent work has involved looking at the initial Australian sector considered above, over the period of the high resolution satellite data capture era (1997-2007), with the aim of using satellite data on chlorophyll a (chl a), sea-ice concentration and photosynthetically active radiation (PAR), as well as modelled data for primary production (PP), in addition to the reanalysis data, to look at factors that influence chl a and PP over that time period. Initial work was presented at the AMOS conference in January 2009 (see Presentation (2) below) and final work is reported in Publication (3) listed below, which is almost ready for submission. It was found that in the Australian sector during 1997-2007: (1) The most important controls on chl a in spring are sea-ice concentration and PAR in the southern-most zones (and mixed layer depth, SST, stratification and PAR in zones further north); (2) The situation is more complex in summer, especially in the southern-most zones (the areas of highest production, excluding the most northerly zone near Tasmania). In particular, in the 60-65 degrees S zone in summer, a variety of inter-acting controls affect chl a (and PP), including SST, stratification and UCDW top depth; (3) The number of times that UCDW is detected in the mixed layer is decreasing in summer during 1997-2007; (4) It is difficult to identify trends that are statistically significant over such a short time period and trends that are found are often opposite in sign to those for 1958-2005 and up to an order of magnitude larger. Thus care needs to be taken with trends found for chl a, PP and hydrodynamic variables over the short period of the satellite era, since there is a large range of such ten-year trends in the period 1958-2005. Is there a connection between interannual/decadal variability in sea-ice extent and the strength or location of upwelling of UCDW and hence the character of regional primary production? Given that UCDW upwells south of the Polar Front and no further south than the Southern Boundary of the ACC (approximately 65 degrees S in this sector), then UCDW, as identified here in its pure form, is not able to affect the 65-70 degrees S zone (although this is possible in its modified form, which is not studied here). It was found that, for the period 1997-2007 in the Australian sector of the SO, the southern-most position of UCDW is not correlated with sea-ice concentration, but that there are weak (90% level) correlations in 60-65 degrees S between UCDW top depth and sea-ice concentration in autumn (positive), the temperature of UCDW and sea-ice concentration in summer (positive) and northward Ekman transport and sea-ice concentration in summer (negative). It was found that, for 1997-2007 in the Australian sector of the SO, sea-ice concentration has a significant (inverse) relationship with chl a and PP in 60-70 degrees S in spring and 65-70 degrees S in summer. In addition, UCDW top depth and northward Ekman transport (ie. how quickly the UCDW nutrients are transported northwards and away from the zone) have a minor effect on chl a in 60-65 degrees S in summer.

In situ Lagrangian drifter positions were collected from nine expendable sea-ice buoys. Positions were collected by GPS receivers aboard each buoy and relayed via the CLS Argos satellite data system. The scientific proposal for this project was based on the deployment of two meso-scale buoy arrays over the continental shelf break in the SIPEX 2012 experimental region. Resolving of ice motion over the continental shelf and the shelf break is expected to provide crucial information on sea-ice deformation and ice strength. However, due to the unfavourable cruise track and also due to operational issues with helicopter support, it was not possible to deploy any of the meso-scale buoy arrays. Instead buoys were deployed to resolve ice deformation within the wider SIPEX 2012 region. Position data are available hourly from most buoys. CLS Argos transmitted data suffer from a data transmission blackspot just prior to local none, when there will be no data available. Data processing will be carried out as described in Heil et al. [2008] The dataset is build from ASCII files for each buoy with time stamps and observed latitude and longitude. The format (by column [C] for each file is as following: C1: Program ID C2: Buoy ID C3: Year C4: Month C5: Day C6: Hour C7: Minute C8: Second C9: Day-of-year C10: Lat (degN) C11: Lon (degE)

A 600KHz Teledyne RDI Workhorse Sentinel ADCP was deployed through a 10inch auger hole, flush with the base of the ice, looking downwards. At ice stations 2, 3, and 4 the deployment locations was Ridge site 1, the ridge site closest to the ship. At ice station 7 there were 4 different deployment locations: - Transducer Hole A, by active ridge on 6th October 2012; - Trace Metal / Bio Site; - 100m Core site of ice-physics transect; - Transducer Hole A, re-drilled on 7th October 2012. Length of deployment varies from stations to station and was limited by AUV operations, when our ADCP was switched off. Files contain the data collected in raw format. This format can be read by Teledyne WinSC software. Data files are stored in folders by ice station (see below).

Acoustic Doppler current profiler (ADCP) measurements from a hull mounted 150 kHz narrow band ADCP unit were collected in the Southern Ocean from 1994 to 1999, on the following cruises: au9404, au9501, au9604, au9601, au9701, au9706, au9807 and au9901. The fields in this dataset are: Currents bottom depth cruise number ship speed time velocity GPS

Metadata record for data from ASAC Project 2320 See the link below for public details on this project. ---- Public Summary from Project---- The project explores the extent to, and the manner in, which the El Nino-Southern Oscillation (ENSO) phenomenon influences the Antarctic and subantarctic region, particularly in the Pacific sector. Recent changes in Antarctic climate will be assessed in light of changes in ENSO activity. In this project, the NCEP reanalysis datasets were sourced from: NOAA/National Weather Service, National Centers for Environmental Prediction (5200 Auth Road, Camp Springs, Maryland, 20746 USA). Two NCEP reanalysis data sets were used in this study. The first was NCEP/NCAR, with 6-hourly data available from 1958 (see the URL provided below for further information). The second was the NCEP/DOE set, with 6-hourly data available from 1979 (see the URL provided below for further information). In this project the following model/analysis was applied: Application of The University of Melbourne cyclone tracking scheme (Simmonds et al., 2003, Monthly Weather Review, 131, 272-288) and a broad range of statistical tests. Brief details are provided in the Summary. See the link for the pdf document for more detailed information. These complex statistical analyses were run over the entire length of the project (2002/2003 - 2004/2005). They were run on the Sun Workstation cluster in the School of Earth Sciences, The University of Melbourne.

Current meter S4_211b is one of four current meters deployed off the coast of Casey Station, Australian Antarctic Territory. S4_211a was located in Shannon Bay at 66 degrees 16.727 minutes South, 110 degrees 31.434 minutes West. Further deployment details can be found in the 'Mooring Details' section of the data, as well as a 'Location Map'. The data includes: current speed components, current speed and current direction, a progressive vector diagram of displacement, and water temperature. The data were recorded by the Australian Antarctic Division, and processed by Oceanographic Field Services Pty Ltd. Data was recorded between 3:30am 18 November 1997 (GMT) and 7:30am 29 December 1998 (GMT). The fields in this dataset include: Date Time Speed (centimetres per second) Direction (degrees) Temperature (degrees)

Current meter data from the SAZ project - Sub-Antarctic zone mooring study of interannual variability in particulate carbon export. These data have been collected on cruises from 1997 to 2009. Each folder in the download file contains the data as well as a readme providing further information about data capture and quality for that year. See the parent record for further information.

AM01 borehole drilled January 2002 at a height of 65 metres above sea level. Current meter data dips collected during routine CTD operations over a period of 4 days upon completion of borehole. Consult Readme file for detail of data files and formats.