Subantarctic Zone (SAZ) Project and Sediment Trap Moorings

• Other Authors: AADC (originator), AU/AADC > Australian Antarctic Data Centre, Australia (resourceProvider)
• Format: Dataset
• Language: unknown
• Published: Australian Ocean Data Network
• Subjects: geoscientificInformation; oceans; SEDIMENTATION; EARTH SCIENCE; MARINE SEDIMENTS; DATE; DEPTH BELOW SEA LEVEL; FLUX; GEOSCIENCES; LATITUDE; LONGITUDE; OCEAN CHEMISTRY; OCEANOGRAPHY; POSITION; TIME; MOORINGS; R/V AA > R/V Aurora Australis; SHIPS; AMD/AU; CEOS; AMD; ACE/CRC; OCEAN > SOUTHERN OCEAN; GEOGRAPHIC REGION > POLAR; Southern Ocean; aurora australis
• Online Access: https://researchdata.ands.org.au/subantarctic-zone-saz-trap-moorings/685361; https://data.aad.gov.au/metadata/records/SAZOTS; http://data.aad.gov.au/aadc/portal/download_file.cfm?file_id=1927; https://secure3.aad.gov.au/proms/public/projects/report_project_public.cfm?project_no=1156; http://data.aad.gov.au/aadc/metadata/citation.cfm?entry_id=SAZOTS

The values provided in temporal and spatial coverage are approximate only. Taken from the 2008-2009 Progress Report: Variations to work plan or objectives: 1. to accelerate our development program, we deployed two Pulse test moorings instead of one. Both designs were successful in terms of surviving the high seas, and we are currently evaluating mooring accelerometer data to choose the best design in terms of minimising stresses on instruments. 2. we moved the deep sediment trap mooring from its usual site (near 47 S, 140 E) to a site closer to Tasmania (near 45 S, 146 E). We did this for logistical reasons - to allow for deployment from the Marine Trials voyage, but we also expect scientific gains because this site is in the region where waters from the East Australian Current extension pass westward south of Tasmania, and thus we will be able to compare sinking particle fluxes from these waters with those from the more southerly, cooler Subantarctic waters studied previously. This is particularly advantageous because these warmer westerly flows are expected to increase in future as a result of climate warming, and thus this work gets us an early look at possible ecosystem and carbon cycling responses. Field work: Three moorings were deployed from the Aurora Australis marine science trials voyage, 3-12 Oct 2008. Mooring 'SAZ 45-11' was deployed at 44.8 deg S, 145 deg E and is due to be recovered in September 2009. It was instrumented with 3 Mclane time series sediment traps, 2 Indented Rotating Sphere sediment traps in settling velocity mode, and 1 current meter. The two PULSE engineering test moorings were deployed at PULSE5-Light - 44.2 deg S, 146.4 deg E. PULSE5-Heavy - 44.2 deg S, 146.5 deg E. and recovered in April 2009 with Marine National Facility support. Laboratory activity/analysis: A method to analyse the sediment trap samples for silicon and aluminium with micro x-ray fluorescence (uXRF) has been evaluated, and samples are currently being analysed. This will complete the dataset of core parameters ie fluxes for total mass, inorganic carbon, organic carbon, and biogenic silica. Please also see the child records of this project for access to data. Attached to this record are the originally supplied datasets for 1997-1998, and also summary files and mooring diagrams supplied in 2012. Taken from the 2008-2009 Progress Report: Progress against objectives: The key to advancing the objective of understanding ocean processes controlling uptake of atmospheric CO2 is the ability to deploy moored autonomous samplers and sensors in Southern Ocean surface waters capable of quantifying seasonal cycles in biological and biogeochemical processes. Our effort in the last 12 months has focused on development of a robust mooring platform to carry these devices. We deployed two different engineering test designs, known as Pulse 5 Heavy and Pulse 5 Light. Both designs survived 6 months in the sea, including wave heights up to 12 meters, while transmitting mooring tensions, mooring accelerations, and GPS positions live to the internet (www.imos.org.au). Following this success we are preparing to deploy the next version of Pulse with scientific instruments to measure temperature, salinity, oxygen, and phytoplankton fluorescence. In addition we deployed a deep ocean mooring with time-series sediment traps to quantify sinking particle fluxes, and in-situ settling columns to determine particle sinking rates. Taken from the 2009/2010 Progress Report: Progress against objectives: Two voyages were awarded by the Australian Marine National Facility to use RV Southern Surveyor to service these Southern Ocean Time Series (SOTS) moorings in the 2009/10 season, and for this reason the shiptime awarded to this project by AAS was not needed and was relinquished. This arrangement will continue in 2010/11 for which the MNF has again awarded two voyages in September 2010 and April 2011. The fieldwork in 2009/10 was very successful: i) the SAZ deep sediment trap mooring was recovered in September 2009 and redeployed for recovery in September 2010. ii) the PULSE biogeochemistry mooring was deployed in September 2009 and functioned beautifully prior to recovery in March 2010 for servicing. It will be redeployed in September 2010. iii) the SOFS Southern Ocean Flux Station mooring was completed and deployed in March 2010 for recovery in April 2011, and redeployment in September 2011.