A5048530627- Marine and coastal ecosystems
- Marine Biology and Ecology Research
- Oceanographic and Atmospheric Processes
- Geology and Paleoclimatology Research
- Ocean Acidification Effects and Responses
- Isotope Analysis in Ecology
- Microbial Community Ecology and Physiology
- Methane Hydrates and Related Phenomena
- Geological and Geochemical Analysis
- Atmospheric and Environmental Gas Dynamics
- Marine Bivalve and Aquaculture Studies
- earthquake and tectonic studies
- Marine and fisheries research
- Paleontology and Stratigraphy of Fossils
- Geochemistry and Elemental Analysis
- High-pressure geophysics and materials
- Marine and environmental studies
- Arctic and Antarctic ice dynamics
- Geomagnetism and Paleomagnetism Studies
- Coral and Marine Ecosystems Studies
- Groundwater and Isotope Geochemistry
- Diatoms and Algae Research
- Polar Research and Ecology
- Global Energy and Sustainability Research
- Climate variability and models
University of Tasmania
2015-2024
Commonwealth Scientific and Industrial Research Organisation
2015-2024
CSIRO Oceans and Atmosphere
2015-2024
Australian Antarctic Division
1999-2024
Antarctic Climate and Ecosystems Cooperative Research Centre
2013-2022
Health Sciences and Nutrition
2019-2022
National Institute of Water and Atmospheric Research
2007-2021
Aix-Marseille Université
2021
Université de Toulon
2021
Centenary Institute
2007-2018
The oceanic biological pump drives sequestration of carbon dioxide in the deep sea via sinking particles. Rapid consumption and remineralization âtwilight zoneâ (depths between euphotic zone 1000 meters) reduce efficiency sequestration. By using neutrally buoyant sediment traps to sample this chronically understudied realm, we measured a transfer particulate organic 150 500 meters 20 50% at two contrasting sites. This large variability is poorly represented biogeochemical models. If...
This review provides an assessment of sediment trap accuracy issues by gathering data to address hydrodynamics, the problem zooplankton "swimmers," and solubilization material after collection.For each topic, is identified, its magnitude causes reviewed using selected examples, update on methods correct for potential bias or minimize new technologies presented.To hydrodynamic biases due flow over mouth, use neutrally buoyant traps encouraged.The influence swimmers best minimized that limit...
The Argo Program has been implemented and sustained for almost two decades, as a global array of about 4000 profiling floats. provides continuous observations ocean temperature salinity versus pressure, from the sea surface to 2000 dbar. successful installation its innovative data management system arose opportunistically combination great scientific need technological innovation. Through system, fundamental physical with broad societally-valuable applications, built on cost-efficient robust...
The Biogeochemical-Argo program (BGC-Argo) is a new profiling-float-based, ocean wide, and distributed monitoring which tightly linked to, has benefited significantly from, the Argo program. community recommended for BGC-Argo addition of six measurements in to pressure, temperature salinity measured by Argo, include oxygen, pH, nitrate, downwelling light, chlorophyll fluorescence optical backscattering coefficient. purpose this enable biogeochemistry health, particular, monitor major...
Effective data management plays a key role in oceanographic research as cruise-based data, collected from different laboratories and expeditions, are commonly compiled to investigate regional global processes. Here we describe new updated best practice standards for discrete chemical observations, specifically those dealing with column header abbreviations, quality control flags, missing value indicators, standardized calculation of certain properties. These have been developed the goals...
Climate change is projected to significantly alter the delivery (stratification, boundary currents, aridification of landmasses, glacial melt) iron Southern Ocean. We report most comprehensive suite biogeochemical budgets date for three contrasting sites in subantarctic and polar frontal waters south Australia. Distinct regional environments were responsible differences mode strength supply mechanisms, with higher stocks fluxes observed surface northern waters, where atmospheric greater....
Optical particle measurements are emerging as an important technique for understanding the ocean carbon cycle, including contributions to estimates of their downward flux, which sequesters CO2 in deep sea. instruments can be used from ships or installed on autonomous platforms, delivering much greater spatial and temporal coverage particles mesopelagic zone than traditional techniques, such sediment traps. Technologies image have advanced greatly over last two decades, but quantitative...
Abstract. The first KErguelen Ocean and Plateau compared Study (KEOPS1), conducted in the naturally iron-fertilised Kerguelen bloom, demonstrated that fecal material was main pathway for exporting carbon to deep ocean during summer (January–February 2005), suggesting a limited role of direct export via phytodetrital aggregates. KEOPS2 project reinvestigated this issue spring bloom initiation (October–November 2011), when zooplankton communities may exert grazing pressure, further explored...
Abstract. Ship-based time series, some now approaching over 3 decades long, are critical climate records that have dramatically improved our ability to characterize natural and anthropogenic drivers of ocean carbon dioxide (CO2) uptake biogeochemical processes. Advancements in autonomous marine sensors technologies the last 2 led expansion observations at fixed series sites, thereby improving capability characterizing sub-seasonal variability ocean. Here, we present a data product 40...
Abstract. Field campaigns are instrumental in providing ground truth for understanding and modelling global ocean biogeochemical budgets. A survey however can only inspect a fraction of the oceans, typically region 100s km wide temporal window order (at most) several weeks. This spatiotemporal domain is also one which mesoscale activity induces through horizontal stirring strong variability tracers, with ephemeral, local contrasts easily mask regional seasonal gradients. Therefore, whenever...
Phytoplankton assimilation and microbial oxidation of ammonium are two critical conversion pathways in the marine nitrogen cycle. The underlying regulatory mechanisms these competing processes remain unclear. Here we show that ambient nitrate acts as a key variable to bifurcate flow through or oxidation, depth nitracline represents robust spatial boundary between assimilators oxidizers stratified ocean. Profiles utilization phytoplankton assemblages nitrate-depleted regimes have higher...
Abstract Mesoscale eddies are ubiquitous in the iron-limited Southern Ocean, controlling ocean-atmosphere exchange processes, however their influence on phytoplankton productivity remains unknown. Here we probed biogeochemical cycling of iron (Fe) a cold-core eddy. In-eddy surface dissolved Fe (dFe) concentrations and were exceedingly low relative to external waters. Fe-to-carbon uptake ratios elevated 2–6 fold, indicating upregulated intracellular acquisition resulting dFe residence time ~1...
The influence of irradiance and iron (Fe) supply on phytoplankton processes was investigated, north (47°S, 142°E) south (54°S, the Subantarctic Front in austral autumn (March 1998). At both sites, resident cells exhibited nutrient stress ( F υ / m <0.3). Shipboard perturbation experiments examined two light (mean situ elevated) Fe (nominally 0.5 3 nM) treatments under silicic acid‐replete conditions. Mean levels (derived from incident irradiances, mixed layer depths (MLDs), wind stress, a...
The circumpolar Subantarctic Zone (SAZ) is a globally significant region of water mass formation and carbon dioxide uptake from the atmosphere. Here we synthesize results nine voyages over 8 years to describe seasonal variation in mixed layer properties SAZ south Australia for comparison with biogeochemical process studies carried out late summer (March 1998) as part Project. Winter mixing extends depths >400 m, resulting Mode Water. In shoals 75–100 which are still sufficiently deep that...
Sediment trap moorings were deployed from September 21, 1997 through February 1998 at three locations south of Australia along 140°E: ∼47°S in the central Subantarctic Zone (SAZ) with traps 1060, 2050, and 3850 m depth, ∼51°S Front one 3080 m, ∼54°S Polar Frontal (PFZ) 830 1580 m. Particle fluxes high all sites (18–32 g −2 yr −1 total mass 0.5–1.4 organic carbon −1000 assuming minimal flux outside sampled summer period). These values are similar to other Southern Ocean results median...