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The international and interdisciplinary sea-ice drift expedition “The Multidisciplinary drifting Observatory for the Study of Arctic Climate” (MOSAiC) was conducted from October 2019 to September 2020. The aim of MOSAiC was to study the interconnected physical, chemical, and biological characteristics and processes from the atmosphere to the deep sea of the central Arctic system. The ecosystem team addressed current knowledge gaps and explored unknown biological properties over a complete seasonal cycle focusing on three major research areas: biodiversity, biogeochemical cycles, and linkages to the environment. In addition to the measurements of core properties along a complete seasonal cycle, dedicated projects covered specific processes and habitats, or organisms on higher taxonomic or temporal resolution in specific time windows. A wide range of sampling instruments and approaches, including sea-ice coring, lead sampling with pumps, rosette-based water sampling, plankton nets, remotely operated vehicles, and acoustic buoys, was applied to address the science objectives. Further, a broad range of process-related measurements to address, for example, productivity patterns, seasonal migrations, and diversity shifts, were made both in situ and onboard RV Polarstern. This article provides a detailed overview of the sampling approaches used to address the three main science objectives. It highlights the core sampling program and provides examples of habitat- or process-specific sampling. The initial results presented include high biological activities in wintertime and the discovery of biological hotspots in underexplored habitats. The unique interconnectivity of the coordinated sampling efforts also revealed insights into cross-disciplinary interactions like the impact of biota on Arctic cloud formation. This overview further presents both lessons learned from conducting such a demanding field campaign and an outlook on spin-off projects to be conducted over the next

Weather and climate models are challenged by uncertainties and biases in simulating Southern Ocean (SO) radiative fluxes that trace to a poor understanding of cloud, aerosol, precipitation, and radiative processes, and their interactions. Projects between 2016 and 2018 used in situ probes, radar, lidar, and other instruments to make comprehensive measurements of thermodynamics, surface radiation, cloud, precipitation, aerosol, cloud condensation nuclei (CCN), and ice nucleating particles over the SO cold waters, and in ubiquitous liquid and mixed-phase clouds common to this pristine environment. Data including soundings were collected from the NSF-NCAR G-V aircraft flying north-south gradients south of Tasmania, at Macquarie Island, and on the R/V Investigator and RSV Aurora Australis. Synergistically these data characterize boundary layer and free troposphere environmental properties, and represent the most comprehensive data of this type available south of the oceanic polar front, in the cold sector of SO cyclones, and across seasons. Results show largely pristine environments with numerous small and few large aerosols above cloud, suggesting new particle formation and limited long-range transport from continents, high variability in CCN and cloud droplet concentrations, and ubiquitous supercooled water in thin, multilayered clouds, often with small-scale generating cells near cloud top. These observations demonstrate how cloud properties depend on aerosols while highlighting the importance of dynamics and turbulence that likely drive heterogeneity of cloud phase. Satellite retrievals confirmed low clouds were responsible for radiation biases. The combination of models and observations is examining how aerosols and meteorology couple to control SO water and energy budgets.

The concept of Entrustable Professional Activities, recently pioneered in medical education, has emerged to support the implementation of competency‐based education. Although competency‐based frameworks are widely used in healthcare professional education to develop outcomes‐based curricula, assessment of student competency in professional placement settings remains challenging. The novel concept of Entrustable Professional Activities together with established methods of competency assessment, namely e‐portfolios and self‐assessment, was implemented in the “[La Trobe University Dietetic program in 2015–2016. This study aimed to appraise the e‐portfolio and evaluate the use of Entrustable Professional Activities to assess competence. A mixed‐methods evaluation, using qualitative and quantitative surveys with follow‐up structured consultations, was conducted with final year dietetics students and their supervisors. Dietetics students were comfortable with Entrustable Professional Activities and competency‐based assessment, whereas supervisors preferred Entrustable Professional Activity based assessment. All stakeholders valued student self‐assessment and the ongoing use of structured e‐portfolios to develop and document competency. The use of structured e‐portfolios, student self‐assessment, and the emerging concept of Entrustable Professional Activities are useful tools to support dietetics student education in professional placement settings.

Extra virgin olive oil (EVOO) is suggested to be cardioprotective, partly due to its high phenolic content. We investigated the effect of extra virgin high polyphenol olive oil (HPOO) versus low polyphenol olive oil (LPOO) on blood pressure (BP) and arterial stiffness in healthy Australian adults. In a double-blind, randomized, controlled cross-over trial, 50 participants (age 38.5 ± 13.9 years, 66% female) were randomized to consume 60 mL/day of either HPOO (360 mg/kg polyphenols) or LPOO (86 mg/kg polyphenols) for three weeks. Following a two-week washout period, participants crossed over to consume the alternate oil. Anthropometric data, peripheral BP, central BP and arterial stiffness were measured at baseline and follow up. No significant differences were observed in the changes from baseline to follow up between the two treatments. However, a significant decrease in peripheral and central systolic BP (SBP) by 2.5 mmHg (95% CI: −4.7 to −0.3) and 2.7 mmHg (95% CI: −4.7 to −0.6), respectively, was observed after HPOO consumption. Neither olive oil changed diastolic BP (DBP) or measures of arterial stiffness. The reductions in SBP after HPOO consumption provide evidence for a potentially widely accessible dietary intervention to prevent cardiovascular disease in a multiethnic population. Longer intervention studies and/or higher doses of EVOO polyphenols are warranted to elucidate the potential effect on DBP and arterial stiffness.

The 2015/16 ENSO event increased the temperature of waters surrounding northeast Australia to above 30 °C, with large patches of water reaching 32 °C, for over two months, which led to severe bleaching of corals of the Northern Great Barrier Reef (NGBR). This study provides evidence gained from remote-sensing data, oceanographic data and oceanographic modeling, that three factors caused this excessive heating, namely: 1) the shutdown of the North Queensland Coastal Current, which would otherwise have flushed and cooled the Northern Coral Sea and the NGBR through tidal mixing 2) the advection of warm (>30 °C) water from the Gulf of Carpentaria eastward through Torres Strait and then southward over the NGBR continental shelf, and 3) presumably local solar heating. The eastward flux of this warm water through Torres Strait was driven by a mean sea level difference on either side of the strait that in turn was controlled by the wind, which also generated the southward advection of this warm water onto the NGBR shelf. On the NGBR shelf, the residence time of this warm water was longer inshore than offshore, and this may explain the observed cross-shelf gradient of coral bleaching intensity. The fate of the Great Barrier Reef is thus controlled by the oceanography of surrounding seas., Author Accepted Manuscript, Mathematical Physics

Dispersal patterns shape species’ distribution, abundance and persistence, their potential for genetic drift and adaptation, and ultimately determine rates of recovery following disturbances. Because the larval mortality and competency dynamics of most marine organism is altered under warmer conditions, it is fundamental to understand how climate change will alter current connectivity patterns. Here we used an experimentally calibrated high-resolution unstructured-mesh, depthintegrated hydrodynamic model (SLIM) to project current and climate change-mediated dispersal and connectivity patterns of corals in the Great Barrier Reef (GBR). We show that as oceans warm, coral connectivity will decrease. Specifically, the average dispersal distance from origin to destination reef and the number of incoming connections to each reef decrease. Interestingly, the proportion of larvae that find a suitable place to settle increases because more larvae will settle in their natal reef. We also show that broadcast spawning species with greater egg sizes, such as Acropora spp., will experience greater changes in dispersal patterns than species with smaller eggs. We identified the reefs which contribute the most to the larval supply in the GBR and the reefs which recovery rates will be more affected by the change in connectivity patterns. Improved predictions of coral connectivity are essential to design networks of protected areas that contribute more effectively to the long-term sustainability and resilience of tropical reef ecosystems.