Dynamics of a marine heatwave: what happens below the surface?

Extreme temperatures in the ocean are getting more frequent and intense, impacting marine ecosystems and industries. However the subsurface signature of these marine heatwaves is still largely unknown, in particular in shallow coastal areas where most of the ecological damages occur.

In addition to sustained observations, the Australian Integrated Marine Observing System (IMOS) now aims at sampling the coastal ocean during marine heatwaves with real-time deployments of ocean gliders. Gliders are automated underwater vehicles which measure the water properties between the ocean floor and the surface for a few weeks. Two of such deployments were successfully finalised, sampling the eastern shelf of Tasmania during the latest marine heatwave event in the Tasman Sea in summer / spring 2019.

The project aims at understanding the extent and characteristics of marine heatwaves using glider measurements and complementary satellite and moored observations. Key questions include the temporal evolution, from the onset to the decline of the extreme event, and the influence of the local oceanography such as currents and wind-driven processes on the persistence and variability of these anomalous temperatures. The student will use programming language to analyse this unique dataset and compute the heat budget equations.

Basic knowledge of oceanography and experience in Matlab or Python are required. The project will be based at UNSW Sydney, co-supervised by Amandine Schaeffer (UNSW), Jessica Benthuysen (AIMS) and Neil Holbrook (UTAS).

Contact: a.schaeffer@unsw.edu.au

Understanding how precipitation extremes scale in future climates

While global climate models (GCMs) remain our best tool for investigating the Earth’s system response to anthropogenic forcings, their spatial resolution (generally hundreds of km) is much coarser than the scales of the key processes leading to precipitation extremes (e.g. intense convective rainfall events). Therefore, parametrizations are necessary and the simulation of precipitation is not explicitly resolved in models. Spatial resolution is finer in regional climate models (RCMs) (generally tens of km), which is expected to improve the simulation of precipitation extremes that are very sensitive to spatial contrasts and topography. However, even at the scales of regional models parametrizations are still required.

Global and regional models have advantages and disadvantages for studying precipitation extremes, but how their output scales with respect to the other is rarely compared. In particular, it is unclear how the future changes in precipitation extremes from large ensembles of regional climate models compare to those from global models. This project will assess how precipitation projections for Australia from global and regional models scale using the latest start-of-the-art GCMs and RCMs.

Requirements: Some prior programming and data visualisation experience (e.g. Python, NCL, MATLAB, R, etc.).

This project is supervised by A/Prof Lisa Alexander and Dr Margot Bador (UNSW Sydney). Please contact l.alexander@unsw.edu.au for more information.

 

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Upcoming workshop on the future of Earth-observing satellites

Researchers and partners from industry, government, and academia are invited to a free workshop on May 24th 2019 to discuss the future of satellite-based remote sensing of Earth’s water resources and ocean dynamics. The workshop will be held at the Sydney Bureau of Meteorology and streamed live to the web.

In the coming decade, new satellite missions will map Earth’s surface water and sea level (ocean topography) at a resolution that has not been possible before. These observations will provide critical information that is needed to assess water resources on land, track regional sea level changes, monitor coastal processes, and observe small-scale ocean currents and eddies. The first of these satellites, the NASA/CNES Surface Water Ocean Topography (SWOT) mission, is scheduled for launch in late 2021.

The workshop on future high-resolution satellite altimetry is organized by the Australian Bureau of Meteorology and the Australian Surface Water Ocean Topography (AUSWOT) working group, a consortium of researchers and stakeholders from industry, government, and academia that aims to develop Australia’s capability in the field of surface water and ocean topography and address key issues relevant to the Asia-Pacific region.

All researchers and partners are invited to participate in this free workshop. Click here to find out more information and to register.

PhD Project: Wake interference by swimming crocodiles

Crocodiles, including the saltwater crocodile (Crocodylus porosus) have the remarkable ability to swim underwater at high speed while barely making a ripple at the surface. It has been hypothesized that crocodiles are able to do this because the bony ridges on the crocodile’s back (called scutes or osteoderms) produce destructively interfering wake patterns at the water surface, like noise-cancelling headphones. Understanding and replicating this phenomena could have important implications for submarine and ship hull design.

In this project, we will evaluate this hypothesis using a combination of theory, numerical modelling, and laboratory experiments using 3D-printed crocodile models in a wave flume. Experience with Python programming is essential. This project will be co-supervised by Dr Geoff Vasil (U. Sydney), Dr Chris Lustri (Macquarie) and Dr Shane Keating (UNSW).

Click here for key dates and to submit your application online.

University-Industry partnership to focus on Dry Eye Syndrome

UNSW Sydney is collaborating with the non-profit Brian Holden Vision Institute and medical device company TeleMedC in a new $445,000 research project to develop a state-of-the-art computational model of tear film dynamics of a blinking eye.

Each time you blink, your eyes replenish the tear film, a thin fluid interface between the surface of the eye and the environment. Although it is less than a tenth the thickness of a human hair, the tear film plays an important role in cleaning and protecting the delicate ocular surface while maintaining clear vision. Chronic breakdown of the tear film is associated with Dry Eye Syndrome, a debilitating disease that affects millions of Australians and up to half those aged over 50.

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Anatomy of the tear film. Credit: James J. Feng, UBC.

 

A critical knowledge gap is the clinical and environmental factors affecting tear film break up in both healthy subjects and dry-eye patients. The project will address this knowledge gap by developing a state-of-the-art computational model of tear film, validated against in vitro and in vivo data, suitable for clinical studies by researchers in both academia and industry.

The new research partnership involves Dr Shane Keating at UNSW’s School of Mathematics & Statistics and Dr Nicole Carnt at UNSW’s School of Optometry & Vision Science, and Prof Arthur Ho at the Brian Holden Vision Institute. The project will be carried out in collaboration with TeleMedC, LCC, a pioneering medical device company that is developing the next generation of ophthalmic diagnostic imaging systems for face-to-face and virtual medical consultations, screening, monitoring and health prevention purposes for remote and urban communities.

UNSW Sydney has awarded a prestigious Scientia PhD scholarship to PhD student Yu Wang to work with Shane, Nicole, and Arthur on developing the computational model of the tear film. The Scientia scholarship scheme aims to harness cutting-edge research to solve complex problems and improve the lives of people in local and global communities. Scientia scholars receive a $200,000 scholarship package in the form of a stipend, travel, and development support over four years. International scholars also receive a tuition fee scholarship worth $200,000. In addition, UNSW Sydney and TeleMedC, LLC have provided $45,000 in support for the project through the Industry Network Seed Fund program.