Degree type
PhD
Closing date
1 October 2024
Campus
Hobart
Citizenship requirement
Domestic / International
About the research project
Introduction
The global climate crisis poses a serious threat to the well-being of humanity and the natural environment. To limit the global warming to well below 2°C, as agreed in the Paris Agreement, it is not enough to reduce greenhouse gas emissions, but also to actively remove carbon dioxide (CO2) from the atmosphere. One of the potential methods for CO2 removal is Ocean Alkalinity Enhancement (OAE), which involves increasing the alkalinity of seawater to enhance its capacity to absorb and store CO2. OAE has several advantages over other CO2 removal techniques, such as low energy requirements and a theoretical potential. However, OAE also faces many challenges and uncertainties, such as the feasibility, scalability, cost, and environmental impacts of different alkalinity sources and delivery methods. Therefore, field experimentation is the necessary step that needs to be undertaken to explore OAE and its potential implications for the marine carbon cycle and climate change mitigation under real-world conditions.
Chapter 1: Development and deployment of Raspberry Pi based sensors for marine carbonate chemistry observations
The first chapter of this project aims to build precise, yet cheap, Raspberry Pi based sensors for observations on marine carbonate chemistry. The goal is to establish an alkalinity budget for a semi-enclosed basin such as a lagoon. The alkalinity budget is the balance between the sources and sinks of alkalinity in a given water body, and it determines the buffering capacity and pH of the water. The alkalinity budget is also influenced by various biogeochemical processes, such as photosynthesis, respiration, calcification, and carbonate dissolution. By measuring the alkalinity and other parameters of the carbonate system, such as pH, dissolved inorganic carbon, and partial pressure of CO2, we can quantify the fluxes and transformations of carbon and alkalinity in the lagoon and assess how well we can constrain an alkalinity budget within a semi-enclosed basin.
The Raspberry Pi based sensors will be designed and calibrated using open-source hardware and software, and validated against standard methods and instruments. The sensors will be deployed in the lagoon at different depths and locations. The sensors will provide high-resolution and long-term data on the spatial and temporal variability of the carbonate chemistry in the lagoon, and enable the estimation of the alkalinity budget using mass balance.
Chapter 2: Identification and quantification of alkalinity influxes from rivers and groundwater discharge
The second chapter of this project aims to identify and quantify the influxes of alkalinity into the same lagoon via rivers and groundwater discharge. This will inform to what extent terrestrial freshwater fluxes into the coastal marine environment affect the alkalinity budget of the coastal ocean. Rivers and groundwater are important sources of alkalinity to the ocean, as they transport dissolved minerals and organic matter from weathering and erosion of rocks and soils. The amount and composition of alkalinity delivered by rivers and groundwater depend on various factors, such as the geology, hydrology, land use, and climate of the catchment area. The alkalinity influxes from rivers and groundwater can have significant impacts on the carbonate chemistry and biogeochemistry of the coastal ocean, such as increasing the pH, reducing the CO2 concentration, enhancing the calcification, and stimulating the primary production.
The alkalinity influxes from rivers and groundwater will be measured and characterized using a combination of hydrological, geochemical, and isotopic methods. The riverine alkalinity will be sampled and analyzed at different flow regimes and seasons. The alkalinity fluxes from rivers and groundwater will be compared and contrasted with the alkalinity fluxes from other sources and sinks in the lagoon, and their relative contributions and influences on the alkalinity budget and the carbonate chemistry will be evaluated.
Chapter 3: Constraining the alkalinity budget for a planned field experiment on Ocean Alkalinity Enhancement
The third chapter of this project will be to constrain the alkalinity budget for a planned field experiment on OAE, using the knowledge obtained in chapters one and two. The field experiment will involve adding a certain amount of alkalinity to a selected area of the lagoon, and monitoring the changes in the carbonate chemistry and the CO2 uptake before, during, and after the addition. The alkalinity budget will be used to estimate the optimal dose and duration of the alkalinity addition, and to evaluate the efficiency and effectiveness of the OAE technique in enhancing the CO2 removal and storage in the lagoon.
The field experiment will also assess the potential benefits and risks of OAE for the marine ecosystem and the local community. The benefits may include increasing the pH, reducing the ocean acidification, improving the coral reef health, and boosting the fishery productivity. The risks may include altering the nutrient cycling, affecting the plankton community, changing the food web structure, and causing unintended side effects. This shall be achieved in collaboration other members of the "Applied Biogeochemistry" research group.
Conclusion
This project will provide novel and valuable insights into the feasibility and implications of OAE as a CO2 removal technique. It will also contribute to the advancement of the scientific knowledge and the technological innovation in the fields of marine carbonate chemistry, coastal oceanography, and climate engineering. The expected outcomes of this project are:
*A set of low-cost and high-precision Raspberry Pi based sensors for marine carbonate chemistry observations, which can be replicated and applied in other coastal regions and environments.
*A comprehensive and accurate alkalinity budget for a semi-enclosed basin, which can serve as a baseline and a reference for future studies and interventions on the marine carbon cycle and ocean acidification.
*A successful and informative field experiment on OAE, which can demonstrate the potential and the challenges of this technique for climate change mitigation and marine ecosystem conservation.
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Funding
Applicants will be considered for a Research Training Program (RTP) scholarship or Tasmania Graduate Research Scholarship (TGRS) which, if successful, provides:
- a living allowance stipend of $32,192 per annum (2024 rate, indexed annually) for 3.5 years
- a relocation allowance of up to $2,000
- a tuition fees offset covering the cost of tuition fees for up to four years (domestic applicants only)
If successful, international applicants will receive a University of Tasmania Fees Offset for up to four years.
As part of the application process you may indicate if you do not wish to be considered for scholarship funding.
Other funding opportunities and fees
For further information regarding other scholarships on offer, and the various fees of undertaking a research degree, please visit Scholarships and fees.
Eligibility
Applicants should review the Higher Degree by Research minimum entry requirements.
Ensure your eligibility for the scholarship round by referring to our Key Dates.
Additional eligibility criteria specific to this project/scholarship:
- Applicants must be able to undertake the project on-campus
Selection Criteria
The project is competitively assessed and awarded. Selection is based on academic merit and suitability to the project as determined by the College.
Additional essential selection criteria specific to this project:
- Strong background in marine biogeochemistry
- Skills in sensor development, ideally based on raspberry Pi or Arduino
- Coding and programming skills for sensor development
- Willingness to conduct research in the field
- Problem-solving ambition and skills
- Strong interest in and motivation to work on potential tools to counteract climate change
Application process
- Select your project, and check that you meet the eligibility and selection criteria, including citizenship;
- Contact A/Prof Lennart Bach to discuss your suitability and the project's requirements; and
- In your application:
- Copy and paste the title of the project from this advertisement into your application. If you don’t correctly do this your application may be rejected.
- Submit a signed supervisory support form, a CV including contact details of 2 referees and your project research proposal.
- Apply prior to 1 October 2024.
Full details of the application process can be found under the 'How to apply' section at Research degrees.
Following the closing date applications will be assessed within the College. Applicants should expect to receive notification of the outcome by email by the advertised outcome date.
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