Project Overview

Broad description / context:

Phytoplankton are the microscopic photosynthesizing algae inhabiting the surface sunlit layers of the oceans. They form the basis of all oceans’ life, produce more oxygen than all terrestrial plants and sustain global fisheries. They are quantifiable using satellite ocean colour radiometry (OCR) because they modify the spectral composition of the light outcoming from the ocean and reaching the satellite sensors. Better quantifying their trends is crucial to understand past changes in this fundamental basis link of the entire ocean ecosystem, then contributing to predict their future response to a globally changing ocean environment. To achieve this goal, one requires satellite observations that are consistent over long periods of time, which is achieved through a process called "System Vicarious Calibration" (SVC). Curtin's Remote Sensing and Satellite Research Group are in charge of an infrastructure delivering data used for this SVC process, called MarONet (see below).

Some details on what "Satellite Ocean Colour Radiometry (OCR) System Vicarious Calibration (SVC)" is:

OCR-SVC is a relative radiometric calibration of satellite ocean colour sensors that minimizes uncertainties in the water-leaving radiance, Lw, derived from the total radiance measured at the top of the atmosphere, Lt. This is achieved through applying gains to pre-launch absolute radiometric calibration coefficients of the satellite sensor. The gains are determined by the ratio of simulated to measured spectral Lt values where the former are computed through radiative transfer using highly accurate in situ Lw measurements and atmospheric models. OCR-SVC is indispensable to meet the highly stringent requirements of OCR data quality, and accordingly has been applied to all NASA satellite OCR missions following agreed general principles.

See this link if you want more details on OCR-SVC: https://ioccg.org/group/vical/

Some details on the MarONet project in general:

The Marine Optical Network, MarONet, has been specifically developed to support the newly launched NASA “Plankton, Aerosol, Cloud, ocean Ecosystem” mission (PACE), the first global hyperspectral OCR mission. MarONet consists of two identical buoys deployed off Hawaii and Perth, which host a new generation of field deployable spectrometers. They are the evolution of the "MOBY" system that NASA used for many years (since 1997) and was deployed in Hawaii. The rationale for 2 sites as part of MarONet is to collect more data in any given time frame, to include different atmospheric and oceanic conditions in the SVC process, and to combine geometries of observation by having sites in both hemispheres. The Perth site was chosen for its often extremely clear atmosphere, moderate variability of ocean optical properties. The buoy site will be complemented by a ground station on Rottnest Island measuring sky radiances for determination of aerosol properties.

See this link if you want more details about PACE: https://pace.oceansciences.org

Aims

This project aims to improve the reliability of multi-decadal climate-change-driven trends of ocean phytoplankton that are derived from satellite ocean colour radiometry observations. This will be achieved by improving the so-called System Vicarious Calibration techniques currently in use.

Objectives

The general goal will be achieved by combining:

i) data from a new-generation sea-deployable optical system providing reference measurements of the ocean reflectance; this is MarONet.

ii) a new ground-based site for atmospheric aerosol measurements,

iii) the latest developments in radiative transfer simulations of satellite observations and numerical inversion of radiometry measurements to derive aerosols properties and,

iv) a multi-sensor ocean colour processing workflow that we previously developed.

Significance 

The proposed project will create new knowledge and have multiple benefits.

i) New SVC techniques will be developed for hyperspectral sensors like PACE, which are the future of satellite OCR.

ii) The project will help improving data quality of existing or future satellite OCR missions, hence with impact on a huge community of data users worldwide. They include, e.g., state environment departments, fisheries and aquaculture industries, non-governmental organisations, the IPCC (the ecosystems response to further climate change is still a major uncertainty in their assessments), and the science community of course.

iv) More robust information on the response of phytoplankton to their changing environment are also expected. This will allow ultimately better assessing climate-change-related evolution of our oceans’ ecosystems.

• Future Students

• Faculty of Science & Engineering
  • Science courses
  • Engineering courses

• Higher Degree by Research

• Australian Citizen
• Australian Permanent Resident
• New Zealand Citizen
• Permanent Humanitarian Visa
• International Student

• Merit Based

The annual scholarship package, covering both stipend and tuition fees, amounts to approximately $70,000 per year.

In 2024, the RTP stipend scholarship offers $35,000 per annum for a duration of up to three years. Exceptional progress and adherence to timelines may qualify students for a six-month completion scholarship.

Selection for these scholarships involves a competitive process, with shortlisted applicants notified of outcomes by November 2024.

1

All applicable HDR courses.

We are looking for a self-motivated PhD candidate with excellent organisation and problem-solving skills and a strong physics background, ideally including some knowledge/experience in radiative transfer in geophysical media (ocean / atmosphere). Graduates from environment physics / sciences might also be considered if having the necessary foundation skills. Ideally, applicants should have some background in satellite ocean colour remote sensing.  Excellent programming skills (e.g., Python, R and also low-level languages like Fortran) will be needed as well. The applicant would also be interested in current questions about how ocean environments and ecosystems are changing in response to climate change.

 

Please send your CV, academic transcripts and brief rationale why you want to join this research project via the HDR expression of interest form to the project lead researcher, listed below. 

You must be enrolled in a Higher Degree by Research Course at Curtin University by March 2025.

Project Lead: Professor David Antoine