Turbidity is a measure of water clarity that quantifies the amount of small particles suspended in the water, and is a fundamental
environmental parameter influencing coastal marine ecosystems. Turbidity reduces the light needed for photosynthesis by corals
and seagrasses, and suspended particles also transport nutrients, pollutants and diseases. Previous research based on 3 years
of turbidity data collected from 15 inshore reefs by the Reef Rescue Marine Monitoring Program has shown that it can take
several months for water clarity to improve after river floods. This project will analyse a 12-year data set to demonstrate
the explicit link between variations in discharge (sediments and nutrients) from the major rivers in each Natural Resource
Management (NRM) region adjacent to the Great Barrier Reef (GBR) and seasonal and annual variations in water clarity in
the inshore GBR.
This project will:
1. Determine quantitative relationships between river discharges and seasonal and annual variation in inshore water clarity
on the GBR adjacent to each NRM region. This is achieved by processing MODIS/Aqua remote sensing (since July 2002) to calculate
euphotic depth (water clarity) for the whole GBR and analysing this against predicted and observed tides, observed waves,
wind, rain, river flow data (BOM and DERM daily data) and tidal forcing (Slim model).
2. Strengthen scientific basis for Reef Rescue and Reef Plan and the refinement of water quality targets.
3. Provide data to assist validation and calibration of the Receiving Waters Model and a WQ Risk Analysis.
This project is now complete.