Benthic Reflectance Maps for Coral Sea Atolls from Sentinel-2 and Bathymetry

A 2026 code repository and dataset from the Australian Ocean Data Network details a method for estimating seafloor reflectance up to 50-60 meters deep using Sentinel-2 satellite imagery and bathymetry data. The dataset includes case studies for three reef complexes in the Coral Sea and part of the Great Barrier Reef, assessing the method's sensitivity to input data quality. It processes the first four spectral bands of Sentinel-2 imagery to evaluate their effectiveness for deep-water benthic mapping.

Use Cases

• Mapping sand versus vegetation on the seafloor based on estimated benthic reflectance.
• Assessing the depth penetration of different Sentinel-2 spectral bands for benthic feature detection.
• Testing the sensitivity of reflectance models to degraded bathymetry resolution or missing sun glint correction.
• Providing a visual reference to improve confidence in manual mapping of oceanic vegetation on coral atolls.

Strengths

• Method enables benthic reflectance mapping to depths of 50-60 meters, exceeding typical 10-20 meter limits of multispectral approaches.
• Includes case studies for multiple named reef complexes (Flinders, Holmes, Lihou, Davies, Grub, Chicken, Bowl Reefs).
• Assesses method sensitivity by testing with bathymetry data at 1/10th the resolution of the satellite imagery.

Limitations

• Method only works where water is clear, matching bathymetry data exists, and there are enough flat light/dark areas for model fitting.
• Row count and specific data volume are unknown, which may limit suitability assessment.
• Column-level documentation is absent; field semantics must be inferred after download.

Provenance

Source

Australian Ocean Data Network

Collection Method

Benthic reflectance estimated from satellite imagery (Sentinel-2) and bathymetry digital elevation models.

Freshness

Last updated 2026-07-16 02:04:45.435346; freshness should be verified.

Geography

Coral Sea (Flinders, Holmes, Lihou Reefs) and part of the Great Barrier Reef north-east of Townsville.