Satellite Analysis of Seven Northern Australian Estuaries

Northern Australian estuaries, including Darwin Harbour and the Keep, Daly, Roper, Macarthur, Flinders, and Gilbert River systems, are analyzed using the Digital Earth Australia Landsat archive. This report assesses a satellite remote sensing approach for mapping intertidal areas, mangrove extent, and habitat change over a three-decade time series. The work focuses on habitats critical for threatened and migratory shorebird species.

Use Cases

• Apply the Intertidal Extent Model from DEA to map the extent and morphology of estuarine intertidal environments.
• Use tide-tagged satellite imagery to isolate and remove tide-induced change from change-detection analyses of coastal habitats.
• Analyze geometric median composites of surface reflectance to produce cloud-free images depicting maximum observed tidal extent.
• Detect coastal habitat change, such as mangrove expansion or die-back, using the high-density Landsat time series across seven estuaries.

Strengths

• Analysis covers seven specific estuaries in northern Australia selected for their ecological importance.
• Utilizes a three-decade long Landsat time series from the Digital Earth Australia archive.
• Employs specific analytical methods like tide-tagging and the Intertidal Extent Model to address regional challenges like cloud interference.

Limitations

• Primary data format is a PDF report, limiting direct machine-readability and programmatic analysis of underlying geospatial data.
• Scope is a preliminary scoping study focused on seven estuaries, not a comprehensive survey of all northern Australian coasts.
• The utility of the approach is demonstrated but not validated as an operational monitoring tool within the report.

Provenance

Source

Geoscience Australia Data

Collection Method

Satellite remote sensing analysis using the Landsat archive within the Digital Earth Australia platform.

Time Range

Time series spans approximately three decades, specific years not stated.

Freshness

Report last updated March 2026.

Geography

Seven estuaries in northern Australia: Darwin Harbour, Keep, Daly, Roper, Macarthur, Flinders, and Gilbert River estuaries.