Derived data product DEA Intertidal Extents

  • See where tidal zones begin and end

  • Understand coastal habitats

  • Based on three decades of Landsat data

red, yellow and blue illustrated overlay along curved coastline image as captured by satellite

Define a fluctuating world

Understanding the boundaries of the ‘intertidal zone’ — the strip of coastal land revealed and concealed daily by ocean tides — has long been a challenge. Digital Earth Australia (DEA) Intertidal Extents gives definition to complex and ephemeral landscapes

coastal rock pool with small crab on rocky edge

Intertidal zones include critical habitats such as mudflats, seagrass beds, sandy beaches and rocky shores. They’re a literal pool of nutrient-rich organisms and critical bird and sea life

red and yellow illustrated overlay along complex coastline image as captured by satellite

The dataset provides information on the lowest (LOT) and highest (HOT) observed tides for a chosen geographic cell, revealing the satellite-observed tidal range (HOT-LOT) for any given location

Why map intertidal extents?

  • Get insights into unique costal habitats

  • Contribute to studies of key and threatened coastal species

  • Understand the topography of the intertidal zone

  • Inform geomorphology and hydrodynamic modelling

Fiddler crab on muddy ground with orange pincer raised

Imagery for impact Welcome to the intertidal zone

Anyone who has peered into tidal pools or chased crabs on tidal flats knows the intertidal zone represents a rich ecosystem. Now, thanks to three decades of Landsat data, DEA researchers have mapped the intertidal zone map for the entire Australian coast

Related resources

Satellite image of coast with colored edge lines and area marked in red box A

Journal article

‘Extracting the intertidal extent and topography of the Australian coastline from a 28 year time series of Landsat observations’

Journal article Read the paper
Coastal bay at night with lights from town reflecting on water

The “Z” of where land meets sea

The Digital Earth Australia team have created the first 3D model of Australia’s entire coastline

The “Z” of where land meets sea Learn more
Green and white sandy landmass protruding from blue ocean

Our suite of coastal products

DEA Coastlines, DEA Intertidal Extents, DEA Intertidal Elevations, and DEA High and Low Tide imagery provide new perspectives on critical coastal environments.  

Our suite of coastal products Browse the products