National Oceanography Centre (NOC) (GB)
Intertidal zones form an interface between land and sea. They are important features of the coastal landscape providing a multitude of ecosystem services and forming a critical habitat for a wide range of species. Satellite Earth Observation (EO) unlocks new capabilities for monitoring intertidal zones, which are under significant pressure from multiple sources including coastal development, impacts from upstream land use and changes in sea level.
The unique capabilities of EO for intertidal mapping have been demonstrated by research groups such as Murray et al. who, using optical data from the Landsat archive, have shown a declining trend in the global extent of intertidal flats. To meet the higher spatial and temporal monitoring needs of regional and local authorities the UK National Oceanography Centre (NOC) have developed a new approach based on S1 SAR (Synthetic Aperture Radar), making use of temporal waterline methods (TWL).
This time domain, or per pixel approach, reduces the manual interpolation steps inherent in optical methods and unlocks a new and unique way of observing intertidal dynamics. The work builds on nearly two decades of research into environmental monitoring with X-Band Marine Radar , complementing the synoptic and temporal frequencies that in-situ radar monitoring provides .Following two years of development and demonstration carried out in partnership with the Channel Coastal Observatory, the Environment Agency, Wales Coastal Monitoring Centre and local authority programmes, this new project will enable further development of the methods and the processing software.
The objective is to enable more widespread access to this innovative method, with inherent potential for long term monitoring of intertidal dynamics at local to national scales. Previous development work was carried out as part of the Atlantic Region Initiative, under the Blue Economy, Marine Spatial Planning and Innovation Clusters project.
Video shows intertidal elevations for Morecambe Bay, from January 2017 to August 2022. At 310km2 Morecambe Bay is the largest intertidal area in the UK.