The study of the seafloor derived from satellite imagery continues to advance and improve. A new scientific study has verified the effectiveness of a methodology developed to obtain bathymetric data in the western Mediterranean, based on what a satellite sends. The result of this work, published in International Journal of Applied Earth Observation and Geoinformationreaffirm the value of this tool for monitoring coastal areas with different levels of turbidity and different seabeds.
The research was carried out in Cala Millor (Mallorca), an ecosystem of great importance for its marine biodiversity, but also for its potential vulnerability to the effects of global change. The researchers were able to accurately map its coastal bottom from images from the Sentinel-2 satellite. It is the first time that this methodology has been tested in an area with the presence of Posidonia oceanica, an aquatic plant endemic to the Mediterranean and of great ecological value.
It is the first time that this methodology is applied in an ecosystem with the Mediterranean plant ‘Posidonia oceanica’
The work was carried out as a result of a collaboration between researchers from the Institute of Marine Sciences of Andalusia (ICMAN-CSIC), the Coastal Observation System of the Balearic Islands (ICTS-SOCIB) and the National Office of Oceanic and Atmospheric Administration of the United States. (NOAA).
“This type of tool is an invaluable support for the management of coastal zones, as they offer up-to-date and continuous information on the morphodynamic changes that occur in them. They are very useful to help managers in decision-making and to define effective adaptation measures in the face of the effects of global changes, achieving a more resilient coastline”, explains Sandra Viaña-Borja, ICMAN-CSIC researcher, in the note releasing the results. their discoveries.
Bathymetry, decisive in maritime strategies
In this way, satellite-derived bathymetry (SDB) goes a step further to consolidate itself as an alternative to traditional bathymetric techniques that are performed with aircraft or ships. The main advantages of satellites are that they make it possible to study the coastal floor with greater spatial coverage and free of charge, without the need to be present in the area or carry out an expensive deployment.
However, despite the great advances achieved in recent years, the researchers’ main challenge is to demonstrate that these models can be efficiently and accurately replicated, globally and operationally, regardless of the characteristics of the area.
This technology could facilitate measures to achieve more resilient coasts
This methodology had already been used with very favorable results in other regions of the planet, such as the east coast of the United States and the Caribbean. Now it has been evaluated in a different ecosystem, the Mediterranean, where the Majorcan beach of Cala Millor is one of the most monitored by the ICTS-SOCIB Comprehensive Beach Monitoring System, which has been in operation since 2011.
Likewise, given its importance, the European Commission recently approved the grant for the LIFE AdaptCalaMillor project, with the aim of promoting the adaptation of this beach to climate change and increasing the resilience of infrastructures, ecosystems and services.
Generating detailed maps of underwater topography is essential to support a wide range of near-shore activities such as dredging, environmental management, pipeline and communication cable routing, infrastructure maintenance, hydrographic applications, navigation, freight transport, aquaculture and fishing, research, tourism or recreational sports.
It should be noted that bathymetry is one of the key characteristics for the elaboration of Maritime Strategies, in accordance with the directives of the European Commission. This instrument constitutes the general regulatory framework to which the different sectoral policies and administrative actions with an impact on the marine environment must adhere.
“We are currently evaluating these tools in other regions, such as Galicia, South Korea and Alaska, where we have obtained promising results. It is important to highlight that, according to the International Hydrographic Organization, more than half of the shallow bottoms of our oceans remain unmapped or out of catalogue. Satellite-derived bathymetry is a free and easily accessible technology. It is undoubtedly the future of coastal monitoring”, highlights Isabel Caballero de Frutos, ICMAN-CSIC researcher.
Reference:
Caballero, I. et al. “Semi-automated bathymetry using Sentinel-2 for coastal monitoring in the Western Mediterranean”. International Journal of Applied Earth Observation and Geoinformation (2023)