Tidal Excursion

General Information

North Sea

Baltic Sea

Clyde Marine Region

Adriatic Sea

Eastern Mediterranean Sea

Tidal Excursion

Layer Info
Category	Governance
Sub-category	Environmental Conditions
Editable	No

Description

Tidal excursion refers to the average distance a water particle travels between low-water slack tide and high-water slack tide during a tidal cycle. It measures how far a body of water moves back and forth due to tidal currents.

This phenomenon is influenced by various factors, including tidal phases, bathymetry and local geography. This is important to take into account when planning activities that will change the bathymetry, such as dredging and sand and gravel extraction. If the area affected is larger than the tidal excursion, there are high chances that stratification will occur, limiting gas exchanges with the atmosphere which can cause eutrophication.

In some locations, such as in the English Channel the tidal excursion can be around 18 kilometers. The tidal excursion length is site-specific and depends on the characteristics of the location.

MSP Challenge

In the MSP Challenge, the tidal excursion layer is not editable, but allows players to get insight into water movement and adjust their sand and gravel extraction strategies accordingly.

This datalayer is an output of the OR ELSE project and is available in the Sand Extraction Edition and in the Digitwin Edition.

Sand Extraction Edition

Types

• 0 - 4 km
• 4 - 6 km
• 6 - 8 km
• 8 - 9 km
• 9 - 10 km
• 10 - 12 km
• 12 - 18 km

Metadata

Data Source

This layer was provided by partners from the ORELSE project.

Creator: Mohammad Daliri (NIOZ).

Original Title

Tidal Excursion Map - Southern North Sea - April 2025

Description

This dataset represents the spatial distribution of tidal excursion (in kilometers) on the Southern North Sea.

Derived from GETM (GeneralEstuarine Transport Model) simulation outputs, forced by ECMWF ERA-5 meteorology, TOPEX-POSEIDON tides, NOOS bathymetry, and ORAS4 temperature/salinity boundaries.

Creation Date

04/2025

Methodology

The original file type was NetCDF.

1. Extracted lat, lon, critical_depth variables into csv through python script.
2. Csv to points, reprojected and cleaned data (empty points far outside study area)
3. Preformed TIN interpolation
4. Clipped raster to mask based on the extent of original points
5. Reclassified by table

Not applicable.

This layer is not available in the Baltic Sea Edition.

Not applicable.

This layer is not available in the Clyde Marine Region Edition.

Not applicable.

This layer is not available in the Adriatic Sea Edition.

Not applicable.

This layer is not present in the Eastern Mediterranean Sea.