The Wadden Sea is a dynamic coastal ecosystem characterised by broad intertidal flats that are exposed at low tide and submerged at high tide. Exposure time is an essential input parameter for ecotope mapping; the classification of ecological zones based on abiotic factors.

While the interplay of wind, tides, and sediment dynamics has been studied, there remains limited understanding of detailed exposure times, areas and flow patterns under varying wind conditions, particularly in shallow intertidal zones of the Wadden Sea.

This study quantifies how variations in wind direction and magnitude affect exposure characteristics and flow patterns on the Pinke Wad, located between Ameland and Holwerd. A 3Di-calibrated subgrid model, which is well suited for very shallow areas, is used to simulate twelve wind scenarios in addition to a base case without wind. The effects on one tidal cycle are analysed.

The scenarios result in different hydrodynamic responses on flooding and drying. Easterlies cause a non-linear increase in mean exposure time, from 3.67 h in the baseline to 5.51 h under an East-9 storm (≈ 23 m s-1). By contrast, westerly and northerly winds shorten exposure almost linearly for the simulated scenarios: the mean exposure time decreased to 0.95 h (North-9) and 0.77 h (West-9), with exposed area decreasing by 70–82%. A northerly wind of 6 Beaufort decreased exposure on higher flats by up to 49% (∼6 h), whereas an easterly of the same force increased it by 20% (2.5 h). Residual currents responded accordingly, easterly winds reversed the net flow westward from Beaufort 3 onwards. Westerly winds generated the strongest eastward residual currents. Northerly winds also induced westward flow starting from Beaufort 3, though with smaller directional shifts. Wind-driven changes in exposure time and changing flow patterns have clear implications for ecotope mapping, because there is a large variability over time.

The results highlight the substantial and spatially important role of wind in changing hydrodynamics on the Wadden Sea’s intertidal flats. By linking variations in wind speed and direction to changes in residual flow and exposure patterns, the findings provide a better understanding of hydrodynamic-ecological interactions. The use of a (well-calibrated) hydrodynamic subgrid model may offer a promising way forward for calculating exposure times as input for ecotope mapping compared to the current method, which relies on interpolation on water levels between gauge stations.

The Hai Phong region is undergoing transformative changes through a Masterplan aimed at enhancing financial stability and improving the quality of life for the local community. A significant component of this Masterplan involves the construction of two new port terminals close to the mangroves of Do Son, a small town southeast of Hai Phong. Mangroves are beneficial in multiple facets. They act as a natural barrier, protecting coastlines from erosion, storm surges, and tsunamis. Additionally, mangroves contribute to water quality by filtering pollutants and trapping sediments, improving overall aquatic ecosystems. Furthermore, they provide crucial habitat for various species, supporting biodiversity and serving as nurseries for many marine organisms that benefit the local community. This research investigates the potential implications of the Masterplan using the following research question: What are the potential effects of the Hai Phong Masterplan on the mangrove ecosystems and the local community? Conducted by a multidisciplinary team of six students, this research involved interviews with professionals, locals, and governmental organisations, extensive literature review, and field trips. It was concluded from this research that the construction of the port terminals have far-reaching consequences. In the mangrove area in Bang La (area A), the port terminal will have a sheltering effect over the mangrove area. This will cause sedimentation to occur and thus accretion. Also, it is also expected that the water quality will degrade further due to increased anthropogenic activity in combination with the poor sewage system present. The mangrove area in Ngoc Hai (area B) is expected to have little direct changes. The local community in Do Son shows varied awareness and support for the Masterplan, with stronger support in mangrove area A. Economic benefits, such as increased tourism, drive positive attitudes. However, there is a notable lack of awareness in area B. The willingness to participate is influenced by economic incentives, and effective communication is crucial for shaping community perspectives. With regards to the further execution of the Masterplan it is recommended to incorporate effective waste management, revise reafforestation plans to meet legal obligations, and engage key environmental stakeholders. For further research, it is recommended to conduct measurements over a more extended period of time to better understand the dynamics of the area. Additionally, more detailed research is needed to substantiate assumptions.