Highlighted talks

The AquaBreak Project aims at creating the AquaBreak Offshore System (AOS) to explore the synergies of seaweed aquaculture systems on food production and coastal protection in Portugal, which is a country particularly exposed to the maritime harsh conditions. The objective of the current study is to assess the wave damping potential of seaweed aquaculture systems exposed to the common conditions of the Portuguese Coast in order to create an effective implementation plan of the AOS. The experimental campaign was performed at wave flume of the Hydraulics Laboratory at Faculty of Engineering of the University of Porto. A longline seaweed aquaculture physical model was built using nylon lines with polyurethane sheet stripes. The wave characteristics were measured upstream and downstream of the model using resistive wave probes. The results revealed that the presence of a seaweed aquaculture systems can decrease the significant wave height by 35% for the tested conditions. 

Permafrost coastlines represent a large portion of the world's coastal area and these areas have become increasingly vulnerable owing to the changing climate and its strong dynamics observed over the past decades (Irrgang et al., 2022). The predominant mechanism of coastal erosion in these areas has been identified through several observational studies as thermomechanical erosion-a joint removal of sediment through the melting of interstitial ice (thermal energy) and abrasion from incoming waves (mechanical energy). This work provides an overview over novel avenues that are useful for a better understanding of processes and interactions of ocean waves and Arctic coastlines. The work presents some of the recent erosional observations from a cold room and wave flume setup as well as micro CT measurements. We report common pitfalls, and provide recommendations for the developments that are required of the community to better facilitate future experimental work to understand the physical processes.

Live-bed scale models of estuaries have long been impossible due to unwanted scale effects. Especially generating tidal flows and sufficient sediment mobility as in estuaries proved challenging, in contrast with meandering and braided river scale experiments where gradient could be increased to obtain sufficient mobility. Here we present 1:2000 scale experiments of estuaries with self-formed, dynamic channel-bar patterns in sand. Tidal currents were obtained by periodic tilting. In contrast with predictions from classic Froude and live bed procedures for scale models, the experiments produce bar morphologies closely resembling natural systems such as the Western Scheldt. Various scale effects were avoided by using poorly sorted coarse sand. With the advantage of experimental control, effects of fairway dredging and dumping could be tested and were shown to have large effects on intertidal habitat. The novel experimental setup, called Metronome, now allows a large variety of tidal system scale models.