Storm chasers: Hunting for the prefect wave to assess defence values of coastal ecosystems

For most ecologists this time of the year (autumn and winter) serves as a reflection period. Data of the previous growing season is analysed, papers are written and new experiments are planned for during the next growing season. However, a small group of ecologists from the UK and the Netherlands have made different plans this year. They are very busy chasing storms!


To develop sustainable and more robust coastal defence schemes, new adaptive strategies for mitigation are necessary. The wave attenuation properties of coastal ecosystems might play a key role in coastal defence. To estimate the defence value of various coastal ecosystems, it is necessary to measure how much wave energy is dissipated. Coastal ecosystems such as saltmarshes, seagrass meadows, mussel beds, or reefs of oysters and honeycomb worms, all have the potential to dissipate wave energy and can be used for this purpose. However, for many of these ecosystems hard field measurements under natural (stormy) conditions are lacking. To fill this knowledge gap no efforts are spared within the THESEUS project.


Ecologists of Bangor University (BU) and the Royal Netherlands Institute of Sea Research (NIOZ) teamed up to rise to the challenge. They planned to measure wave attenuation over saltmarsh-mudflats of various geomorphological configurations and over other coastal ecosystems. However, due to technical failures, the first storm season within THESEUS was missed. Only a few pilot measurements could be done, and these revealed teething problems with the equipment. As a consequence the team did not (yet) meet the required deliverables. Fortunately, the second storm season provides the team more opportunities to catch storms and to make good measurements.


Deployed pressure sensor for measuring wave attenuation on a mussel bed (photo by Jim van Belzen)

During this new storm season, efforts were divided between the two research groups. BU is measuring wave attenuation over various marsh-mudflat configurations in Wales and Scotland. At the same time, wave measurement devices are deployed over mussel beds, oyster reefs and salt marshes in the Wadden Sea and Scheldt estuary. By separating the two teams to work at different regions, they hope to double their chances of catching the perfect wave. In order to meet the required number of measurements by the deadline (spring 2012), still quite some field setups have to be deployed, but it appears that the weather gods are finally smiling upon the team and the equipment seems to be functioning properly as well!

At the moment of writing, over half of the scheduled work was finished. So things are heading in the right direction.


Let’s chase some storms!


By Jim van Belzen