Students from the School of Ocean Sciences at Bangor University, UK, have a 30-year tradition of heading to the Laugharne estuary in south Wales each summer to investigate the sediment dynamics of this energetic environment. Nortek’s innovative Doppler instrumentation is now helping the students to understand the processes behind the sedimentation, while gaining valuable skills for future employment.Read more
Survey data, collected by successive generations of students over this period, indicate that the estuary is infilling with fine marine sand at a rate of 1–2 cm per year.
The sediment transport results primarily from strong asymmetric tidal currents causing the influx of sand from Carmarthen Bay on the dominant flood tide.
Additionally, locally generated wind waves in the shallow estuary may contribute at different frequencies and complicate the overall picture. A newly introduced exercise utilizing Nortek’s Doppler instrumentation is helping the students to understand the processes behind this long-term trend in sedimentation.
“We are utilizing a Nortek Vector Doppler velocimeter, together with an externally mounted optical backscatter sensor (OBS) and a pressure transducer (PT) to illustrate the temporal patterns of sediment flux to the students,” says Dr Martin Austin, lecturer in coastal sediment dynamics at Bangor University.
Image 1: Martin Austin (left) explaining the Doppler principles and the operation of the Nortek Vector for measuring the suspended sediment flux in the shallow Laugharne estuarine environment.