Acoustic Surface Elevation Dynamics data Marconi salt marsh

At the semi-natural
constructed Marconi salt marsh, bed level change data were collected using
state-of-the-art Acoustic Surface Elevation Dynamics (A-SED) instruments. This recently
developed instrument measures the distance between the bed and the instrument
through the echo of an acoustic signal. The instrument is set-up to be able
to collect measurements when the sensor of the instrument is fully inundated. A
burst of eight samples (sampling frequency of 5 Hz) was stored at a measurement
interval of 5 to 15 minutes. The instruments were installed downward looking,
with the sensor head aimed vertically at the bottom. The instruments were serviced,
cleaned and data were downloaded every two to three months. A post-processing
script was developed in Python to convert the acoustic return signals to bed
level change data. The measurements were validated with manual readings of the height
above bed (HAB) of the sensors every time the instruments were serviced.