The graph below shows how pressure varied over the two week trial at 3 of the sensor sites. The y-axis is not calibrated, the true depth of sensor 1 was 3-5m and the true depth of sensor 6 was 9-11m. The variation corresponds to tides ebbing and flowing. Sensor 3 had a range error, cuased by sliding down the sandbank to a greater depth than expected (needs an autocalibrate fn next time).

The next graph (below) shows radio performance over 24 hours - the performance degrades at high tides, because the waves are bigger, and obscure the aerials more often