The Observatory in Galway Bay is an important contribution by Ireland to the growing global network of real-time data capture systems deployed within the ocean. Installed on the seafloor 1.5km off the coast of Spiddal, the observatory uses cameras, probes and sensors to permit continuous and remote live underwater monitoring. Data relating to the marine environment at the site is transferred in real-time from the SmartBay Observatory through a fibre optic telecommunications cable to the Marine Institute headquarters and onwards onto the internet.

This dataset comprises of processed acoustic data that has been collected from the Galway Observatory site using an icListen HF Smart Hydrophone – a digital hydrophone that processes and stores acoustic data. The dataset comprises of processed data, collected from the Galway Bay Subsea cabled observatory since its installation in 2015.

The wide frequency range hydrophone is installed on a separate lander approximately 30m away from the EMSO Smartbay Cable End Equipment Node in Galway Bay in approx. 25m depth of water @ 53° 13.640'N 9° 15.979'W.

The processed FFT files are stored in a txt file generated once a minute with a reading every second. The metadata is included in the header of the text file. TXT files contain ASCII variables separated by tabs. These files may be read by virtually any text editor or spreadsheet program. When interpreted as tabular/spreadsheet data, tabs are equivalent to column divisions, and newline characters are row divisions. All TXT files generated by icListen/Lucy contain several rows of header information at the start of the file, followed by rows of either FFT data or time series data. icListenHF stores only FFT data in TXT format.

Practical uses of this dataset includes but are not limited to scientists, researchers and marine technologists involved in the areas of marine mammal monitoring, real-time noise measurement, environmental assessment and improving compliance with the Marine Strategy Framework Directive. The processed files are available in real-time via: http://smartbay.marine.ie/data/hydrophones/