Antonio Della Marina About Projects Soundworks Media Just intonation Agenda
Pulse
25 years of ocean tides (2015)

sound work
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We experience the motion of the tides because we see it with our eyes. Their cycles are too slow to be perceived as sound, but the rising and falling mass of the sea displaces the air in the same way as a huge loudspeaker. In order to hear the sound it produces, I speeded up the reading of the data collected in the last 25 years from two of the longest-lived oceanographic stations on the planet: that of Honolulu in the Pacific and that of Rodrigues in the Indian Ocean.

What in reality happens with an approximate frequency of twice a day - the peaks of high or low tide normally occur every 12 hours and 25 minutes - I have reproduced at the frequency of 60 oscillations per second. I have increased the reading speed of the measurements by about two and a half million times, so that 25 years of tide have been reduced in about 5 minutes.
Over the fundamental frequency of 60 Herz you can hear a regular pulsation that corresponds to the most accentuated tides that occur at each change of the moon (every 28 days in reality, twice per second in the audio file).
The disturbances are due to missing data packets or traumatic events, while the background noise corresponds to the variations that distinguish the real world from that of the mathematically calculated models of the astronomical tide.

This process of transforming data into acoustic elements is called sonification and is applied in the scientific field for informational purposes or to investigate the nature of things and their interrelation.

Left channel
Honolulu-B, Hawaii
Latitude: 21 18.4N
Longitude: 157 52.0W
Country: USA

Right channel
Rodrigues
Latitude: 19 40.1S
Longitude: 063 25.1E
Country: Mauritius

Notable episodic events
28 Feb 2010: Tsunami from Chile (4'01" left channel)
11 Mar 2011: Tsunami from Japan (4'13" left channel)

Data source
The Global Sea Level Observing System (GLOSS)

Sonification data
number of hourly measurements: 219'144
interpolation: 60 values every sample
Sampling frequency: 44100

 


Technical rider
- stereo audio system or headphones
- oscilloscope

Thanks to
NOAA Climate and Global Change program
University of Hawaii Sea Level Center