Play Me a High C

The world is like an apple whirring silently through space

Monday, November 4, 2024 · 1 min read

After a chance conversation at our lab retreat, I got curious about what tides “sound” like. I downloaded the NOAA’s water level data for Boston Harbor from the start of my PhD until today and sped it up by a factor of about 200 million.

You can clearly hear the tone representing the daily tides (pleasingly, it’s tuned to “middle C”… get it?). The vibrato or “beating” is caused by the difference between the solar and lunar constituents, and corresponds to the semimonthly spring/neap tides. Finally, if you speed it up even more, you can hear three annual “scrapes” corresponding to yearly variation (caused by the Earth’s axial tilt?).

◊ ◊ ◊