30 September 2008

Sonification of tides

To say that this post is relevant to the content of Science, civilization and society is stretching credibility, but it has some entertainment value and is related in some way to the discussion of tides in my blog "The tide predicter of the U.S. Coast and Geodetic Survey" of 25 May. In that post I referred to a web page with an animation of Kelvin's Tide Predicter. The same page has a link to "Tidesounds", where tidal constituents are used to produce "musical scores." You can listen to some examples here: Miami harbour entrance, Daytona Beach, Florida, Cordova, Alaska.

The Tide Predicter page says that "the musical patterns were generated by Stephanie Mason at the University of Minnesota Geometry Center, who wrote C-code to generate predicted tides for these ports, and programmed a NeXT-MIDI interface to generate the corresponding soundtracks." You have to admit that the resulting sounds are more of educational/scientific than musical interest. I asked my son Sebastian, who studies music technology at the University of Adelaide, to produce a bit of sonification of some observational data from one of my field studies. He used data from an oceanographic data buoy that recorded (among other things) wind speed and direction, ocean current and temperature and conductivity at various depths in Thorny Passage near Port Lincoln, South Australia. Here is the result: Southern Ocean sounds.

Seb used the observed wind direction to set the rhythm and the battery voltage to control the loudness; he converted the conductivity at 2.5 m depth into marimba, the temperature at 2.5 m depth into soft organ and the salinity at 2.5 m depth (calculated from temperature and conductivity) into drums. As the water moves in and out through the Passage with the tide its salinity and temperature change slightly, so the up and down of the melody mirrors the tide. The variable speed of the rhythm is produced by the passage of atmospheric fronts that cause sudden changes in wind direction. It does make for more interesting music than just tidal heights from a tide table, don't you think?

You can find Seb's own blog here.

19 September 2008

The beginning of marine science

In Lecture 26 I said that "the first of the great deep-sea expeditions was undertaken by the British naval vessel Challenger in 1873 - 1876. This was the beginning of the race for the last territories still available for colonization." This correct but somewhat general statement does not explain why research voyages to other continents had to start with the exploration of the greatest ocean depths. The 20-year birthday volume of Oceanography, the official journal of the international Oceanography Society, has just come out and supplies the answer:
The introduction to the "Summary Report on the Scientific Results of the Voyage of the H.M.S. Challenger" of 1895 says: "The desire to establish telegraphic communication between Europe and America gave the first direct impulse towards systematic exploration of the deep sea." (Briscoe, 2008) It appears that again science - in this instance deep sea science - develops only where there is a need for it.
The same Oceanography volume contains an article that documents in detail how after World War II physical oceanography was driven by the needs of imperialist navies to develop underwater warfare. (Munk and Day, 2008)


Briscoe, M. (2008) Celebrating 20 years of The Oceanography Society. Oceanography 21(3), 12-13.
Munk, W. and D. Day (2008) Glimpses of oceanography in the postwar period. Oceanography 21(3), 14-21.

08 September 2008

Science, Civilization and Society: the book is out

As announced earlier, the book version of "Science, Civilization and Society" is now available. It can be ordered by referencing the international book numbers

ISBN-10: 363906593X
ISBN-13: 9783639065930

It can also be ordered online from various sellers. Some are listed at the web site "World Civilizations"; just click on the title of this post. It may be worth comparing prices at other sellers - the steep price was set by the publisher, not by me. As of today the lowest price is only available in Europe, unfortunately.