Tag Archive: hydrophone

Yosemite’s Frozen Lakes

For all interested in ice sounds: check the blog “music from the ice” by composer Cheryl E Leonard. She recorded some beautiful sounds from frozen lakes in Yosemite National Park and used very similar equipment to my hydrophone recordings of ice sheets. Cheryl also invents astonishing instruments and travelled to Palmer Station in Antarctica, the field recordings of this trip were released on a CD called “Chattermarks“.

The Dümmer See, a lake in Germany’s Lower Saxony close to where I was born, suffers from heavy nutrient pollution. During spring and summer, the lake is full of blue-green algae or cyanobacteria and it is frequently forbidden to swim in the waters. This is caused mainly by two factors: to prevent floodings the lake is surrounded by dykes which takes the possibility to filter the shallow waters and results in silting. The second factor is massive cattle farming in the area around the lake, one of the most extensive in Central Europe. The liquid manure accruing from this is distributed on the farming land to grow crops and large amounts of it eventually ends in the Dümmer See. It is estimated that 30 tons of phosphorus every year is spilled into the lake depriving fish and other organisms of oxygen.

Last year I dunked my hydrophone into the green, muddy water of the lake to see if I can hear anything at all. Surprisingly I found a constant chirping that was onmipresent in the lake, I heard it everywhere I put my underwater microphone in the waters, even in ditches around the lake. I have no idea what species this is, I guess it must be a small water bug that seems to find perfect conditions in the polluted lake. This example is a close-up of one bug I recorded from a jetty in Lembruch. The other sounds come from the waves lapping against the jetty.

The hydrophones of German Alfred-Wegener-Institut recorded an iceberg crashing into the ice shelf close to the Neumayer III station in Antarctica on 11th Feb (German report about it here). The incident went unnoticed by the crew on the station even though the crash caused a 2 km crack in the ice and destroyed a supply road. It was a German scientist in Bremerhaven who monitored the audio live stream from the Palaoa underwater microphones to figure that something was wrong. He heard a loud growl from the hydrophones and informed the staff at the station. An excerpt of the collision can be heard on this German news site. There are several other underwater noises that occasionally occur in Antarctica, some are collected on this site of the Alfred-Wegener-Institut. And you can still listen live to the antarctic underwater world at home here.