Where ocean noise pollution and ocean temperature intersect.

It was now a bit over 30 years ago that Steve Deutsch, a friend of mine and fellow musician called me up about a program he’d heard about where oceanographers were planning on broadcasting sounds across the Pacific Ocean to measure the temperature of an isothermal layer in the ocean which had been a consistent 4°C since the ice age. Called the SOFAR channel – for Sound Fixing and Ranging, the stated premise of the experiment was to monitor the temperature in the SOFAR channel, and see if, in fact, climate change was affecting the temperature of the sea.

Steve recruited me to offer comments at a public hearing about the proposal. At the time I was working in architectural acoustics, designing acoustical settings for museums and sound production facilities. I was the only person he knew who was informed enough about sound and acoustics to offer up qualified comments about the proposal. (This public hearing became the slow pivot that brought me to where I am now with OCR).

The basis of the experiment was to exploit the correlation between water temperature and the speed of sound in water – and that by projecting coherent sound through the SOFAR channel, speed distortions at the receiving end would express thermal states within the sound channel. There are a lot of things you can do if you can broadcast coherent sounds across ocean basins, but for the sake of this discussion, we’ll just stick with the thermal argument.

At the time the public was beginning to get concerned about climate change and global warming, and the fossil fuel industry had not yet coordinated their efforts to confuse us about it. The effort was called Acoustic Tomography of Ocean Climate, or “ATOC,” and the argument was that if the temperature of the SOFAR channel was rising, we’d know for sure that the ocean was getting warmer, and it would confirm the “speculations” about global warming.

The problem with this premise is that should the net thermal energy absorbed by the ocean overcome thermal inertia enough to raise the SOFAR channel by a measurable amount, the temperature rise would already be in thermal runaway.

We’ve detailed this before – whenever scientific papers come out about the thermal state of the ocean.  But a paper published earlier this month “with little fanfare” caught the attention of the BBC reveals thermal facts about the ocean that we can only call “alarming.” As I had speculated 30 years ago, the ocean may be in thermal runaway.

The question remains as to whether the fossil fueled industrial denial of our global climate catastrophe will abate, or if they will change their tune to “it’s too late to do anything about…”