Earth Notes: Rad Sounds: How Cool is your Home Heating in Time-lapse?

Hi, I'm Damon Hart-Davis, and this is the Earth Notes podcast for 15th September 2019.

I'm making rad sounds from my radiators and temperature data.

"Visualisation" is a way of displaying boring blocks of numbers in a form that we can latch on to and understand easily. We have millions of years' worth of pattern recognition and its ilk built into our brains by evolution.

[00:26]

I used to edit a supercomputing trade magazine many moons ago, and visualisation was a big deal then too. It's no use spending millions on your experiments and number crunching, if you can't actually get the results into your head or anyone else's!

Sometimes we use "visualisation" to make a pretty image, such as a graph.

Sometimes we can use other senses such as touch or taste or vibration.

Sometimes we can make sounds instead.

[00:55]

What happens if I speed up data from my house to listen to a year's worth of readings in a second?

That speeds up the daily cycle to happen 365 times in that second, or 365 hertz. That's between the F and F# above middle C. I end up using one sensor reading about every 12 minutes in each sound track that I create.

If we listen to (or look at) temperature or light or humidity we might expect not only to hear a daily cycle, but also a weekly cycle in many homes, and annual cycles driven by the seasons. Other fainter or messier signals may be there from Western (and other) calendar months. Maybe even something from the more-regular lunar cycles?

[01:45]

We can look for these mathematically with number crunching called Fourier analysis. But hearing or seeing could make for simpler believing?

I spent a few hours messing around and have some interesting initial results.

Nothing shocking but you can hear the difference between inside and outside temperatures, and inside between summer and winter.

[02:07]

Here is the sound of temperatures at my desk in the month of August just gone. The heating was not on. And temperatures changed especially smoothly while we were away at the end of the month.

[twice 201908-5s]

It's a fraction of a second, but there is a buzzy tone there.

Now here's the whole of 2018 temperatures from outside as captured by the sensor in our porch (4o). The porch is below the window on my room (5s). The sensors are thus only a few metres away from each other. Still a relatively smooth tone.

[twice 2018-4o]

And finally for today, the sound of my room (5s) temperatures for 2018:

[twice 2018-5s]

[02:54]

The buzzing at the beginning and end of the year is the heating (and Radbot) working to keep the rooms only heated when someone is active in them. So with much faster temperature movements than the basic daily cycle.

You can hear the effect of heating!

There's more on my "Earth Notes" Web site at Earth.Org.UK.