Global Ionospheric Maps

Foundations of Amateur Radio

In the middle of the night when insomnia rears its head, there are occasions when an idea sprouts that is still with me the next day. I imagined a spinning globe that shows ionospheric propagation and allows you to navigate around the world and experiment. Think the ionospheric equivalent of windy.com in 3D.

To get to that point, I started off with the Australian Space Weather Forecasting Centre. I was on a roll when I discovered that under "HF Systems" it has a "Global HF" section with "Ionospheric Map", which, curiously enough, shows exactly what you'd expect.

What surprised me was that below the map is an animation viewer that allows you to see the last three days in half hour increments. Excitedly playing with this I found myself locked out and on the phone to the Bureau of Meteorology. I suspect that someone didn't tell the people who configured their content delivery network that users might be loading a gross of images from their website in short order, or two gross, if you also look at the "T-Index Map", like I did.

With no immediate solution on the horizon, I went on the hunt for other sources of maps and discovered the NASA/JPL-Caltech GUARDIAN project, described as near-real-time ionospheric monitoring software for natural hazards warning.

Their website has a limited archive of daily videos showing how the ionosphere changes, which was exciting until I discovered that my computer wanted to download each one, rather than play them in the browser, so making lemonade, I downloaded all of last month, thank you "curl", used my favourite video editing tool, "ffmpeg", to combine them, then uploaded the result to my VK6FLAB YouTube channel for our enjoyment.

What's fascinating to me is being able to see, for the first time, just how the ionosphere changes throughout the month. You can see where there's regular solar activity and where exceptions occur. I'll note that there's a few gaps, I suspect that the software behind the scenes at JPL had some outages, but what's there is what was available.

Now for the interesting stuff.

This data is not created by something monitoring in space at L1, or in orbit around Earth, it's created by ground stations scattered around the planet. GUARDIAN is based around the Global Navigation Satellite System or GNSS. The project, to give its full name, the GNSS Upper Atmospheric Real-time Disaster Information and Alert Network, uses the radio signals from the four navigation constellatio