Many thanks to Hamilton (KD0FNR) who writes:
Hamie (KO6BTY) and I have been playing with mapping our QSOs for a few years now. We evolved from ionosonde data and Google Earth to data from an NOAA model called GloTEC, (Global Total Electron Content), and Cesium Ion maps. Out of that, we have an app up and running that provides half hour in the past global values for hmF2, (height of the F2 layer at the maximum electron density), and foF2, (the frequency a vertical signal will still be reflected back at.)
The app pulls data from GloTEC, runs it through an open-source data tool called Datasette that uses a plugin we wrote to turn the data into a CZML file that can be viewed with a Cesium Ion map. We use Cesium’s free site, Cesium Sandcastle, to display the map on our page.
The app is at
https://copaseticflow.blogspot.com/p/project-toucans-current-f2-map.html
The code is at
https://github.com/hcarter333/glotec_hm_fo_f2
Here are a few screen shots:
The grid squares are color coded on the foF2 scale. The ‘spires’ are color coded on the hmF2 scale and extend upwards to each spires’ corresponding hmF2 height in km.
The map is hosted though github and Cesium Sandcastle at no cost to us on our blogger.com domain blog. Users can view the most recent GloTEC data for their area by exploring the map.
If you have any feedback, we’d love to hear it.
Thanks Thomas!
What a clever way to visualize this F2 data! You’re such an innovative father/daughter combo! Readers, they welcom your feedback!
Fantastic work to quickly identify propagation conditions with new data points represented in a visual way
Complimenti!🫡👏🏻👍
Looks like 60m is in NVIS range. ….off to the radio
John ve3ips
Thanks John! That’s super-cool that it’s useful! We’re working on getting maximum usable frequency onto the map soon.
I love this kinda stuff! Fantastic!
TU 72 de W7UDT ID sk ee
We’ve been having a blast playing with all the GIS things that are possible now.
TNX de KD0FNR es KO6BTY
Wow! What a tool… Brings the textbook theory into a practical tool. Now I have to get smarter to be able actually USE the data.
🙂 Hey Steve! Thanks for the yearly, October POTA QSOs to Cibola National Forest!
We did actually find a good text book on this. The Department of Commerce published “Ionospheric Radio Propagation” by Kenneth Davies in 1965.
What’s the significance\importance of Cesium ion to HF propagation or the foF2 or hmF2 ?
Thanks and 73,
Bob WK2Y
Good morning Bob!
Cesium Ion is the earth mapping platform. I hadn’t thought about the name (Ion) and how that does actually sound related to an F2 map. Ion is what Cesium, (a 3D geospatial mapping company out of Philadelphia), decided to name their web capable mapping product.
We’re using Cesium because we can make 3D maps for free. We don’t have the code ready to go for wide release yet, but we can map our 20 meter QSOs on the same map using hmF2 as the top vertex of a triangle between stations so we can visualize the approximate path the radio waves took.
With the data that we can see on the map, we also figured out why our rig seems to get stuck behind the Rockies from about 10 AM PST until the sun starts to go down every day. It wasn’t that the F2 height was coming down, it was because the critical frquency, (fof2), went up making the F2 a better reflector that was popping our RF right back down into Utah. Once the sun starts going down, the critical frequency, fof2, starts to reduce as well. At that point, our 14.0574 MHz refracts higher into the F2 layer and we routinely make coast to coast QSOs.
Thanks for the great tool. What is the unit of the hmF2, is it km (kilometer)? Its Legend doesn’t show unit.
Currently all hmF2 spires seem having the same lengths (heights) around the globe. In addition to color coded, is it possible to plot the spires as different lengths (heights), proportional (or more exaggerated) to their calculated data? That will be intuitive.
Thank you and 73!
Thanks Jun! You make a very good point about the units. They’re in km for hmF2. I’ve modified the legend to reflect that.
The spires are different lengths, it’s just difficult to tell because the optical difference between 247 km and 509 km (the hmF2 range while I’m writing this), is about 250 km, and the radius of the Earth is on the order of 6,300 km.
There is a way to make the difference visible though! In the upper right hand corner of the map there are a few Cesium controls. If you click on the one that looks like a wire frame globe, you’ll be given three selections. If you then choose the one that looks like a plane in perspective, you’ll get the globe projected onto a plane. By holding down Ctrl and dragging with your left mouse button, you can tilt the plane back. After that, if you zoom in on one of the bubbles on the hmF2 map with white spires, you should be able to see a difference in the sizes of the spires.
To see an example, take a look at the issue I opened to document this:
https://github.com/hcarter333/glotec_hm_fo_f2/issues/3#issue-2901722276