Help understanding how to look for evidence of TIDs in WSPR data

[Isobel Smith - 2E0YSI]

Hi all, 

I would like some help in understanding how to look for evidence for Travelling Ionospheric Disturbances in WSPR data. For context, I am interested in looking at the changes in radio propagation after a space shuttle launch (due to the Travelling Ionospheric Disturbances caused by the launch). 

The problem is, that I am not actually sure how to look for the evidence of TIDs in WSPR data. How I understand it, the travelling ionospheric disturbances affect the density of electrons in the ionosphere, so the effect on HF propagation can be enhanced, or weakened (more fading). Is it "enough" when we would observe some fading or enhanced propagation in the data?

Is just looking for abnormalities in the wider pattern good enough, or is this not the correct way to try to decipher the WSPR data? Should I limit the results to those below 3000km in distance, or is it okay to include multi-hop transmissions as well?

Thank you so much for reading through my email, any help, comments, or observations is much appreciated, I will include more information that I couldn't fit into this message below,

Thanks

Isobel Smith,
73 de M5DUK 

[ghby...@k9trv.org]

Dear Isobel,

 

I would think that to be a very difficult task.  There are no more space shuttle flights or launches, and when there were, there was not a wide and deep WSPR network, with the current level of multiband WSPR transmitters (often Turn Island Systems ‘wsprsonde’ units), nor multiband WSPR receivers (‘wsprdaemon’, often based on the Rx888 SDR device.)

 

The last shuttle flew in July of 2011.

 

73,

George K9TRV

--
Please follow the HamSCI Community Participation Guidelines at http://hamsci.org/hamsci-community-participation-guidelines.
---
You received this message because you are subscribed to the Google Groups "HamSCI" group.
To unsubscribe from this group and stop receiving emails from it, send an email to hamsci+un...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/hamsci/0979845d-b5bb-45f0-af81-6d1d3a55e953n%40googlegroups.com.

[Isobel Smith - M5DUK]

Thank you for your reply. Perhaps "Space Shuttle" is the wrong terminology - I just meant any kindof spacecraft launch (e.g SpaceX launches). For example,  I initially just took the naive approach, of looking at the WSPR beacon data, with transmitters located around the site of the launch. As the locator for the Vandenberg Space Force Base in California is DM04AR, I decided to look at transmitters with maidenhead locators starting with DM, CM, DL, DN, EM and EN.

The launch I chose to look at was the SpaceX launch from the Vanderburg Space Force Base on the 06.11.2025 at 21:13 UTC.

The following graph shows the 20m band on the proceeding day of the launch (05.11.2025), the day of the launch (06.11.2025), and the following day (07.11.2025). 

​

The highlighted section on the 06/11/2025 after the launch (21:13) looks much more sparse when compared to the previous day, and the following day. That a change was observed, at roughly the time we expected it to occur, looked initially promising.

(I again reached the message limit so I will split this over yet another email).

[Isobel Smith - M5DUK]

However, according to the paper "First Observations of Large Scale Traveling Ionospheric Disturbances Using Automated Amateur Radio Receiving Networks" (https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2022GL097879 ), you should look at distances on the 20m band below 3000km to avoid transmissions with multi-hops. 

Therefore, when looking at the data for the 20m band again, with the distance reduced to below 3000km, you can see that the distances around 500km tend to increase on the 31.10.2025, compared to the day preceding and after it.

To make the data readable, the tx.loc was reduced to only include the maidenhead locators DM, CM, DL, DN.​

Thankyou once again for taking the time to look over the data, and please do let me know if you have any questions, 

Thanks,
Isobel de M5DUK

[Dr. Nathaniel A. Frissell Ph.D.]

Hi Isobel,

Have you read my 2022 Geophysical Research Letters paper? It is about identical large scale TIDs in WSPR/PSKReporter/RBN data.

I see that you are interested in TIDs related to a space shuttle launch. These are likely going to be small or medium scale TIDs, so I do not think my exact technique will work. In my paper, I plotted very large amounts of data together. Many of the smaller-scale features get washed out when you process the data the way that I did. Still, my paper may give you some ideas.

I think to see what you want, you would need to take a more finessed approach. I might look at individual pairs of stations that are transmitting across the region of interest and try to identify oscillatory behavior in some parameter. The WSPRDaemon group has specific stations that are keeping careful track of additional parameters that normal WSPR does not. These are likely useful here. Normally http://wsprdaemon.org/presentations.html is a good place to look for papers on this; it seems to be down right now. Gwyn Griffiths G3ZIL <gw...@autonomousanalytics.com>wrote most (all?) of them and will have good information.

Also note there is a tremendous amount of research on medium and smaller scale TIDs using GNSS Total Electron Content and SuperDARN. Just do a scholar.google.com search for this. My best SuperDARN MSTID work is available at https://doi.org/10.1002/2015JA022168.

Also, Grape Personal Space Weather Station Doppler data will likely be sensitive to this, also.

73 de Nathaniel W2NAF

From: ham...@googlegroups.com <ham...@googlegroups.com> on behalf of ghby...@k9trv.org <ghby...@k9trv.org>
Date: Tuesday, December 23, 2025 at 9:25 AM
To: ham...@googlegroups.com <ham...@googlegroups.com>
Subject: RE: [HamSCI] Help understanding how to look for evidence of TIDs in WSPR data

WARNING: This message originated from a source outside of the university.

To view this discussion visit https://groups.google.com/d/msgid/hamsci/015901dc7418%24036b6800%240a423800%24%40k9trv.org.

Please use your best judgment when opening attachments, clicking links, or replying to this email. If you suspect this is a phishing attempt, please forward to inf...@scranton.edu. Other questions can be directed to the Technology Support Center at (570) 941-4357 or techs...@scranton.edu.

[Gwyn Griffiths]

Hello Isobel

TIDs are certainly a fascinating subject and for your particular application I agree with Nathaniel that "a more finessed approach". A good starting would be a sketch showing what you can find out about a launch, you have got the launch site for starters, then find the direction of travel, as it might be important, when and how far 'down-range' does the rocket transit the E region at ~ 100 km high? 

A quick sketch for 6 November suggests to me the excellent Grape Personal Space Weather Station of W1EUJ which was at Oceanside, CA on 6 November. You can find its Doppler spectrograms at https://pswsnetwork.caps.ua.edu (you will need to 'register your station' if you have not used the site before), then navigate to the Observations tab and search for W1EUJ and start and stop of 5 and 7 November to get days either side. I'm looking at that data now, but I will let you draw your own conclusions about whether there were variations after 2113 UTC on 6 November above the background of WWV Doppler.

As for WSPR, Nathaniel mentioned how the enhanced data collection by WSPRDaemon users can be useful to study TIDs. It is well suited for 'a finessed approach' with just a single transmitter receiver pair. I've attached in a pdf an example of a type of medium scale TID observed in Doppler over the UK and with Total Electron Content anomaly maps to provide support as to what we were seeing.

Good luck with your studies.

Gwyn G3ZIL