We seek to understand and document all radio transmissions, legal and otherwise, as part of the radio listening hobby. We do not encourage any radio operations contrary to regulations. Always consult with the appropriate authorities if you have questions concerning what is permissable in your locale.

Author Topic: Effects of fires and high altitude smoke on propagation?  (Read 304 times)

Offline Rizla

  • Full Member
  • ***
  • Posts: 179
  • Karma: +3/-0
  • Sonoran Desert, AZ
    • View Profile
Effects of fires and high altitude smoke on propagation?
« on: September 12, 2020, 2306 UTC »
I found this:

The Signal Propagation Effects on IEEE 802.15.4 Radio Link in Fire Environment
https://www.researchgate.net/publication/232708332_The_Signal_Propagation_Effects_on_IEEE_802154_Radio_Link_in_Fire_Environment

and a PhD thesis from Australia. I don't know if they've experimented on the kinds of high altitude smoke atmospherics over CA and the SW right now, which are turning the sun orange, blotting out the stars, and making the sun disappear behind grey before sunset.

The studies were 50 meters and up, for emergency comms. I didn't find much on HF effects.

Also found this map of current air quality:
https://www.purpleair.com/map?opt=1/mAQI/a10/cC0#8.6/32.3781/-111.1294

Which is pretty lousy here, but nothing compared to the West Coast right now.

Mucho thanks in advance for any resources on the subject(s).
QTH: Sonoran Desert, AZ. Kenwood TS-820S, FT-891, Tecsun 880, neophyte in a forest of antenna wire.

Offline ChrisSmolinski

  • Administrator
  • Marconi Class DXer
  • *****
  • Posts: 26091
  • Karma: +55/-45
  • Westminster, MD USA
    • View Profile
    • Black Cat Systems
Re: Effects of fires and high altitude smoke on propagation?
« Reply #1 on: September 12, 2020, 2315 UTC »
Interesting!
Chris Smolinski
Westminster, MD
eQSLs appreciated! csmolinski@blackcatsystems.com
netSDR / AFE822x / AirSpy HF+ / KiwiSDR / 900 ft Horz skyloop / 500 ft NE beverage / 250 ft V Beam / 58 ft T2FD / 120 ft T2FD / 300 ft south beverage / 43m, 20m, 10m  dipoles / Crossed Parallel Loop / Discone in a tree

Offline Rizla

  • Full Member
  • ***
  • Posts: 179
  • Karma: +3/-0
  • Sonoran Desert, AZ
    • View Profile
Re: Effects of fires and high altitude smoke on propagation?
« Reply #2 on: September 13, 2020, 0118 UTC »
The air pollution here is worse than last night, and the night before. We're a good distance from the forests burning on the West Coast.

Subjectively on HF, it seems that reception may be up a bit, and transmission dampened, so to speak. There were a lot of contests on today, and I heard a lot of people, but only made as far as Alabama on 100 watts tx/QSO-wise. At least four contacts in that state.  Now, whether that was due to lack of trying and/or the weird ash cloud hanging over parts of the southern/western US....? Dunno. I'll be talking on the radio tonight and hope to learn more about conditions out in CA.

[Edit: found typically curmudgeonly Eham discussion: https://www.eham.net/community/smf/index.php/topic,130877.0.html
AFAIK they were discussing the situation a few days ago. I wonder who has computer models for a situation like today? People who study
Volcanoes who are hams, maybe...?

Another Edit: It looks like a minor Mt. St Helens level out there tonight, and I am in Southern AZ...]
« Last Edit: September 13, 2020, 0150 UTC by Rizla »
QTH: Sonoran Desert, AZ. Kenwood TS-820S, FT-891, Tecsun 880, neophyte in a forest of antenna wire.

Offline ChrisSmolinski

  • Administrator
  • Marconi Class DXer
  • *****
  • Posts: 26091
  • Karma: +55/-45
  • Westminster, MD USA
    • View Profile
    • Black Cat Systems
Re: Effects of fires and high altitude smoke on propagation?
« Reply #3 on: September 13, 2020, 1141 UTC »
I understand the effects on the microwave bands, but given the smoke particle size I doubt there's any effects on HF. 
Chris Smolinski
Westminster, MD
eQSLs appreciated! csmolinski@blackcatsystems.com
netSDR / AFE822x / AirSpy HF+ / KiwiSDR / 900 ft Horz skyloop / 500 ft NE beverage / 250 ft V Beam / 58 ft T2FD / 120 ft T2FD / 300 ft south beverage / 43m, 20m, 10m  dipoles / Crossed Parallel Loop / Discone in a tree

Offline Rizla

  • Full Member
  • ***
  • Posts: 179
  • Karma: +3/-0
  • Sonoran Desert, AZ
    • View Profile
Re: Effects of fires and high altitude smoke on propagation?
« Reply #4 on: September 13, 2020, 1930 UTC »
So, you're saying that it might be my own incompetence and lack of killer antenna, rather than my proposal? How dare you? ;-)

I get it, I get it. I was on the local repeater last night, none of the guys there (none of them were HF guys, just repeater guys) wanted to talk about that the sky isn't blue these days.

My whole thing is that I don't think anyone's made a model for this stuff. I think HF/VHF/UHF is the least of our concerns and problems. That's a side issue to the real human damage going on.

My other thing is that it's only on a board like this one that I could even voice a concern. The straight laces of Ham Radio don't want to listen to pirates, how are they gonna care that the sky isn't blue?

By the way, I thought I'd said this before, but huge kudos to Chris S.... As you said, Chris, it's "interesting".... 

[Edit: there is no forum/board like this one, and no community like the one here, on Earth AFAIK. Chris S got the job done. Again, kudos and a million thank you's that are thought all the time but too rarely said...]

Some of us have firefighter friends....

Thanks for putting up with my rants, as always!
« Last Edit: September 13, 2020, 1935 UTC by Rizla »
QTH: Sonoran Desert, AZ. Kenwood TS-820S, FT-891, Tecsun 880, neophyte in a forest of antenna wire.

Offline EricPeterson

  • Newbie
  • *
  • Posts: 18
  • Karma: +0/-0
  • Warren county VA (Shenandoah Valley)
  • website in progress...
    • View Profile
    • Old engineer but new at this
    • Email
Re: Effects of fires and high altitude smoke on propagation?
« Reply #5 on: September 15, 2020, 1234 UTC »
From NWS State College:

Smoke can filter out shortwave radiation from the sun resulting in cooler days, but is not as effective in absorbing longwave radiation (the smoke particles are too small), so it has less impact on overnight low temps

I know solar shortwave and longwave heat from the earth is not RF but it's all radiation.

Offline BoomboxDX

  • Hero Member
  • *****
  • Posts: 699
  • Karma: +5/-0
    • View Profile
Re: Effects of fires and high altitude smoke on propagation?
« Reply #6 on: September 24, 2020, 0350 UTC »
To truly affect ionospheric propagation, the smoke would have to be 50-100 miles up, I think.
An AM radio Boombox DXer.
+ GE SRIII, PR-D5 & TRF on MW.
The usual Realistic culprits on SW (and a Panasonic).