Carl Luetzelschwab carlluetzelschwab at
Sun Dec 15 09:49:45 EST 2019

Hi to everyone,

>From ionization rates in the scientific literature, galactic cosmic rays
(GCRs) result in more electrons down low in the ionosphere (from
collisional ionization) - where ionospheric absorption occurs. So one would
think that the more cosmic rays, the more absorption - which is not good
for 160m (with absorption inversely proportional to the square of the
frequency, 80m is affected much less). Is there a direct one-to-one
relationship between GCRs and 160m propagation? I don't know because there
are other processes going on in the lower ionosphere that may also impact
160m. Trying to tie one single parameter to 160m propagation is not likely
the entire story.

As for the geomagnetic field (Ap) not being as low yet as in the last solar
minimum, the lowest Ap occurs right at solar minimum or just after - when
coronal holes (generally not CMEs) during the declining phase of the solar
cycle decrease.

So 160m continues to be a mystery - and I'm glad of it.

Carl K9LA

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