"E layer ionization ( not sporadic-E -- that's completely different) hasn't
> yet begun to increase significantly. As we get closer to solar maximum
> consistently higher E-layer MUFs will blanket 40 meter DX openings
> until later in the afternoon"
Could someone explain this one further? Does the higher E layer MUF keep
signals from reaching the F layer for 40 meter DX? Or does it cause
shorter skip openings on 40 meters which covers up the DX stations, or what
is the connection?
73 John AF5CC
On Thu, Nov 26, 2020 at 1:46 PM K9MA <k9ma@sdellington.us> wrote:
> Thanks, Frank, for the excellent explanation.
>
> 73,
> Scott K9MA
>
> On 11/26/2020 1:19 AM, donovanf@erols.com wrote:
> >
> >
> > Sunspot activity has increased dramatically over the last two months.
> > Most days this month have had multiple and more active sunspots
> > resulting in the solar flux index exceeding 100 for the first time since
> > September 2017. SFI is likely to remain above 100 during the CQWW
> > CW DX Contest and remain at 90 or above for at least another week.
> >
> >
> > But recall that both the sunspot number and the 2800 MHz solar flux
> > index are proxies for the the actual source of F layer ionization that
> cannot
> > be observed on the surface of the Earth: extreme ultraviolet radiation
> >
> >
> > We can't yet determine if this is a short term surge or a sustained
> > increase in sunspot activity. We'll have a better understanding in about
> > six months.
> >
> >
> > The first year of increased sunspot activity is a sweet spot in the
> solar cycle because:
> >
> >
> > - increased extreme ultraviolet radiation starts to open the 10 meter
> band,
> > makes 15 meters more reliable including more frequent JA and long path
> openings
> > keeps 20 meters open later into the night and opens it well before
> sunrise
> > keeps the MUF into Europe above 7 MHz during most or all of the night
> >
> >
> > - coronal hole high speed streams that cause elevated K indices during
> > the declining years of the solar cycle and during solar minimum are
> > now less frequent and not as strong, keeping the K index consistently
> > low for about the next year.
> >
> >
> > - fast coronal mass ejections (fast CMEs) that cause much more severe
> > and more frequent geomagnetic disturbances won't start to occur
> > regularly until at least late next year.
> >
> >
> > - daytime D layer absorption that affects 160 and 80 meters much more
> > severely than 40 meters hasn't yet begun to increase significantly as
> > it will when we get closer to solar maximum
> >
> >
> > - E layer ionization ( not sporadic-E -- that's completely different)
> hasn't
> > yet begun to increase significantly. As we get closer to solar maximum
> > consistently higher E-layer MUFs will blanket 40 meter DX openings
> > until later in the afternoon.
> >
> >
> > Enjoy the ride especially this weekend in the CQWW CW DX Contest
> >
> >
> > 73
> > Frank
> > W3LPL
> >
> >
> >
> > ----- Original Message -----
> >
> > From: "Alfred Laun" <hs0zar@gmail.com>
> > To: "PVRC" <pvrc@mailman.qth.net>
> > Sent: Thursday, November 26, 2020 4:09:22 AM
> > Subject: [PVRC] Solar Cycle Rise
> >
> >
> >
> > We are seeing the Solar Flux Index hit a daily peak of 104 already, even
> though solar minimum is said to have been reached only 11 months ago in
> December 2019. I thought this seems faster than it rose last time, so I
> went to
> >
> > https://www.swpc.noaa.gov/products/solar-cycle-progression
> >
> >
> >
> > to take a look at what happened just after the last minimum. According
> to that chart, monthly average solar flux bottomed out at 65.7 in July of
> 2008. Monthly average solar flux did not get to over 100 until March of
> 2011, or 32 months later.
> >
> >
> >
> > Granted, the last solar minimum began with an SFI about 2 points lower
> than this latest minimum, but still, it looks to me like the rise is faster
> this cycle.
> >
> >
> > Yes, there are complications, like the difference between actual daily
> values and the smoothed daily values which are used to produce a visual
> curve that doesn't jump all over the place. And what we have today are
> daily values, not monthly values. But it still looks to me like things are
> moving along pretty fast.
> >
> >
> > I am not a scientist, so I invite all of those interested to go to that
> site, hover your mouse over the curve, and see what you come up with.
> >
> >
> > 73, Fred, K3ZO
> >
> > ______________________________________________________________
> > PVRC mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/pvrc
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:PVRC@mailman.qth.net
> > Message delivered to donovanf@starpower.net
> >
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> > Please help support this email list: http://www.qsl.net/donate.html
> >
> > _______________________________________________
> > CQ-Contest mailing list
> > CQ-Contest@contesting.com
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>
>
> --
> Scott K9MA
>
> k9ma@sdellington.us
>
> _______________________________________________
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>
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