Solar Cycle 23 and Early Predictions for Solar Cycle 24

1
Solar Cycle 23 and Early Predictions for Solar
Cycle 24

• Carl Luetzelschwab K9LA

2
Cycle 23

• Maximum smoothed sunspot number of 121 in early
  2000

• Secondary peak in late 2001
• Great 6m F2 DX!

we are here
solar minimum

• Minimum expected in late 2006 / early 2007

• Were about a year and a half from solar minimum

3
The High Bands 10m, 12m, 15m

• At solar minimum, F2 openings on 15m to NA and EU
  will be of short duration

• If 15m is open, check 12m

winter month

• At solar minimum, no openings on 10m predicted to
  NA and EU

winter month
data from ARRL Antenna Book CD
4
17m A Good Place for a Band
predictions for JA to indicated area (December
around solar minimum) G 0700-0800 UTC (low
probability) I 0600-0830 UTC W2 no
opening WØ 2130-2200 UTC (low probability) W6 2130
-0030 UTC PY 2200-0700 UTC LU 2030-0900
UTC HZ 0300-0900 UTC VK4 2130-1530
UTC CN 0730-0800 UTC (low probability) ZS6 2230-10
30 UTC

• Prior to the WARC band allocations, 20m was the
  workhorse band for long haul DXing around solar
  minimum

• 17m has the long haul characteristics of 15m, but
  the MUF need not be as high

• Get on 17m!

Working Peter I on 17m 3Y0X Feb 2006
2100-0930 UTC
data from W6ELProp
5
80m and 160m

• Geomagnetic field activity is quietest at and a
  couple years after solar minimum

quietest
quietest

• Most severe impact is to paths that go to high
  latitudes (those through and near the auroral
  oval)
• JA to WØ
• JA to W1, W2, W3

data from K9LA
6
30m and 40m

• Propagation on 160m and 80m is dependent on
  absorption

• Propagation on 20m, 17m, 15m, 12m, and 10m is
  dependent on MUF (maximum usable frequency)

• 30m and 40m are transition bands not as
  dependent on absorption and not as dependent on
  MUF
• Of all the bands, they probably change the least
  over a solar cycle

7
Things To Do At Solar Minimum

• Watch for north-south paths on the higher bands

• Monitor the Sun for unusual sunspot activity that
  could help the higher bands
• www.dxlc.com/solar, sec.noaa.gov,
  spaceweather.com, etc

• Participate in contests
• www.ncjweb.com/contestcal.php

• Get on the low bands

8
All Recorded Solar Cycles

• Data is cyclic in nature

our lifetime

• Weve lived through the highest recorded solar
  cycles

• It sure looks like were headed for an extended
  period of low solar cycles

9
Cycle 24 Prediction

• As Cycle 23 winds down, were seeing more and
  more predictions from the scientific community

• Most predict that Cycle 24 will be no greater
  than Cycle 23

• Some are even predicting a maximum smoothed
  sunspot number of around 75
• Havent seen anything that low since Cycle 16
  (1923 1933)

from Schatten
10
Summary

• About a year and a half from solar minimum

• Stay active on the higher bands
• Watch for sporadic E and north-south F2
  propagation
• Monitor solar activity for unusual sunspot
  activity
• Participate in contests

• Get your low band station ready
• 2006, 2007, and 2008 should be good years