Propagation Trends 2013-2014

Dayton 2013 1

Solar Maximum !A Double Peaked Sunspot Cycle ?

Every 6 Meter DXer Remembers This! The Second Sunspot Peak of Solar Cycle 23

Dayton 2013

400 Years of Sunspot Observations60 years of high sunspot cycleshave probably come to an end

Dayton 2013

70 years

40 years

Solar Cycle 24compared to all solar cycles since 1944

Dayton 2013

Cycle 24

the lowest solar minimum in 100 yearsfollowed by the lowest solar cycle in 100 Years

Sunspot Cycle 24 ProgressActual vs. Prediction

http://solarscience.msfc.nasa.gov/images/ssn_predict_l.gif

5

Prediction

Su

nsp

ot N

um

be

r

Actual

Solar Cycle 24 Prediction compared to similar Solar Cycle 14

Dayton 2013

two years between Solar Cycle 14 peaks

many solar scientists expect a double peaked

Solar Cycle 24

Why are there Often

Double Sunspot Cycle Peaks?

Dayton 2013

solar northern and southern hemisphere sunspot cycle peaks never occur at the same time

Su

nsp

ot N

um

be

r

Solar Cycle 24 is similar to Cycle 14the solar southern hemisphere sunspot peak occurred two years after the northern hemisphere sunspot peak

Dayton 2013

two years between sunspot peaks

N S

southern hemisphere sunspots started to increase one year after the northern hemisphere sunspot

peak

Su

nsp

ot G

rou

ps p

er

Mo

nth

The Last Two Solar Cycles also had Double Peaksbut very different than weaker Solar Cycle 24

Dayton 2013

two years between sunspot peaks two years between

sunspot peaks

NN

SS

southern hemisphere sunspots started to increase one year after the northern hemisphere sunspot

peak

Sunspot Production has Slowed in Both Solar Hemispheres

Dayton 2013

northern hemispheresunspot production

slowed after peaking in Sep - Dec

2011

southern hemispheresunspot production

slowed after peaking in Jun - Jul 2012

SN

Su

nsp

ot G

rou

ps p

er

Mo

nth

southern hemisphere sunspot production continues tolag behind northern hemisphere sunspot production

?

Solar North-South Polar Field Reversalsolar maximum usually occurs when

both polar fields have reversed polarity

Dayton 2013

2012 2013

north polefield reversal in June 2012(smoothed)

south pole field strength is very slowly decreasingDec 2012 – Mar 2013

field reversal

north pole field strengthcontinues to slowly

increaseJuly 2012 – Mar 2013

Jan Jan

smo

oth

ed

pol

ar

field

str

eng

thm

icro

-Te

sla

the south polar field is progressing very slowly toward field

reversal

S

N

Weak Solar Cycle 24 has been Unusually Favorable for 160 and 80 Meters

The A-index has been much lower than normal

Dayton 2013

two years between Solar Cycle 23 peaks

the A index usually increases during the first two years

after solar maximum

The A-Index may increase moderately after Solar Cycle 24 maximum

unusually low A index

A Long Range Estimate of Solar Cycle 25are sunspots disappearing?

http://myweb.wwu.edu/dbunny/pdfs/Solar-Cycle-25-Amplitude-estimate.pdf

some solar scientists expect Cycle 25 to be the weakest solar cycle in 400 years

http://www.landscheidt.info/?q=node/280