I guess you are glad that you link to a pdf without figures, otherwise you would clearly see the nonsense that these guys claim from Figs. 3 and 5 and 6 for example. Oh, it can be in phase, or out of phase and an increase can happen if the Wolf number increases or decreases, and whatever.
For those interested in the real publication go here to ResearchGate (beware, looooong download time)
You're sounding a bit bitter tusenfem
Thanks for posting the link to ResearchGate it is important that sources can be easily checked and I usually rush too much

So tusenfem WHY can't the Sun outputs that are Earth facing / impacting (such as: coronal holes, flares, filaments, sudden changes in the solar wind speed, changes in polarity ... etc) may "trigger" earthquakes, volcanoes and major weather events be ELECTROMAGNETIC in nature ?
Now don't go on about magnetic reconnection !
You know Hannes Alfvén warns against magnetic reconnection in this ...
On frozen-in field lines and field-line reconnection
Abstract
It is shown that ‘frozen-in magnetic field lines’ and ‘magnetic field-line reconnection’ are unnecessary and often misleading concepts.
Remember tusenfem
Magnetism and electricity are not separate phenomena
they are the related manifestations of an underlying electromagnetic force.
and
Electromagnetism:
in a key development for modern physics, electricity and magnetism were `unified' into electromagnetism
the connection develops from the fact that an electric current (the flow of electrons in a metal) produces a magnetic field
Faraday shows that a changing electric field produces a magnetic field and, vice-versus, a changing magnetic field produces an electric current
Maxwell completes the theory with a full mathematical description of the relationship between electric and magnetic fields = electromagnetism
!