How does Solar activity affect British winters?

[SqueakheartLW]

I did see some comments here recently about solar activity and solar cycles and how they affect the chances of the UK getting a milder or colder winter so decided to go into a bit of research of my own to see if there is some sort of link between the stage in a solar cycle, whether it is an odd or even cycle and the CET anomalies for the months from December through to March.

The winters covered are those from 1755/56, the first one covered fully by the start of solar cycle 1 right up to 2020/21, the last complete winter CET data we have and this is what the result came up as.

 

Now some obvious things stick out here already, Colder winters are more likely around or just after solar minimum but it depends on whether it is a transition from an odd to even cycle or even to odd. It seems odd to even has a much greater chance of coming out colder than average compared with even to odd which rather strangely comes out as a milder than average signal.

It also seems our best chance of a cold winter was last year in 2020/21 as that matched up to the colder signal for early odd ascending whilst this winter is most likely to fit into the mid or possibly late odd ascending and both of those appear to have a milder signal.

Another strange signal is how solar maximum in even cycles have a colder than average signal too. This came as a surprise to me as I would have expected solar maximum to go with mild all the time as a base signal. Another curious thing is that solar maximum seems to have a strong signal for a cold December too.

There also seems to be an overall tendency for colder winters to appear after solar maximum in odd cycles with increasing frequency, peaking around solar minimum odd to even when the signal starts to reduce and disappears once solar maximum even has occurred.

Conclusions

Colder winters are more likely when Descending down from Solar maximum in an odd cycle, peaking at the odd to even minimum transition before the signal reduces somewhat after solar maximum in the next even cycle.

Milder winters are more likely in Descending down from Solar maximum in an even cycle with solar minimum even to odd favouring mild. The ascending even phase is associated with milder winters too but there is a signal for at least a chance of a colder winter just after the even to odd minimum in the earliest stage of the ascending odd cycle.

Just thought I'd share this one with you as well.

It appears at first glance that ascending solar cycle phases seem to correspond with front loaded winter signals whilst descending solar cycle phases seem to favour more of a back loaded winter.

It is also apparent how ascending even cycles are in general colder than their corresponding odd ascending cycles.

It is also clear to see the general milder signal overall between Early Even Descending phase and Early to Mid Odd Descending before the general switch to the colder signal from before solar minimum odd to even phase through to Solar maximum of even cycles.

Basically the next best chance of us seeing colder than average winters is unlikely to happen before the mid point of the 2020's at least and our best chances will come around 2028/29 to 2032/33 to get our next possible string of colder winters as this is the very likely period of late odd descending to ascending even solar cycle phase.

There are winters in all sections that go against this so that doesn't mean we won't get a colder winter before this time. It's just the dice are more loaded in favour of colder winters in the period 2028/29 to 2032/33.

[jonboy]

14 hours ago, SqueakheartLW said:

I did see some comments here recently about solar activity and solar cycles and how they affect the chances of the UK getting a milder or colder winter so decided to go into a bit of research of my own to see if there is some sort of link between the stage in a solar cycle, whether it is an odd or even cycle and the CET anomalies for the months from December through to March.

The winters covered are those from 1755/56, the first one covered fully by the start of solar cycle 1 right up to 2020/21, the last complete winter CET data we have and this is what the result came up as.

 

Now some obvious things stick out here already, Colder winters are more likely around or just after solar minimum but it depends on whether it is a transition from an odd to even cycle or even to odd. It seems odd to even has a much greater chance of coming out colder than average compared with even to odd which rather strangely comes out as a milder than average signal.

It also seems our best chance of a cold winter was last year in 2020/21 as that matched up to the colder signal for early odd ascending whilst this winter is most likely to fit into the mid or possibly late odd ascending and both of those appear to have a milder signal.

Another strange signal is how solar maximum in even cycles have a colder than average signal too. This came as a surprise to me as I would have expected solar maximum to go with mild all the time as a base signal. Another curious thing is that solar maximum seems to have a strong signal for a cold December too.

There also seems to be an overall tendency for colder winters to appear after solar maximum in odd cycles with increasing frequency, peaking around solar minimum odd to even when the signal starts to reduce and disappears once solar maximum even has occurred.

Conclusions

Colder winters are more likely when Descending down from Solar maximum in an odd cycle, peaking at the odd to even minimum transition before the signal reduces somewhat after solar maximum in the next even cycle.

Milder winters are more likely in Descending down from Solar maximum in an even cycle with solar minimum even to odd favouring mild. The ascending even phase is associated with milder winters too but there is a signal for at least a chance of a colder winter just after the even to odd minimum in the earliest stage of the ascending odd cycle.

Just thought I'd share this one with you as well.

It appears at first glance that ascending solar cycle phases seem to correspond with front loaded winter signals whilst descending solar cycle phases seem to favour more of a back loaded winter.

It is also apparent how ascending even cycles are in general colder than their corresponding odd ascending cycles.

It is also clear to see the general milder signal overall between Early Even Descending phase and Early to Mid Odd Descending before the general switch to the colder signal from before solar minimum odd to even phase through to Solar maximum of even cycles.

Basically the next best chance of us seeing colder than average winters is unlikely to happen before the mid point of the 2020's at least and our best chances will come around 2028/29 to 2032/33 to get our next possible string of colder winters as this is the very likely period of late odd descending to ascending even solar cycle phase.

There are winters in all sections that go against this so that doesn't mean we won't get a colder winter before this time. It's just the dice are more loaded in favour of colder winters in the period 2028/29 to 2032/33.

Thanks SqueakheartLW really interesting bit off work. One of the factors for me is the actual intensity of the cycle in that we are more likely to get colder episodes during weak cycles and more so if we have the second weak cycle and much less likely to have cold episodes when we have very active cycles. In your analysis I'm not sure whether you factored in cycle intensity?

[Methuselah]

By sheer coincidence, YouTube just linked me to this lecture on our human propensity to see patterns everywhere:

I may be a sceptic, but Solar Cycles have always fascinated me. Thanks for the good work @SqueakheartLW!

[SqueakheartLW]

12 minutes ago, jonboy said:

Thanks SqueakheartLW really interesting bit off work. One of the factors for me is the actual intensity of the cycle in that we are more likely to get colder episodes during weak cycles and more so if we have the second weak cycle and much less likely to have cold episodes when we have very active cycles. In your analysis I'm not sure whether you factored in cycle intensity?

Just stage in cycle and if it was odd or even. Maybe should see whether weaker maximum and deeper minimum makes a difference

[BLAST FROM THE PAST]

Nice work Squeaky, I posted in moans and groans thread that coming from even to odd or vice versa may make a difference to

our shores, and was looking into it.  I was coming to same conclusion, great post and thanks for getting it out there earlier
 

BFTP

Edited January 10, 2022 by BLAST FROM THE PAST

[jonboy]

I attach 2 documents (hopefully!!) One showing the cosmic ray count and what strikes me at present is how high that has remained over the last few years where in the past once minimum has past you see a sharp fall away, and secondly a link to a paper on the thermosphere climate index which shows the ebb and flow of how our thermosphere changes in temperature during solar cycles. Hope these add something to the mix

 

The Chill of Solar Minimum | Spaceweather.com (spaceweatherarchive.com)

 

The Chill of Solar Minimum | Spaceweather.com (spaceweatherarchive.com)

[blizzard81]

Many thanks Squeakheart for putting all this together . I really appreciate it and all the hard work you have put into this just like you do in the other threads. This analysis in such an important topic was well overdue. It just needed someone like yourself who has the ability, intelligence and dedication to do it. Many thanks again.