EFFECT OF HIGH SOLAR ACTIVITY ON GLOBAL WEATHER PATTERNS

[RNS]

A part of this is taken from a discussion in our official winter 2003/04 outlook. The complete S2k version of that will be posted tomorrow evening (as i did not want to post today out of respect for Keith Allen/s visit).

As Many of you know, high Solar activity has a very significnat impact on global weather patterns.

The sun goes through 11 year solar cycles, which are characterized by changes in sunspot numbers. The 11 year cycle begins with low solar activity the first one to three years then noticeable increases in activity are noted between years four and six, with a decrease thereafter. The solar maximum defines the period of the solar cycle in which sunspot numbers are the highest of the 11 year period. While there is only one period in which solar activity and sunspot numbers are maximized, one can have as many as two high activity peaks. Our current solar cycle (SS#23) was noted for having two apparent peaks, the first of which occurred in the winter of 1999/00 and the second in 2001/02.

Solar cycle 21 displayed one clear peak in December of 1979, with a steady decrease in soar activity thereafter. Solar cycle 22 featured a similar though less prevalent peak, in 1991, after the primary peak in 1989. Solar cycle 23, proved to be weaker than solar cycle 22, though featured a much more prevalent secondary peak in early 2002 following the primary peak in 2000.

http://www.dxlc.com/solar/solcycle.html

The term 10.7cm radio flux describes the measure of solar radio emissions at a wavelength of 10.7 centimeters which are released from hot gasses trapped within the magnetic loops.

High geomagnetic activity which occurs during the solar maximum has significant to severe impacts on our normalized weather patterns here on earth during all seasons, however most notably, these effects are felt the most in the late fall, winter, and early spring.

The following features are most significantly affected by high geomagnetic activity:

Changes in the strength of the Aleutian and Icelandic low pressure centers:

Significant geomagnetic activity can cause the weakening of the Aleutian low, while allow for the strengthening of the Icelandic low, resulting in a dominating RNA (trough in the west ridge in the east) or fast west to east (zonal) flow across the northern hemisphere. Recall the weakening of the Aleutian low and strengthening of the Icelandic low results in appositive EPO and Positive NAO which leads to a predominantly negative PNA (RNA) pattern during winter.

Less Cloud cover (Svensmark Effect):

During periods when solar activity is very high, the earth’s natural protective magnetic field is the strongest, which tends to block cosmic ray neutrons from entering the atmosphere. Long-term observations have shown that during periods of high geomagnetic activity, these neutrons are significantly less than what they would normally be near to solar minimum. These neutrons have an ionizing effect that aids in the production of clouds (an effect which is increased greatly, especially when there are higher levels of volcanic ash and aerosols present in the atmosphere). The reduction of cloud neutrons during the solar maximum has been shown to have a diminishing effect on the amount of cloudiness globally, leading to less precipitation, drought, and possibly warmer surface temperatures due to the decreased soil moisture, and increased surface heating due to the direct effect of the decrease in cloudiness its self

Large-Scale Effects on the Low and Mid-latitudes:

High solar flux activity (increased 10.7cm radio flux, luminosity, solar irradiance and UV), produce a chemically based reaction on ozone which leads to increased temperatures in the mid and lower latitudes. This warming eventually feeds-back to thermal ridging and above normal heights, even in spite of factors here on earth arguing for different effects. It is at these latitudes where the effect of the forcing from the increased flux is the strongest.

The High geomagnetic activity cycle is often offset from the sunspot and flux cycle, thus the effects of increased solar activity overall, can have the greatest effects in different locations. High sunspot numbers and flux tend to have the greatest effects in the lower and mid-latitudes, while the high geomagnetic activity cycle has the greatest effects on the Polar Regions. High geomagnetic, and flux activity occurring at the same time can result in the warmest possible weather patterns here on earth during the winter season. This is because larger coronial mass ejections or CME’s associated with increased geomagnetic activity, (produced by dying flares/sunspots and Coronial holes) are favored a this stage of the solar cycle.

Large-Scale Effects on the High latitudes:

High geomagnetic activity effects the high-latitudes the greatest due to the fact that the geomagnetic waves and charged particles are drawn to the earth’s magnetic poles, thus the effects are felt the strongest in the polar regions. This activity, as previously eluted to can lead to the strengthening of the Icelandic low and weakening of the Aleutian low.

[Stormsfury]

From Spaceweather.com (and speaking of solar activity)

SOLAR OUTLOOK: Giant sunspots 486 and 488, which caused so much intense space weather last month, have been transiting the farside of the sun since Nov. 4th. Now they're back. The pair are emerging over the sun's eastern limb where they can once again direct explosions toward Earth. Meanwhile, sunspot 484 near the middle of the solar disk has developed a complex magnetic field that harbors energy for X-class solar flares.

Strong solar activity is possible in the days ahead.

AURORA WATCH: A coronal mass ejection (CME) is heading toward Earth; it was hurled into space by an M-class explosion near sunspot 484 on Nov. 18th (0800 UT). Sky watchers at all latitudes should be alert for auroras when the CME arrives after nightfall on Nov. 19th or 20th.

[RNS]

I know...which concerns me regarding our pattern change.

10.7cm radio flux is back up to around 1500, and on the increase. I dont think that we will se the type of activity that we say last time around from those regions.

http://www.dxlc.com/solar/

[Stormsfury]

I know...which concerns me regarding our pattern change.

10.7cm radio flux is back up to around 1500, and on the increase. I dont think that we will se the type of activity that we say last time around from those regions.

http://www.dxlc.com/solar/

I figured you knew, RNS. 488 looks very impressive and 486 is just coming into view ... I seriously doubt that we'll see the historical CME that was launched from 486 as the sunspot exited Earth's View a few short weeks ago ... (I didn't realize just how fast the sun's day was - something like 27 Earth days) ...

But it's interesting that Spaceweather.com is reporting a potential for auroras that might be seen in all latitudes yet again, and the potential for an X-class flare (and subsequent CME) from 484 ... I will be watching with interest with 486, and 488 as well ...

SF

[RNS]

as long as the sunspots in those regions weaken, we have no reason for concern (as they should) if new sunspots should appear in othe regions...tehn we have reason for significnat concern regarding a third solar max.

as far as i know, there were no third peaks within the 11 year cycles. So if this should prove to be one, it would be historic.

also the sun goers through corresponsing centruy long and millennial cycles, however, little is known about those two aspects of the sun.

[wxid]

Auroura fx can't be seen from Maryland-Va can they? I'm pretty sure they can't , but didn't know if this was a diff situation? If so, might need to drag the ol' Pentax 35mm out!

[NEwxgirl]

wxid,

it depends on the strength of the flare. stronger X class flares will produce better arouras. neither sunspots 486 or 488 will produce as strong of flares as what we saw the last two weeks of october.

[NEwxgirl]

StormsFury, i like your avatar thats a really cool pic of arouras!

[JCT777]

RNS and SF - great posts (as always). It would be cool if auroras could be viewed again, but also I would hate to see high solar activity have any kind of negative effect on cold air/snow.

[Stormsfury]

RNS and SF - great posts (as always). It would be cool if auroras could be viewed again, but also I would hate to see high solar activity have any kind of negative effect on cold air/snow.

Thanks, John.

StormsFury, i like your avatar thats a really cool pic of arouras!

Thanks, NEWxGirl and welcome to Storm2k! I found that aurora pic on Spaceweather.com and have been fascinated with auroras ever since I got two nights of viewing them in CHS. Oh, let's not forget tonight!! (part of the reason I've not been around) ...

SF

[WXBUFFJIM]

It's been wonderful to witness the kind of spaceweather as we have witnessed over the last few weeks. Auroras this far south is not real common. It was gorgeous to see back in late October. The auroras were directly overhead and we're talking about beautiful red auroras too!!!

Jim