Friday, November 7, 2008

Sunspot Cycle 24 Kicks In

This just in from the NASA feed and it is important. We have been waiting for the next solar sunspot cycle to stick its head up for a long time and it just did. The long delay will still give sunspot fans plenty to play with for a while yet , but at least we are no longer speculating on why they are not to be found.

The problem we have with sunspot theory is that the era of the Little Ice Age is coincident with an apparent lack of sunspots. And the problem with that is that the observation of sunspots was then in its infancy and we are not sure just how accurate they in fact were. Out of that and a few hints from the Dalton minimum we have woven a skein of theory.

The fact remains that the forty year cycle does coincide with an observed forty year hurricane cycle and a forty year shift of heat into the Northern Hemisphere which has just been turned off a few months past and not with the eleven year cycles of the sunspots. The apparent driver that is big enough to shift heat back and forth is the Pacific Decadal Oscillation and it also just shut down.

The heat masses are large enough to qualify for the observed impact in the Arctic.

The short term evidence is now pointing to a full return of colder winters in the Northern Hemisphere. That means that I need to buy proper winter foot ware for the first time in twenty five years in Vancouver.

What this is doing, particularly if it all stands up over the next couple of years, is establishing a forty year cycle that peaks with the conditions experienced in 2007 and then switches back to cool for forty years or so.

Simply put we have a natural cycle that we can isolate from our long term data that appears to a simple atmospheric response not unlike El Nino and unlinked to sunspots and cosmic rays and CO2 speculation.

Its range is about one degree and does not explain the unusual events such as the Little Ice Age and the Medieval Maximum.

As I have posted earlier, the Little Ice Age fits the profile of a Alaskan Volcano that spewed huge amounts of gas and ash into the Arctic during an era that did not give us access to the right locales. I would guess that we had a string of volcanoes letting loose over a twenty year span which is completely believable for that locale. We are actually in a quiet era and it is still going bang every couple of years.

So what about the Medieval Maximum or for that matter the Roman Maximum? Both lasted for hundreds of years. My surmise is that this cool period is actually going to sit at or above the average for the past forty years. I still think that the long term trend is toward those higher temperatures and will only be interrupted by those volcanoes in Alaska.

The Sun Shows Signs of Life

10.07.2008

http://science.nasa.gov/headlines/y2008/07nov_signsoflife.htm?list1109684


Nov. 7, 2008: After two-plus years of few sunspots, even fewer solar flares, and a generally eerie calm, the sun is finally showing signs of life.

"I think solar minimum is behind us," says sunspot forecaster David Hathaway of the NASA Marshall Space Flight Center.

His statement is prompted by an October flurry of sunspots. "Last month we counted five sunspot groups," he says. That may not sound like much, but in a year with record-low numbers of sunspots and long stretches of utter spotlessness, five is significant. "This represents a real increase in solar activity."

Above: New-cycle sunspot group 1007 emerges on Halloween and marches across the face of the sun over a four-day period in early November 2008. Credit: the Solar and Heliospheric Observatory (SOHO).

Even more significant is the fact that four of the five sunspot groups belonged to Solar Cycle 24, the long-awaited next installment of the sun's 11-year solar cycle. "October was the first time we've seen sunspots from new Solar Cycle 24 outnumbering spots from old Solar Cycle 23. It's a good sign that the new cycle is taking off."

Old Solar Cycle 23 peaked in 2000 and has since decayed to low levels. Meanwhile, new Solar Cycle 24 has struggled to get started. 2008 is a year of overlap with both cycles weakly active at the same time. From January to September, the sun produced a total of 22 sunspot groups; 82% of them belonged to old Cycle 23. October added five more; but this time 80% belonged to Cycle 24. The tables have turned.

At first glance, old- and new-cycle sunspots look the same, but they are not. To tell the difference, solar physicists check two things: a sunspot's heliographic latitude and its magnetic polarity. (1) New-cycle sunspots always appear at high latitude, while old-cycle spots cluster around the sun's equator. (2) The magnetic polarity of new-cycle spots is reversed compared to old-cycle spots. Four of October's five sunspot groups satisfied these two criteria for membership in Solar Cycle 24.

The biggest of the new-cycle spots emerged at the end of the month on Halloween. Numbered 1007, or "double-oh seven" for short, the sunspot had two dark cores each wider than Earth connected by active magnetic filaments thousands of kilometers long. Amateur astronomer Alan Friedman took this picture from his backyard observatory in Buffalo, New York:

On Nov. 3rd and again on Nov. 4th, double-oh seven unleashed a series of B-class solar flares. Although B-flares are considered minor, the explosions made themselves felt on Earth. X-rays bathed the dayside of our planet and sent waves of ionization rippling through the atmosphere over Europe. Hams monitoring VLF radio beacons noticed strange "fades" and "surges" caused by the sudden ionospheric disturbances.

Hathaway tamps down the excitement: "We're still years away from solar maximum and, in the meantime, the sun is going to have some more quiet stretches." Even with its flurry of sunspots, the October sun was mostly blank, with zero sunspots on 20 of the month's 31 days.

But it's a start. Stay tuned for solar activity.

3 comments:

dreese said...

Interesting postulation on cause of the Little Ice Age. Any verification from glacial records? Would this not leave the cosmogenic isotopes in the dark?

arclein said...

This is going to be a subject for discussion for a long time. By putting up the various options, the researchers can look in the right places for data.

The problem of course is that alaska is banging away merrily for thousands of years and the only place that can give us a year by year resolution is the Greenland ice sheet.

I would love to look at a study that meticulously measures each years impact in the ice against the known volcanic signatures if that is possible at all.

The little ice age dominantly affected Europe and not too convincingly anywhere else. That does fit the Alaska model very well because the dust would always trend into the North.

Alternately, perhaps some mechanism locked the Pacific Decadal Oscillation in its southern most expression and perhaps also drained a lot of energy out of it. Except I do not think this has happened with the very big bangs we have had out of there and there were europeans in attendence at all times.

We end up coming back to Alaska as the one place that could do it and get away with it.

Unknown said...

There is a very close association between solar cycle length and temperatures. The Dalton and Maunder Minimums had very few sunspots and long solar cycles, which contributed to the cooling. Four of the five shortest solar cycles of record were in the latter half of the 20th century and thus caused the warming (with the exception of the 1970s, the coolest decade of the 20th century, and this solar cycle was longer.

However, the sun is now chaning back to a longer cycle, cycle 23 is not yet over and is now 12 years 6 months long, the longest cycle since 1795 and the start of the Dalton Minimum, a 40 year very cold period. There are many signs of cooling global temperatures throughout the earth, and this happens to coencide with a longer solar cycle, this helps to prove the connection. This year is likely to have the fewest sunspots in a Century and according to David Archibald, using historical data relating global temperatures in the past to solar cycle activity (not a theory or computer model but a historic record), global temperatures will fall 2.5 degrees celcius (this cooling has already started) and will last for at least 40 years.

Lots of similar information on my website, www.isthereglobalcooling.com