No one can tell if the old cycle has ended until the new cycle has built up some steam over about a six month period. Well, the above Sunspot Prayer Rug may provide new evidence they may be able to declare SC#24 actually started last December or January.
DESCRIPTION OF FIGURE
The vertical axis is latitudes on the Sun, with the Sun's equator at the middle. The horizontal axis is years, from mid-1994 to the present. The red-yellow bands represent solar jet streams, thousands of miles below the surface of the Sun.
The vertical blue line at the left indicates when SC#22 ended and SC#23 started. Note that the start of a solar cycle is marked by a jet stream that initiates at about 45º North and South latitudes and spreads up and down as the years go by. SC#23 began in 1997 when the jet stream from SC#22 got down to what they call the "critical latitude" of 22º. NASA is excited that the jet stream from SC#23 is now down to about that critical latitude! That, they say, could (finally) mark the start of (long-awaited) SC#24.
Well, they could be correct - or not. The black contours on the Sunspot Prayer Rug represent sunspot activity. Note that the black contours representing SC#22 end in 1997. Nearly simultaneously, new black contours representing SC#23 sunspots begin in the mid-latitudes.
A possible problem with the NASA interpretation is that the SC#23 sunspots end in mid-2008, but the SC#24 sunspots have not cranked up yet, a year later. This is very different from the transition between SC#22 and SC#24 when the new cycle started in earnest immediately after the old cycle ended. Why is this transition so different from the previous one? Could the year-long sunspot pause indicate a more fundamental change in the Sun's internal, natural cycle behavior? Perhaps the idea that a new cycle will begin when the jet stream gets to 22º latitude does not apply in the current and very different situation?
HOW YOU CAN HELP NASA
A few weeks ago, I added a new feature to this Blog where you can watch the day-to-day development of the next sunspot cycle. Have a look in the right-hand column, just below the Dilbert comic for a NASA-supplied image of the Sun. That image will change daily and allow you to help NASA look for sunspots.
WHY DO YOU CARE ABOUT SUNSPOTS?
As described in a previous posting on this Blog, there is an historical connection between periods of low sunspot activity and cooling trends. If the start of SC#24 is further delayed, it is likely it will peak later and at a lower level than originally expected. If we are lucky enough to get a series of weak sunspot cycles, that may provide decades of cooling that may counteract the estimated 0.5ºC actual warming our Earth has experienced over the past 150 years.
Although CO2 levels continue to increase at a rapid pace, it appears the Global Warming trend has abated, or perhaps reversed a bit, over the past ten years. A bit of Global Cooling will give us breathing room to correct our excessive release of previously-sequestered carbon (coal, oil, gas) into the atmosphere. Right now, the politicos are hell-bent on imposing the Cap & Trade Scam that will further destroy our economy and not reduce Global Warming very much. Let's hope they will reject that approach and work on something more conservative that will actually work, such as the Revenue-Neutral Carbon Tax .