Thursday, August 27, 2009

Solar activity and climate change

From the 31 August 2009 Greater Niagara Newspapers

SOLAR ACTIVITY AND CLIMATE CHANGE
By Bob Confer


If you participated in the CB radio craze of the 1970s and 1980s you’ll remember that quite often communication become difficult if not impossible. There were numerous times when the skip (signals from afar) would roll in and CB operators from all over the US (and world, for that matter) would drown out your conversation with someone in the next town over. Nowadays, it’s a very rare day when you’ll be able to hear anyone beyond the line of sight.

If you’re a stargazer or someone who just likes to step outside at night for a breath of fresh air or a smoke, you’ll remember seeing plenty of aurora in years past, with some pretty impressive displays of the northern lights in the late-80’s and early-90’s. You may have noticed that those displays have been almost nonexistent in recent years. Those gaudy shows still occur in the polar region, but we here in the mid-latitudes have not been so fortunate.

These two declines in activity – one on the airwaves, the other in the air – are directly related to one another and tell us something about the state of the sun. Solar activity, which can typically be tracked in an 11-year pattern of highs and lows, determines a number of things which include the amount of solar radiation and space weather of all types (flares, ejections, etc.) that reach the Earth. The cycle’s peak and therefore the sun’s overall activity is made evident by sunspots, dark spots of magnetic activity on the sun’s surface.

We are currently amidst a deep low in the solar cycle, accounting for the decrease in skip and aurora, and a total lack of sunspots. According to spaceweather.com, the sun is setting modern-day records for inactivity, with the current stretch of days without a sunspot at 47 and 700 days of no spots whatsoever since 2004. This period, known as the solar minimum, is far longer than most. The average length of a minimum is 485 days.

This minimum looks like it will go on for a very long time based on a July study issued by William Livingston and Matt Penn of the National Solar Observatory. They showed that the magnetic field strength of sunspots has been weakening at a fast-paced linear rate (one that they have verified since a similar study 5 years earlier), which may mean that sunspots will be nonexistent by 2015, putting the sun into a historic low similar to the Maunder Minimum of 1645 to 1715 when the sun’s face was basically free of blemishes.

So what does this mean to the average person who’s not a radio enthusiast or amateur astronomer? It could mean a great deal and it just might disprove the global warming alarmists. If this is a repeat of the Maunder event the world will plunge into a prolonged period of cold. The Maunder Minimum happened during the coldest part of the Little Ice Age and many scientists don’t see this as a coincidental occurrence. They believe that the lack of solar activity caused the decline in global temperatures which, based on careful study, showed the Earth cooled by more than 3 degrees Fahrenheit during the minimum. This effect was considerably-more pronounced in North America and Europe where the winters became longer and more frigid, native Americans formed collectives to beat the associated food shortages, glaciers advanced, and Iceland became sealed off by ice in 1695.

To put this cooling into perspective, the Earth has warmed by just under 1 degree Fahrenheit since 1901. Some cite the warming trend as the direct result of Mankind’s assault on the atmosphere with greenhouse gas emissions. Yet, studies show that across the twentieth century’s multiple solar cycles the magnetic energy leaving the sun more than doubled while ultraviolet radiation grew by 15 percent. This is the exact opposite of what happened during the Maunder Minimum: In the 1900s we had an overactive sun which in turn led to warmer Earth.

It was not an overactive population, as some would say, that caused global warming. It’s foolish – even vain – to believe that Man is powerful enough to change the temperature of our planet. But, the sun, on the other hand, the very glue that keeps our solar system together and gives us the light and heat so crucial to life, is more than powerful enough to change temperatures when it’s in one of its moods. And it’s just getting into one of those moods, a very tranquil one at that. That cool demeanor will create a cool Earth and, once that happens, you can bet we’ll all be begging for global warming.

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