Tuesday, September 02, 2008

The global cooling debate.

Daily Tech: Sun Makes History: First Spotless Month in a Century.


The event is significant as many climatologists now believe solar magnetic activity – which determines the number of sunspots -- is an influencing factor for climate on earth.

Delta Farm Press: Global cooling gains momentum among scientists.


“Carbon dioxide is not to blame for global climate change, Sorokhtin said. “Solar activity is many times more powerful than the energy produced by the whole of humankind. Man’s influence on nature is a drop in the ocean.”

Canadian climatologist Timothy Ball said, “If we are facing (a crisis) at all, I think it is that we are preparing for warming when it is looking like we are cooling. We are preparing for the wrong thing.”

wattsupwiththat: Livingston and Penn paper: “Sunspots may vanish by 2015″.

Belfast Telegraph: Is there a cold future just lying in wait for us?

On-Line Opinion: Activity is quiet on the sunspot front.


At the time of writing the sun is still spot free. NASA solar physicist David Hathaway points out, quite rightly, that the sun’s behaviour is within major statistical limits - just. The average solar cycle lasts 131 months plus or minus 14 months and the current cycle - the quiet period counts as part of the old cycle - has lasted nearly 143 months. The solar cycle went quiet for years at the beginning of last century before restarting, Hathaway notes, so nothing out of the ordinary has happened - at least, not yet.

Another group at the US National Solar Observatory in Tucson, Arizona, William Livingston and Matthew Penn, believe that there may be a deeper process at work. Sunspots are highly magnetic regions that are somewhat cooler than the rest of the sun’s surface (they appear dark compared to the rest of the sun, but if seen separately would appear very bright) and the two researchers have been tracking both the temperature and magnetic strength of the spots. They found that the spots have been warming up and becoming less magnetic. An average of the trend is a straight line going down which hits the bottom of the graph at 2014. They have concluded that, although sun spots may appear briefly from time to time in the next few years, they will disappear by 2014.

This conclusion is in a paper submitted to the journal Science three years ago but rejected in peer review. With the sun now so quiet the paper has been resurrected from a filing cabinet in the observatory and circulated informally. Dr Livingston told me (by phone from his office in Tucson) that the paper had been rejected on the grounds that it was a purely statistical argument so it would be better to wait and see what happened, and he considered that a fair point. They are now waiting “for the right moment” to resubmit.

But what happens after 2014? Dr Livingston says that as they are using a purely statistical argument, without any theory to back it, they do not know. All they know is that the trend reaches zero in 2014. Conventional theory on the sun’s inner workings never forecast anything like this - in fact, forecast the exact opposite - but has been revised to say that the sun will restart some time next year.