A recent and unexpected decline in sunspot activity has scientists and the media speculating about potential effects on the earth’s climate, including a possible cooling trend if the sunspot drought proves long-lived.
According to an Associated Press article this week, sunspot activity typically follows a 12-year cycle of high and low periods. But occasionally the cycle is disrupted and the sun enters extended “hibernation” periods that can last for several decades. The primary effects sunspots or solar flares have on earth are disruptions to satellite communications and other electronic systems as the charged particles reach our atmosphere. At least some scientists believe, though, that high or low sunspot activity could affect heating or cooling trends on earth.
The news isn’t entirely new. During the Cattle-Fax outlook seminar ar the 2011 Cattle Industry Convention in February, Creighton University Professor Art Douglass mentioned this trend, saying sunspot activity appeared to be entering a long-term decline. Douglass noted that a similar trend in solar activity corresponded with the “Little Ice Age” that occurred during the 17th and 18th centuries.
But not all scientists agree on whether sunspots have much effect on the earth’s climate. Quoted in an AP article, Andrew Weaver, a climate scientist at the University of Victoria, says any temperature effect would be more than offset by man-made global warming from greenhouse gasses. He says solar activity was mostly absent during 2010, which scientists say was one of the Earth’s hottest years on record.
The article also cites a study finding an extended low period of solar activity would reduce Earth’s temperatures by no more than 0.3 degrees Celsius by the end of the 21st Century, while another report from the Intergovernmental Panel on Climate Change forecasts global temperatures will increase by as much as 4.5 percent during this century.
Other scientists question whether current understanding of solar cycles is reliable enough to predict any trend in solar activity. This quiet period could just be a short-term dip.
So it’s probably too early to invest in space heaters, snow shovels and goose-down futures, but on the other hand, maybe not the best time for that trip to the Arctic Circle to view the Aurora Borealis.
Read more from the Associated Press.