Corey Jones
Updated September 21, 2009 at 12:50am
The average person may not associate coolness with the sun.
The sun releases energy through deep nuclear fusion reactions in its core and has surface temperatures as hot as 10,000 degrees Fahrenheit, according to NASA's Web site.
Not cool at all. But the sun's recent activity, or lack thereof, may be linked to the pleasant summer temperatures the midwest has enjoyed this year, said Charlie Perry, a research hydrologist with the U.S. Geological Survey in Lawrence.
The sun is at a low point of a deep solar minimum in which there are little to no sunspots on its surface.
In July through August, 51 consecutive days passed without a spot, one day short of tying the record of 52 days from the early 1900s.
As of Sept. 15, the current solar minimum ranks third all-time in the amount of spotless days with 717 since 2004. There have been 206 spotless days in 2009, which is 14th all-time. But there are still more than 100 days left in the year, and Perry expects that number to climb.
Perry, who studies sunspots and solar activity in his spare time, received an undergraduate degree in physics at Kansas State University and a Ph.D in physics and astronomy at The University of Kansas. He also has spent time as a meteorologist.
A sunspot, Perry explains, is a location on the sun's surface that is cooler than the surrounding area. When there are more sunspots, the sun's surface becomes more dynamic and an opposite effect takes place, releasing more heat and energy when other parts of the sun become hotter.
A solar minimum is when the amount of spots on the sun is at a low and the reverse is true for a solar maximum. The complete solar cycle is about an 11-year process. Perry says the current solar minimum could continue into 2010.
"There's a fair chance it will be a cooler winter than last year," Perry said.
Perry said there is a feeling from some in the scientific community the Earth may be entering into a grand minimum, which is an extended period with low numbers of sunspots that creates cooler temperatures. The year without a summer, which was 1816, was during a grand minimum in 1800 to 1830 when Europe became cooler, Perry said. Another grand minimum was in 1903 to 1913.
Perry said there is anecdotal evidence the Earth's temperature may be slightly decreasing, but local weather patterns are much more affected by the jet stream than solar activity.
However, Perry said snow in Buenos Aires and southern Africa, the best ski season in Australia and a cooler Arctic region are some of the anecdotal evidence for a cooling period.
So, Perry said, sunspots may have a far greater impact on weather than previously thought.
Perry is a proponent of the cosmic ray and clouds theory as opposed to the CO2 global warming theory to explain recent global warming trends.
The cosmic ray and clouds theory was first put forth in the late 1990's by Danish physicist Henrik Svensmark.
In a July 2007 issue of Discover magazine, Svensmark said the theory is simply that solar activity can alter the amount of clouds in the atmosphere, which affects the temperature of the Earth. More clouds mean a cooler Earth because more of the sun's heat is being reflected. Fewer clouds equal a warmer Earth.
Perry says data indicates global temperature fluctuations correlate to a statistically significant degree with the length of the sunspot cycle. Longer cycles are associated with cooler temperatures.
Johan Feddema, acting chair and professor of geography at KU, studies global warming. Atmospheric science is a program in geography at KU. He says he is skeptical of any one phenomenon being the direct cause of global warming because there are so many climate variables that factor into global temperatures.
Feddema said the warming trend earlier in the century could be attributed to anything from solar activity to El Ninos. But since the mid 1980s he believes data doesn't correlate well with solar activity, but does correlate well with rising CO2 levels.
Feddema believes we may hit global high temperatures in a few years with the underlying factor being rising CO2 levels, coupled with the solar cycle returning to a maximum and an El Nino.
For more information or to view graphs of data pertaining to global climate change, Feddema recommends visiting the Intergovernmental Panel on Climate Change's Web site at www.ipcc.ch/ where 2007 assessment reports on climate change can be viewed. He also recommends the Wikipedia entry on solar variation for good visual graphs of data.
Perry said he recommends www.icecap.us/ for climate information; www.discovermagazine.com to learn more about Svensmark's theory; www.global-warming-and-the-climate.com/images/sunspot-lenght-&-teperatur... to view a global temperature and solar activity graph; and his own research Web page at ks.water.usgs.gov/waterdata/climate/.
Corey Jones can be reached at (785) 295-5612 or corey.jones@cjonline.com.
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