Where Have all the Sunspots Gone?

If you’re a HAM radio buff, chances are you have been making some long distance connections over the last few weeks with very little interference from the upper atmosphere.  You owe thanks in part to the solar wind, or a lack thereof. 

Blowing outward from the sun at nearly 400 km/s, the solar wind normally moves around the earth’s magnetic field like water around a boulder in a stream.  As the solar wind slides past the outer areas of the magnetic field, strong electrical currents are generated that flow into the earth’s upper atmosphere, often producing electrifying aurora displays.  During intense solar storms, strong solar winds are capable of crippling satellites and causing havoc for radio and television transmissions.

Currently, however, the sun is going through a very quiet time.  So quiet in fact that astronomers, physicists and climatologists are wondering about the long term effects on the earth and its inhabitants if it continues. 

The sun normally goes through an 11 year cycle of solar storm activity.  At its peak activity during the cycle, as many as 100 sunspots can be visible at any one time.  It is during this time that satellite operators and communication engineers are pulling their hair out trying to keep viewers and listeners happy.  Slowly, over the next 5 1/2 years of the 11 year cycle, the sunspots slowly disappear.  During the solar cycle minimum, it is possible to not have a single sunspot on the surface of the sun.  Communications are great on earth and auroras are weak, and usually visible only in Polar Regions.  This minimum is usually short lived with sunspots appearing in the middle latitudes shortly after the last ones disappeared, indicating the new cycle has started. 

The last solar minimum occurred during 2007, indicating that we should be well into the next solar cycle, but that has yet to happen.  The sun’s face is currently bare of sunspots, auroras are minimal and communications are great.  While there is an upside to the lack of sunspots, there could be a downside that we know very little about.

The current lack of sunspots is the lowest since we began accurate solar observations during the 1950s, and no one is sure what to expect.  The last suspension of the solar cycle, known to astronomers as the Maunder Minimum, coincided with the “little ice age” which occurred from 1645 to 1715.  The temperature of the earth cooled only 1 degree Kelvin, but the effects were devastating.  Crops failed around the globe and thousands of people perished.  Frost Fairs were held in London on the Thames River when the ice was thick enough to support festivities; French vineyards were affected and it created harsh conditions for American troops at Valley Forge.

Scientists believe that the solar cycle helps to keep the earth at a somewhat steady temperature.  However, if the sunspots fail to reappear, a solar inactivity period of only ten years is enough to put the earth back into a deep freeze.  Given the current climate change the earth is experiencing due to global warming, this potential period of global cooling could be a blessing in disguise while we get our act together on implementing alternative energy sources.  However, if mankind doesn’t reduce its carbon signature on the planet, the cooling will only be temporary, and the temperatures will rise again.