Do Sunspots Affect Earth’s Climate?
During sunspot maximums, solar radiation increases a small percentage. However, ultraviolet radiation increases significantly, and solar flare activity, which is generated in the regions between spots, increases greatly. Flares are extremely hot ejections of plasma.
We have just come out of sunspot maximum 23 (beginning counting in 1749), which peaked in 2000 with 170 spots a day—a highly active cycle. It was during this time that ‘Global Warming’ became a rallying cry for environmentalists. We are now in the minimum part of the cycle. (See the NASA prediction graph below.)
This year, China saw its' coldest winter in 40 years, Florida the coldest in 30 years. Europe experienced the coldest winter in 25 years—all this according to ABC News.
But there is another clue that sunspots may have an affect on our climate. In that count of sunspot maximums, there is a period between 1645 to 1715 when sunspots were almost nonexistent (sunspots were being counted then but not on a daily basis as was begun in 1749). This is known as the Maunder Minimum.
During these 70 years, the Earth was cast into what’s called the ‘Little Ice Age.’ Global average temperatures dropped more than two degrees F. Are such minimums the cause of the major ice ages Earth has experienced in its geologic past?
NASA predicts the next sunspot maximum (24) will occur in 2014, but that it will be considerably weaker than 23. Could this foretell a cooler climate?
To be fair and balanced, there is no overwhelming evidence that sunspots are the gremlins of Earth’s climate. Many other factors could enter the equation. For example, our planet wobbles on its axis. Its average tilt is 23.5 degrees, but over a period of 18.6 years that varies from 22 degrees to 24.5 degrees. That changes the amount of solar radiation that each hemisphere receives.Then there are El Nino and La Nina.
Perhaps they all make their own mischief. Let's consider more mysteries of the sun in the next section.