One interesting aspect of the Sun is its sunspots. Sunspots are areas where the magnetic field is about 2,500 times stronger than Earth’s, much higher than anywhere else on the Sun. Because of the strong magnetic field, the magnetic pressure increases while the surrounding atmospheric pressure decreases. This in turn lowers the temperature relative to its surroundings because the concentrated magnetic field inhibits the flow of hot, new gas from the Sun’s interior to the surface.
Sunspots increase and decrease through an average cycle of 11 years. Dating back to 1749, we have experienced 23 full solar cycles where the number of sunspots have gone from a minimum, to a maximum and back to the next minimum, through approximate 11 year cycles. We are now well into the 24th cycle. So how much does the solar output affect Earth’s climate? There is debate within the scientific community how much solar activity can, or does affect Earth’s climate. There is research which shows evidence that Earth’s climate is sensitive to very weak changes in the Sun’s energy output over time frames of 10s and 100s of years.
But overall when examining Earth on a global scale, and over long periods of time, it is certain that the solar energy output does have an affect on Earth’s climate. However there will always be a question to the degree of affect due to terrestrial and oceanic interactions on Earth.
Source:
National Weather Service
National Oceanic and Atmospheric Administration
Sioux Falls, SD, USA
Sunspots recordings scanned from 35mm film courtesy of the Manila Observatory
Library and Archives