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The Solar Cycle's Effects on Earth's Weather

At the center of the solar system, the sun is responsible for providing the Earth with light and warmth. Scientists have long been fascinated by the relationship between the sun and the Earth, and for more than 100 years have tried to figure out if it has any effect on the planet's weather or climate. There have been many arguments both for and against, but there is still no definitive answer.

Sunspots
- Dark flecks on the surface of the sun are known as sunspots. They are relatively cooler than the rest of the sun's surface, and can remain for anywhere from a few days up to a few weeks. They are magnetic regions with their own magnetic fields, and they tend to be grouped in two sets of ten spots. One set has a positive (or north) magnetic field, the other negative (or south). The magnetic field is strongest in the darkest area of the sunspot.
Solar Cycle
- The solar cycle is the rise and fall of the number of sunspots on the surface of the sun. The number of sunspots is directly related to solar activity, so when the number of sunspots increases, solar activity grows. The energy given out by the sun also increases with the number of sunspots. The waxing and waning of the number of sunspots was documented by monthly averages, and it was discovered that there is an approximate 11-year cycle. During this cycle, the total energy given off by the sun varies by 0.1 percent.
History
- Galileo Galilei made the first European observations of sunspot numbers in 1610. Although his are the first records, regular observations began at the Zurich Observatory in 1849. During the 17th century, a period of inactivity was recorded, known as the Maunder Minimum. Between the years 1645 and 1715, very few sunspots were recorded, and this coincided with the "Little Ice Age." During this time, rivers froze and snow remained all year at lower elevations. It is thought that sunspot inactivity may have contributed to this phenomena.
Climate
- Studies into the links between solar activity and Earth's weather continue. It is thought that the activity of the sun and its solar cycles do not directly affect the Earth's weather, but may have a more general effect on the global climate. The variation of the sun's energy of 0.1 percent over an 11-year cycle is not enough to bring about the changes in temperature recorded around the world in recent times. This has also been influenced by greenhouse gases and thus is not a true reflection of the effects of solar cycles.

Astronomy