Scientists and observers who have watched the sun have noticed certain trends for sunspots. There is a connection between chemical processes in the sun and the amount of solar flares and spots that can be observed. There is a cycle that lasts about eleven years of solar activity. During the periods of greatest activity there is a measurable increase in solar radiation that can affect objects outside of the Earth’s atmosphere. This is a major concern for sensitive electronic equipment and astronauts.

 The atmosphere is an effective shield for this type of radiation. However, those who live far enough north can see a colourful interaction between the radiation and the atmosphere late at night. This cosmic light show has to do with the release of light energy as the radiation goes around the planet. It is called the northern lights and there is always more activity after an increase in solar flares.

The cycle of activity seems to suggest that there is also a variation in the amount of energy released by the sun. While there are measurable differences in the amount of light and energy given off by the sun, the result is unnoticeable on the surface of the planet. In addition to the obvious seasonal changes from the Earth’s revolution around the sun and the tilt of the axis, there are variations in the path of the orbit. These factors have a far more limiting effect than minor changes in radiation from the sun.

The concerns that exist about solar radiation have more to do with the wavelength of the radiation. Studies show that wavelengths of light that fall into a narrow range on ultraviolet light are particularly harmful. This range of light only makes up about three percent of all the light that hits the Earth, but a small increase can have a significant effect. Most of the ultraviolet light is absorbed by a layer of the atmosphere that is rich with a chemical variation of oxygen called ozone. Ultraviolet light is known to damage DNA and increases of 10% are associated with a 25% more cases of skin cancers.

Environmental factors on the planet have had a significant effect on the ozone layer, which has led to an increase in ultraviolet radiation that reaches the surface. An increase in atmospheric carbon dioxide is causing a reaction that reduces ozone, and this is the subject of much debate as to the cause, with some claiming it is mostly down to man’s combustion of carbon rich fossil fuels, while there is much evidence of natural events such as sunspot activity having the greatest effect. There are also measurable differences in the solar cycle on the amount of ultraviolet radiation. Interestingly, there is a chemical reaction in gaseous oxygen in the atmosphere and ultraviolet radiation. During the periods of greater ultraviolet radiation, the reaction creates more ozone and as the radiation decreases, so does the ozone.

A great deal of scientific study is being done on several factors to see if natural variations or human influences are causing climate change. After a period where proper scientific debate was being stifled by a section of society who were profiting by encouraging people to believe the change in climate was solely down to man’s influence, we are finally entering a period where more open debate is starting to take place and proper scientific study is beginning which includes the many natural events that affect the climate such as solar activity, volcanic activity and earthquakes.