This image shows wind speeds and directions over a segment of the ocean. The red color denotes faster wind speeds while the blue color denotes slower wind speeds. Scientists once wondered if changes in the Sun affected wind patterns on Earth. Click on image for full size (3 Kb) Courtesy of U.S. Navy/NRL/NOAA

The solar cycle, the rise and fall of the number of sunspots on the Sun, has been known since the mid-19th century. Soon after this discovery scientists started to ask how solar variability might affect the Earth's weather.

The solar cycle goes from when the Sun has a minimum number of sunspots (a solar minimum) to when the Sun has a maximum number of sunspots (a solar maximum) back to a minimum. The time between two minimums is about 10.5 to 11 years. Solar activity is related to the solar cycle. Because solar activity (such as coronal mass ejections) is more frequent at solar maximum and less frequent at solar minimum, geomagnetic activity also follows the solar cycle.

Attempts to find correlations between this solar cycle and the Earth's weather proved very difficult. Although this may in part be related to variable weather data quality and the wide range of weather phenomena, it is most likely due to the lack of a significant physical relationship between the solar cycle and Earth’s weather.

One example was a study to see if the solar cycle affected wind patterns on Earth. In 1949, H.C. Willett looked to see if the solar cycle affected long-term variations of wind patterns. He saw the solar cycle as a definite factor in influencing wind variations. He did admit that, "the physical basis of any such relationship must be utterly complex, and is as yet not at all understood." However attempts to confirm his conclusions were not successful.

In fact, over time and with more and more studies and more sophisticated instruments (especially satellites outside the Earth's atmosphere), connections between solar variations and Earth's weather have been found increasingly unlikely. Another result that has withstood some but not all challenges is an apparent connection between solar cosmic rays and Earth's cloudiness.

Through decades of study by scientists around the world, Sun-weather connections have largely been rejected by the scientific community.

This image shows wind speeds and directions over a segment of the ocean. The red color denotes faster wind speeds while the blue color denotes slower wind speeds. Scientists once wondered if changes in the Sun affected wind patterns on Earth. Click on image for full size (3 Kb) Courtesy of U.S. Navy/NRL/NOAA

The solar cycle, the rise and fall of the number of sunspots on the Sun, has been known since the mid-19th century. Soon after this discovery scientists started to ask how the solar cycle might affect the Earth's weather.

The solar cycle goes from when the Sun has a minimum number of sunspots (a solar minimum) to when the Sun has a maximum number of sunspots (a solar maximum) back to a minimum. The time between two minimums is about 10.5 to 11 years. Really all aspects of the Sun and solar activity are influenced by the solar cycle. Solar activity (like coronal mass ejections) is more frequent at solar maximums and less frequent at solar minimums.

Scientists tried, but were not able to find correlations between this solar cycle and the Earth's weather. These attempts to find correlations ran into many difficulties. One problem was that weather data quality was variable. Finally, most scientists concluded that there is most likely no significant physical relationship between the solar cycle and Earth’s weather.

One example was a study to see if the solar cycle affected wind patterns on Earth. In 1949, H.C. Willett looked to see if the solar cycle affected long-term changes of wind patterns. He saw the solar cycle as a definite factor in influencing wind variations. He did admit that, "the physical basis of any such relationship must be utterly complex, and is as yet not at all understood." However, attempts to confirm his conclusions were not successful.

In fact, over time and with more and more studies and better instruments (especially satellites outside the Earth's atmosphere), connections between the solar cycle and Earth's weather have been found more and more unlikely. One exception to this seems to be that solar cosmic rays do affect Earth's cloudiness.

Through decades of study by scientists around the world, Sun-weather connections have largely been rejected by the scientific community.

This image shows wind speeds and directions over a segment of the ocean. The red color denotes faster wind speeds while the blue color denotes slower wind speeds. Scientists once wondered if changes in the Sun affected wind patterns on Earth. Click on image for full size (3 Kb) Courtesy of U.S. Navy/NRL/NOAA

The solar cycle is the rise and fall of the number of sunspots on the Sun. Sometimes there are lots of sunspots and sometimes there are few sunspots. Scientists know that solar activity (like coronal mass ejections) is higher when there are more sunspots. Last century, scientists started to ask how the solar cycle might affect Earth's weather.

Scientists tried, but were not able to find correlations between the solar cycle and the Earth's weather.

One example was a study by Willet in 1949 to see if the solar cycle affected wind patterns on Earth. He saw the solar cycle as a definite factor in affecting wind variations. However, attempts to confirm his conclusions were not successful.

Over time, with more and more studies and better instruments (especially space satellites), connections between the solar cycle and Earth's weather have been found to be unlikely. In fact, through much study by scientists around the world, Sun-weather connections have largely been rejected by the science community.