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
Courtesy of U.S. Navy/NRL/NOAA
Sun's Effect on Earth's Weather (Wind)
from the Sun
is one of the primary drivers of the Earth system
. The Sun warms our planet, heating the atmosphere
. This energy feeds atmospheric processes and is a primary driver of our weather
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.
Shop Windows to the Universe Science Store!Cool It!
is the new card game from the Union of Concerned Scientists that teaches kids about the choices we have when it comes to climate change—and how policy and technology decisions made today will matter. Cool It! is available in our online store
You might also be interested in:
Once energy from the Sun gets to Earth, several things can happen to it: Energy can be scattered or absorbed by aerosols in the atmosphere. Aerosols are dust, soot, sulfates and nitric oxides. When aerosols...more
Surprisingly, humans have observed sunspots for a very long time, so historical sunspot observations provide us with some of our best long-duration records of solar activity. Large sunspots can sometimes...more
The Sun is not a quiet place, but one that exhibits sudden releases of energy. One of the most frequently observed events are solar flares: sudden, localized, transient increases in brightness that occur...more
"Without warning, the relatively calm solar atmosphere can be torn asunder by sudden outbursts of a scale unknown on Earth. Catastrophic events of incredible energy...stretch up to halfway across the visible...more
In conducting their research, scientists often want to know if two sets of data (variables) are related to each other. For instance, you might wonder if the amount of time a student spends reading the...more
Clouds can come in all sizes and shapes, and can form near the ground or high in the atmosphere. Clouds are groups of tiny water droplets or ice crystals in the sky and are formed by different processes....more
The study of space weather is a relatively young science. As such it has many unanswered questions and unsolved mysteries. Although some of our data relevant to space weather, such as sunspot counts, go...more
IMF stands for Interplanetary Magnetic Field. It is another name for the Sun's magnetic field. The Sun's magnetic field is enormous and is carried by the solar wind. The solar wind and magnetic field are...more