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Megan, Any connection to earths weather caused by sunspots?

Hello Megan,

 

There are a number of periods in the recorded history of sunspots where the SUn hardly produced any sunspots for several decades spanning a number of solar cycles.  The most famous of these is the Maunder Minimum which occurred between 1645 - 1715.  During this 70 year spell very few sunspots were seen on the solar disk.  This coincided with longer and deeper winters in northern Europe and North America.  The period from aroun 1200 (although there is a debate about when it actually started) to about 1850 is known as the Little Ice Age and contains the Maunder minimum as well as the Sporer minimum (1420 - 1570), Dalton minimum (1790 - 1830) and Wolf minimum (1282 - 1342). The Dalton minimum also had low sunspot numbers.  The Sporer and Wolf minima occurred before sunspot observations were being made routinely and are inferred from other sources associated with soalr activity such as carbon-14 radiodating and tree ring measurements.  

 

David 

Hi Megan, If sunspots are active, more solar flares will result creating an increase in geomagnetic storm activity for the Earth. Therefore during sunspot maximums, the Earth will see an increase in the Northern and Southern Lights and a disruption in power grids and radio transmissions. The storms can even change polarity in satellites which can damage sophisticated electronics. But its still not clear how much sunspots can (or do) affect the Earth's climate. Times of maximum sunspot activity are associated with a very slight increase in the energy output from the sun. Ultraviolet radiation increases dramatically during high sunspot activity, which can have a large effect on the Earth's atmosphere. From the mid 1600s to early 1700s, a period of very low sunspot activity (known as the Maunder Minimum) coincided with a number of long winters and severe cold temperatures in Western Europe, called the Little Ice Age. It is not known whether the two phenomena are linked or if it was just coincidence. The reason it is hard to relate maximum and minimum solar activity (sunspots) to the Earth's climate, is due to the complexity of the Earth's climate itself. For example, how does one sort out whether a long-term weather change was caused by sunspots, or maybe a coinciding El Nino or La Nina? Volcanic eruptions etc can also affect the Earth's climate by cooling the planet and burning of fossil fuels and cutting rain forests has the opposite effect. However, sunspot cycles have been correlated in the width of tree ring growth and perhaps this will provide us with more clues.