The sunspot cycle is a natural occurrence every 11 years or so. It is the result of changes in the sun’s magnetic field. The solar cycle can affect us here on Earth, sometimes causing communications and electrical grid problems. We are currently in the developing stages of Solar Cycle 25, so we thought it would be an excellent space weather blog topic to talk about how the sunspot cycle affects us here on Earth.
As a side note, Cycle 25 is already beating projections, and it looks to be one of the more active cycles in recent memory. You’ll be hearing more about sunspots, solar flares, and auroras in the coming months! For the most part, there’s nothing to worry about — most of our experiences with the sunspot cycle are seen and not felt (the aurora borealis and aurora australis). But if you depend on GPS or satellite, knowing what the sun’s doing might be a good idea.
Let’s get started.
What is the sunspot cycle, and why does it occur?
The sunspot cycle is a periodic variation in the number of sunspots visible on the sun’s surface. Sunspots are dark regions that are cooler than the surrounding areas. They are caused by the sun’s magnetic field, which becomes more chaotic during peak sunspot activity.
The sunspot cycle occurs every 11 years, and scientists believe changes in the sun’s magnetic field are the cause. The sun’s magnetic field reverses every 22 years, which scientists believe causes the sunspot cycle. Overall, solar activity is quiet during the minimum and quite active during the peak.
How does the solar cycle affect us here on Earth?
The number of sunspots varies from year to year during a solar cycle, in most cases rising for the first 5-6 years, peaking, and then falling the following 5-6 years. The sunspot cycle affects us here on Earth in several ways. The most direct way is through changes in solar activity. Solar activity includes solar flares and coronal mass ejections (CMEs), with the radiation transported to Earth via the solar wind (see the above image).
These can disrupt communications, including radio and GPS signals, cause power outages, and damage electrical equipment. CMEs can also interact with Earth’s magnetic field, causing auroras (the Northern and Southern lights). The sunspot cycle may also affect the Earth’s climate, claim some scientists.
Changes in solar activity can influence the amount of sunlight that reaches the Earth. This can cause changes in atmospheric circulation patterns, affecting global climate.
What can businesses do to prepare for potential disruptions caused by the sunspot cycle?
The sunspot cycle happens when the sun’s surface becomes more active, causing sunspots to form, which produce solar flares — sometimes aimed at Earth. These flares — full of radiation — interfere with satellite signals, causing GPS systems to malfunction and disrupt satellite communications. The sunspot cycle causes disruptions to businesses that rely on GPS and satellite communications.
While the sunspot cycle is a natural phenomenon, businesses can take steps to prepare for potential disruptions. For example, companies that rely on GPS for navigation can develop backup systems that they can use in a sunspot-related outage.
Similarly, businesses that depend on satellite communications can work with their service providers to ensure backup systems.
What is the Carrington Event?
The Carrington Event was a massive solar storm that took place in 1859. It is named after British astronomer Richard Carrington, who observed the sunspot (and by chance the flare, reportedly) that triggered the storm, the largest in at least the past 500 years.
While the first flare was massive and began in the waning days of August 1859 with disruptions to telegraph equipment, the main show waited until September 1.
That day Carrington began drawing a sunspot that appeared on the sun’s surface. This sunspot was huge and active, and it released a massive “earth-directed” flare during Carrington’s observation. This energy caused a huge magnetic disturbance on Earth, which resulted in auroras as far south as the tropics, reportedly so bright in some areas that birds chirped in the middle of the night, and laborers started work believing the sun came up.
Space science was almost non-exists in the mid-19th Century, so some mistook it for the Biblical end of the world. But Richard Carrington knew the cause.
The effects of the Carrington Event, considered to be the most powerful solar storm in recorded history, were substantial. It caused telegraph lines to spark and catch fire, knocking out telegraph services across North America and Europe. If a similar storm happened today, it would cause $1-2 trillion in damage.
Luckily, the chances of that happening are pretty small.
Are people affected by the solar cycle?
The sunspot cycle is a well-documented phenomenon, and there is no doubt that it affects our sun. But what about us? Are people affected by the sunspot cycle?
There is some evidence that the sunspot cycle may influence human behavior. For example, studies have shown that suicide rates tend to rise during sunspot peaks. There are also anecdotal reports of increased irritability and difficulty sleeping during sunspot activity.
So while the solar cycle may not be a significant factor in our lives, it appears that it can subtly influence our mood and behavior. It might not be entirely in your head if you feel off during sunspot activity.