Our meteorologist, Mark Sirois, explains what a solar cycle is and why it matters
In early 2020, the current solar cycle, No. 25, began. In 2022, the solar activity associated with this cycle has outperformed forecasts. What happens if this trend continues? How do solar cycles affect our weather and our planet? How much of our climate change can be attributed to the ebbs and flows on the surface of the sun? Let’s try to answer these questions…and more.
The solar maximum is expected sometime around July 2025
The sun and its influence on weather forecasting and climate
When I build my long-range forecasts for Harrowsmith, I analyze four influences that impact global
temperatures and climate. Those are (1) volcanic activity; (2) ocean patterns, such as El Niño and La
Niña; (3) carbon dioxide levels in the atmosphere; and (4) solar activity. These influences are widely accepted
by scientists globally. Although it is hard to say how much impact solar activity has on our weather over a
short period of time, we can measure the impact that solar cycles have on our climate over a period of years,
decades and more. I will give examples later on.
What is a solar cycle?
What does the number 25 represent? A solar cycle, in simplest terms, is a
period of solar activity, or inactivity, that lasts approximately 11 years from beginning to end. If we think of the sun as a giant, complex magnet whose magnetic fields are constantly on the move, every 11 years the north and south poles flip. Within each 11-year cycle, there is a solar minimum and a solar maximum. The solar minimum refers to the lowest amount of solar activity within the cycle, and inversely, the solar maximum represents the highest amount of activity within the cycle. Although solar cycles have existed since the beginning of time, the first recorded cycle began in February 1755 and lasted 11.3 years.
Now, 267 years later, we find ourselves at the early stages of cycle No. 25.
What kind of activity do we see during a solar cycle?
Just like on Earth, the sun experiences its own weather. It goes through periods of calm and then enters
stormy periods. On Earth, we have tornadoes, hurricanes, derechos, blizzards and so on. On the sun, there
are four main types of storms: solar flares, coronal mass ejections (CMEs), high-speed solar winds, and solar
energetic particles.
Solar flares are sudden and quick eruptions of intense high-energy radiation from the sun’s surface. These are most associated with sunspots and can cause electromagnetic disturbances on Earth (i.e., radio frequency disruptions and power outages). Solar flares are categorized according to strength. The weakest is A, followed by B, C, M, and the largest, X. Even X-flares have categories to measure intensity. In 2001, there was an X-17 flare, which was the strongest ever recorded, but it was not directly aimed at Earth.
Coronal mass ejections are large ejections of plasma from the sun’s corona. They can eject billions of tons of coronal material and carry an implanted magnetic field. CMEs travel outward from the sun at speeds
ranging from less than 250 kilometres per second (km/s) to as fast as near 3,000 km/s. The fastest Earth-directed CMEs can reach our planet in as little as 15 to 18 hours.
High-speed solar winds are a stream of charged particles released from the sun’s corona.
Solar energetic particles are an observable intensification of electrons, protons and heavy ion fluxes at energies well above the average thermal energy of solar winds.
How does all of this affect Earth?
Solar flares at an M- and X-classification could produce auroras at midlatitudes, which means Southern Canada and the northern U.S. could view the northern lights if conditions are clear. M-class flares can also cause radio blackouts at the poles here on Earth. X-class flares are major events that can disrupt satellites and communications on Earth, and if an X-class flare is strong enough, it can bring down power grids.
In March 1989, an X-16 flare occurred that knocked out the entire Hydro Quebec grid for 9 hours. It also
caused an aurora borealis, which was seen as far south as Florida. Since 1989, many power utilities have
upgraded their systems to be able to counter such strong solar flares, but they haven’t really been tested since then. Although the X-17 flare in 2001 was the strongest ever recorded, it was not directly aimed at Earth like the 1989 X-16 flare was, so we still have to wait to see if we can handle the big stuff.
Outside of the individual flares and CMEs, an abnormally active solar cycle could contribute to a period of
higher temperatures globally for a period of years. The same can be said for a period of abnormal inactivity.
The Little Ice Age
Between 1645 and 1715, Earth experienced something called the “Maunder Minimum.” This was an
abnormal period of very weak solar cycles with very few sunspots on the sun. It was named after astronomer
Edward Maunder, who shone light on the fact that for those 70 years very cold winters occurred while there
was little to no solar activity. During those 70 years, average temperatures dropped 1 to 2 degrees Celsius. This caused shorter growing seasons and crop failures. Did inactivity with the sun really cause the Little Ice Age? Some scientists claim that an increase in volcanic activity around the globe could have caused it. My perspective is that it was likely a perfect storm of volcanic ash in the upper atmosphere limiting the amount of sunlight coming from a weakened sun over a period of decades. What we know for sure is that nothing is certain as to whether another little ice age is heading our way.
Solar cycle No. 25 — what’s next?
As of the writing of this article (late May 2022), the current solar cycle has outperformed both cycle No. 24
and the forecasts that had initially been released by NASA in 2019. We have seen many M- and X-class flares
with midlatitude auroras on several occasions. We are still very early in this cycle, and the solar maximum is expected sometime around July 2025. Between now and then, could we see flares close to the 1989 flare? Will we see Earth progressively get warmer, aided by increased CO2 levels? I think it is very likely. Without being a conspiracist, I think we are on the doorstep of a historical period for climate as well as for the things we take for granted every day. Let’s talk in 10 years and see if I’m right.
Related posts:
Mark Sirois is a managing partner at Kyndryl by day and a long-range meteorologist whenever he can fit it in his free time. His passion for meteorology started at age 15, and for the last 35 years, he has developed a multifaceted approach to long-range forecasting. His frustrations with the way Canadian mainstream media broadcasts weather information led him to create an alternative option to those in southern Quebec. Since 2007, he has offered severe and long-range forecasts through the Southern Quebec Severe Weather Network on Facebook; but since 2022, he now provides daily, weekly and seasonal forecasts for Quebec as The Weather Whisperer via patreon.com/TheWeatherWhisperer.
