It’s not just our Earth that experiences seasonal changes. According to a new study conducted by researchers at the National Center for Atmospheric Research (NCAR), the Sun too experiences seasonal changes. The discovery may help researchers better forecast space weather events like solar storms. The Sun undergoes a seasonal variability as its activity increases and decreases over a course of about two years.
The seasonal change affects the peaks and valleys
This seasonal change affects the highs and lows in the approximately 11-year solar cycle. It sometimes amplifies and sometimes weakens the solar storms that can affect our planet’s atmosphere. Researchers said these variations are largely driven by changes in the bands of magnetic fields in each solar hemisphere.
Scott McIntosh, director of NCAR’s High Altitude Observatory, likens these bands in the Sun’s magnetic field to the Earth’s jet stream, a river of air encircling our planet. These bands also shape the 11-year solar cycle, which is part of a longer 22-year cycle. According to scientists, the rotation of the Sun’s deep interior causes overlapping of these bands.
Scientists want satellites to monitor the Sun’s weather
As the bands move in the Sun’s northern and southern hemispheres, solar activity peaks over a period of 11 months before beginning to wane. These bands carry opposite magnetic activity. The occurrence of solar flares is at its peak when the bands are far apart. Researchers were able to detect the ring-shaped, twisted bands by analyzing data from NASA satellites and ground-based observatories that gather information about the Sun, solar flares and coronal mass ejections (CMEs).
Findings of the study will help scientists predict solar storms better. Solar storms can sometimes disrupt power grids, satellite operations, communications, GPS and other technologies. McIntosh said that if you are in the military or running a satellite, you would want to know when the Sun is going to blast off a flare. He recommended building a series of satellites to monitor the Sun’s weather, just like the Earth’s weather is tracked.
Findings of the study were published in the journal Nature Communications.