The Northern Lights: more than just a beautiful phenomenon

In March 2023, cities across the Greater Toronto Area (GTA) and Southern Ontario witnessed a striking display of coloured lights in the night sky due to a rare occurrence of the Northern Lights – a phenomenon typically expected in higher latitude regions, closer to the North or South Pole.

“The event that many people witnessed in the GTA was caused by a relatively weak geomagnetic solar storm,” says Afshin Rezaei-Zare, associate professor in the Electrical Engineering and Computer Science department at York University’s Lassonde School of Engineering, who focuses his research on geomagnetic disturbances (GMD) and their impacts on society and technological infrastructures. “Strong solar winds from the storm pushed the sun’s particles deeper in the atmosphere, ionizing more gases and moving them to lower latitudes than we usually expect; that is why we could see these lights in the GTA.”  

Solar winds are streams of materials from the sun, mainly charged particles like electrons and protons, that can come in contact with Earth’s magnetic field and collide with gases in the Earth’s atmosphere, emitting the flares of light that are commonly known as the Northern Lights. 

Northern Lights in Bruce Mines, Ontario, October 2022. Photo provided by @avinography

“When the Earth’s magnetic field is hit by coronal mass ejections and intense solar flares, similar to but stronger than what happened in March, they can cause geomagnetic disturbances in addition to expanded northern lights,” says Professor Rezaei-Zare. “This can have a widespread impact on technology, even damaging things on the ground level.”  

Geomagnetic disturbances are potentially dangerous fluctuations in the Earth’s magnetic fields, causing geomagnetically induced current (GIC) to flow through ground-level power systems, transmission lines and transformers. GICs can overwhelm these systems with thermal stress, damaging their functionality and leading to harmful effects such as large-scale power outages – an occurrence of this was witnessed in Quebec in 1989 when a strong geomagnetic storm left the entire province without power for more than nine hours! 

Professor Rezaei-Zare focuses his research on taking preventative measures and understanding the effects of space weather and resulting geomagnetic disturbances to help develop protection for vulnerable ground-level technologies. Using calculations, modelling techniques and computational tools, Professor Rezaei-Zare analyzes the impacts of geomagnetic disturbances on various power systems, identifying components that are vulnerable to malfunction or damage from geomagnetically induced current. This research provides crucial knowledge to manufacturers and power utility companies, allowing them to identify and protect their vulnerable equipment to better prepare for the potential effects of solar storms. Professor Rezaei-Zare’s contributions are also well-received and incorporated in technical guides and standards for power equipment. 

In his recent and ongoing research, Professor Rezaei-Zare has investigated the impacts of geomagnetically induced current on various equipment and systems, including transformers, generators, protection systems, renewable resources, and High-Voltage DC (HVDC) systems. Most of these studies have been the first-in-kind in scientific literature. The results reveal potential threats, solutions, and research and development opportunities for making power grids and equipment resilient to the effects of space weather.

“The GMD research is becoming more and more important, but there are very few experts in the field because of how many disciplines are involved in understanding this single area of research,” says Professor Rezai-Zare. “I want to use my combined expertise to stimulate knowledge and increase understanding of this unfamiliar field.”  

Leading research teams with domestic and international members and collaborators, Professor Rezaei-Zare continues to work towards understanding geomagnetic disturbances and their impacts on power systems, to protect Earth from the harmful effects of solar storms and space weather. His current research activities are supported by grants awarded from NSERC Discovery, Alliance and Idea-to-Innovation, as well as programs including, MITACS, Tri-agency New Frontiers in Research Fund (NFRF), and Ontario Center of Innovation. Lassonde continues to support Professor Rezaei-Zare’s unique work, encouraging the intersection of academic disciplines to establish crucial knowledge in this niche area of research.