Professor’s work shines light on Northern Lights

Northern Lights

In March 2023, cities across Southern Ontario witnessed a rare occurrence of the Northern Lights. A source of wonder for many, for Afshin Rezaei-Zare, associate professor in the Electrical Engineering and Computer Science department at York University’s Lassonde School of Engineering, it was an example of the focus of his research on geomagnetic disturbances (GMD) and their impacts on society and technological infrastructures.

“The event that many people witnessed in the Greater Toronto Area was caused by a relatively weak geomagnetic solar storm,” says Rezaei-Zare. “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,” he says, explaining the event.

Afshin Rezaei-Zare
Afshin Rezaei-Zare

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. There is more to them, however, than a beautiful sight.

“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 Rezaei-Zare. “This can have a widespread impact on technology, even damaging things on the ground level.”

Rezaei-Zare’s work focuses on how those 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. His research aims to focus on taking preventative measures and understanding the effects of space weather and resulting geomagnetic disturbances to help develop protection for vulnerable ground-level technologies. Those technologies which can be overwhelmed with thermal stress, damaging their functionality and leading to harmful effects such as large-scale power outages, as occured in Quebec in 1989 when a strong geomagnetic storm left the entire province without power for more than nine hours.

Using calculations, modelling techniques and computational tools, 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.

In recent and ongoing research, much of it first-of-its-kind scientific literature, 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.

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, allowing for updates to technical guides and standards for power equipment.

Leading research teams with domestic and international members and collaborators, 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.

“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 Rezai-Zare. “I want to use my combined expertise to stimulate knowledge and increase understanding of this unfamiliar field.”