St.-Maurice looks north to study link between solar weather & Earth
By Colleen MacPherson
Things are looking up for Jean-Pierre St.-Maurice. Way up.
The University’s Canada Research Chair in Environmental Sciences has his sights set on the Earth’s ionosphere over the Canadian Arctic. There, he will use new technology to examine how space weather generated by activity on the surface of the sun affects the Earth’s atmosphere and, by extension, life on this planet. For St.-Maurice, it is part of a multidisciplinary new push to take a broad look at environmental science, including climate change.
St.-Maurice’s research involves using a high frequency radar system called PolarDARN (DARN stands for Dual Auroral Radar Network) under development at the U of S Institute of Space and Atmospheric Studies. Once operational, the ground-based system will use intersecting beams to chart the electrical currents in the ionosphere, 100 km above the Earth. Created when gusts of solar wind collide with Earth’s upper atmosphere, these currents produce one of the great wonders of the night sky – the aurora borealis, or northern lights – but they also pose a potential threat here on Earth.
The professor of physics and engineering physics explained that massive storms on the sun’s surface send streams of high-energy particles racing through space at speeds of up to 2,000 km per second. As they approach our planet, the solar winds release new bursts of high-energy electrons and protons that pummel Earth-orbiting satellites “with enough persistence to cause satellites to lose attitude control, instruments to malfunction or cause it (the satellite) to shut down altogether,” he said.
On Earth, electromagnetic impulses delivered from the always-changing currents in the ionosphere can create currents on the ground capable of destroying power installations such as transformers. History has shown this damage can trigger a domino effect that leads to power failure across grids. Also at risk are welds on pipelines that can corrode or spark when these currents pass through them.
The Earth’s climate can also feel the effects of space weather. St.-Maurice said it has long been known a link exists between activity on the sun and Earth’s climate so it is key to understand more about that dynamic star. New technology, particularly the SOHO spacecraft (Solar and Heliospheric Observatory), “has already completely changed how we look at the sun. For example, we used to think the activity on the sun was an 11-year cycle but we also know that cycle can stop altogether, and we have not a clue as to how this happens. What we do know is that when the cycle stops, the northern hemisphere gets a lot colder.”
He points out that the aurora can, like the sun, “be very structured or very erratic. To me, I think of these systems as behaving like milk poured into hot coffee after you’ve given it a little stir. You see clouds and swirls forming complex patterns – the aurora, and even the solar cycle, show similar kinds of turbulent structures.”
Understanding and predicting the effect of major solar events on our planet “means we’ll be able to help people shield their satellites, shut down their power networks in vulnerable areas when necessary, even to divert flights away from higher latitudes when necessary to protect people from radiation. Our knowledge will certainly be useful, and sometimes critical because when the big one (solar explosion) strikes, we’re going to have a lot of the problems mentioned earlier with satellites and the like. Even the ozone layer stands to be damaged by violent solar explosions.”
St.-Maurice’s choice of the high Arctic to do his work is key because there, the resistance offered by Earth’s magnetic field is at its weakest and the atmosphere most susceptible to penetration by the particles carried on solar winds. Mapping the electric fields there “and relating them back to solar activity will give scientists better insight into the connections between our planet and its life-sustaining star.”
As research continues and knowledge grows, St.-Maurice, in his role as Canada Research Chair, sees himself as a catalyst for an environmental science and climate change theme at the U of S. It will require “true collaboration” with people from many disciplines “to explore the origins of climate change, its effects and possible fixes. And this includes the social sciences. Think about it – climate change can affect the geopolitical map, can spark wars and can bring on famine and drought. We all need to be involved in this issue.”