One of the lesser talked about but no less important phenomena that makes Earth habitable is its continental crust, which is unique in the Solar System.
The weathering of continental rock draws down carbon dioxide from the atmosphere and eventually gets locked up in the rocks themselves, explains Thomas Chacko, metamorphic petrologist in the Department of Earth and Atmospheric Sciences.
“If that didn’t happen, the Earth would be a runaway greenhouse,” says Chacko. “Without this feedback loop, the CO2 would just increase and we would become like Venus, where the surface temperature is 400 C.
“And while plate tectonics is key in forming new continental crust today, the processes by which continental crust formed in the first 2 billion years of Earth history and the role that this played in making our planet habitable still need answers,” he says.
Understanding what it is about the Earth that allowed the continental crust to form and created this delicate life-reliant balance is at the heart of Chacko’s remarkable 30-year academic career at the U of A. It has led to Chacko being awarded one of the university’s highest honours: the 2020 University of Alberta Distinguished Professor.
“Thomas Chacko is a prolific educator, scientist, and leader in the Faculty of Science,” says Matina Kalcounis Rueppell, dean of the Faculty of Science.
“His work fostering positive and authentic student experiences, and combining these experiences with groundbreaking research, embodies the values of the University of Alberta. I am delighted to join our entire community in congratulating Thomas on this well-deserved recognition.”
To receive this distinction, a professor’s scholarly work must have merited international recognition, their teaching and student supervision must be highly esteemed by colleagues and students, and they must be regarded as exceptional citizens.
“I know some of the people in the Faculty of Science who previously won this award, and I hold them in the highest regard,” says Chacko. “To be numbered in their company is really gratifying.”
And while the research papers that bear his name and thousands of citations from colleagues around the world are a testament to his research, Chacko says he hopes his legacy is his mentorship.
“I’ve tried not to separate research and teaching because I think they’re intimately linked. I’ve always felt that the most important contribution we make as academics is what we invest in our students, both at the undergrad level and at the graduate level,” Chacko says.
“Ultimately, most of our research has a shelf life of anywhere between five and 20 years, whereas those students that we invest in, they’re going to make contributions for 30 to 40 years.”
Chacko was awarded the Faculty of Science’s Graduate Mentor Award and has won every major teaching award at the U of A, including the Faculty of Science Undergraduate Teaching Award, the Rutherford Teaching Award, and one of the first two Vargo Teaching Chairs when they were established in 2003.
As well, all five of his former PhD students are in tenured or tenure-track faculty positions.
He attributes his success in the classroom to a strong belief that in order to be an effective teacher, one must have a genuine concern and respect for students as people and a sincere desire to help them learn.
“When students start their academic careers, you’re teaching them more than they teach you. But you can see a transition, especially over the four or five years of a PhD student,” he says. “By the end, you’re listening to them, and they’re teaching you more than you teach them.”
Born in India, Chacko emigrated to the U.S. when he was seven and grew up in New Jersey. He did his undergraduate at Rutgers, a master’s at Penn State, and a PhD at the University of North Carolina, Chapel Hill.
He completed a three-year post-doctoral fellowship at the University of Chicago before arriving in Edmonton in January 1990.
“In the back of my head I thought ‘I’ll stay a few years and then I’ll go someplace warmer,’ but it’s a really strong department with wonderful colleagues. And despite the six months of winter, Edmonton is actually a very nice city to live in.”
Besides serving as a longtime associate chair of the department, Chacko has worked closely for more than 15 years with the Northwest Territories Geological Survey to set up a NWT field school. This field school gives senior-level undergraduate students training in geological mapping of a remote area and a spectacular wilderness experience in the Canadian North.
The award comes with a generous research stipend of $20,000 a year for three years, which Chacko says he would like to put toward his research and bolstering the field school.
“For geologists, all the work starts in the field. To look at how the rocks are distributed on the outcrop scale, that’s always the beginning of any laboratory study.”