Alfonso Mucci awarded Royal Society of Canada’s Miller Medal

Emeritus Professor called “an internationally renowned geochemist who has made numerous contributions in geochemistry and biogeochemistry”
Professor Alfonso Mucci (left) and PhD student Olivier Sulpis aboard the Coriolis II in 2017, sampling waters in the St. Lawrence Estuary for dissolved oxygen analyses. Louise Delaigue

The Royal Society of Canada (RSC) has today announced the award of the 2020 Willet G. Miller Medal for Ocean Sciences to Emeritus Professor Alfonso Mucci of McGill’s Department of Earth and Planetary Sciences.

The RSC applauded the oceanographer as “an internationally renowned geochemist who has made numerous contributions in geochemistry and biogeochemistry.”

“He has revolutionized the application of spectroscopy in understanding crystal growth mechanisms in solution, developed models of metal behaviour in marine sediments, documented and identified the causes of bottom-water hypoxia in the St. Lawrence Estuary, a likely trigger to the demise of the Eastern Canada fish stocks, as well as predicted the deep-sea sediment response to the uptake of anthropogenic CO2 by the oceans,” the RSC’s citation reads.

“This is well-deserved recognition for Professor Mucci,” said Martha Crago, Vice-Principal, Research and Innovation. “His work on the acidification of our oceans and their role as a long-term carbon sink has advanced our knowledge of the dangerous extent of climate change.”

The medal, among Canada’s most prestigious honours in ocean science, comes at a poignant moment in Mucci’s career, barely two weeks on from his retirement after 35 years at McGill.

“It’s a great honour and a capping achievement to a career. It’s also a bit humbling when you look at previous medal winners. There’s some big names in the field,” said Mucci, as he paid tribute to a list of Miller Medal predecessors, from plate tectonics pioneer John Tuzo Wilson, who received the honour in 1955, to more recent recipients, including McGill’s Anthony Williams-Jones (2011), and UQAM’s Anne de Vernal (2016), with whom Mucci has collaborated closely.

From chemistry to oceanography, from Les Escoumins to Miami

Mucci built his career in marine science on a foundation in physical organic chemistry. An avid scuba diver who spent vacations exploring the sub-zero depths of the St. Lawrence River at Les Escoumins, Mucci recalls the moment when, as a master’s student at the Université de Montréal, he heard a professor mention oceanography as one field in which analytical chemistry could be used.

“It just hit me right there, and I said, ‘Okay, that’s what I want to do.’” Mucci said. “So I started looking at the literature, looking for physical chemists who were working in the marine environment.”

His search led him to doctoral studies at the University of Miami under the supervision of Frank Millero and the late John Morse, who came to be a mentor and close friend to Mucci.

“He was very supportive, and he really propelled my career,” Mucci said. “I remember, in the second year of my PhD, within a period of a month, I spent 50 hours on planes, flying to different conferences and giving talks. John introduced me to all the high flyers in the field.”

Back to the St. Lawrence

Despite the appeal of Miami’s warm waters and the convivial US research community of which he had become a part, Mucci was drawn back to Canada by NSERC’s University Research Fellows program. He took up an assistant professorship at the Université du Québec à Rimouski in 1983. Two years later, he moved to McGill.

Fast forward another 20 years and Rimouski would again be an important staging point for Mucci – this time as the home port of the RV Coriolis II, a Coast Guard vessel converted, thanks to an ambitious CFI-funded project, into a state-of-the-art marine research vessel. It was aboard the Coriolis II that Mucci carried out much of his groundbreaking work documenting the development of severely hypoxic bottom waters in the St. Lawrence Estuary and the mechanisms and impact of ocean acidification on sediment chemistry.

Venturing beyond the backyard

Mucci describes the St. Lawrence, the world’s biggest estuary, as “like having an ocean in your own backyard”. From 2003 onwards, he extended his work on acidification and bottom sediments to the Arctic Ocean aboard the research icebreaker CCGS Amundsen.

“My first realization of how vast the ocean was, was on the maiden voyage of the Amundsen,” he said. Returning to the ship from a helicopter survey of the fjords on the east coast of Baffin Island, Mucci was struck by how small the 100-metre-long ship appeared: “It was a tiny little thing in this humongous, vast ocean.”

An aura of excellence

For all his intrepid exploits, Mucci puts greatest emphasis on the people who have supported him throughout his career.

“I have had some amazing graduate students, who have ended up having amazing careers of their own. I have had a very dedicated technician, Constance Guignard, for 25 years,” he says. “And, of course, my family, my wife, who has been incredibly supportive of me working all the time.”

McGill, where Mucci has worked for the past 35 years, has been no less of a driving force in his career: “There’s this aura of excellence at McGill, and it just propels you, it carries you along. You don’t find it everywhere.”