"We had long conversations," recalled Svoboda, now 78 and retired from his position as a professor of botany at the University of Toronto.

"We would speak about how the world was much more than its mechanics – it was much deeper than that. Everyone – even the younger students – felt that the ground we walked on was holy."

That "holy groundƒ could be the Sverdrup Pass, a tundra-and-rock covered valley on Ellesmere Island high up in the Arctic Archipelago where the closest neighbours were a herd of muskox. Or Devon Island, just to the south. Or on the shore of Baker Lake in what is now Nunavut just west of Hudson Bay. In such places, nature is master and humans realize quickly how fragile and vulnerable life can be.

Svoboda, the scientist, found no conflict with Svoboda, the devout Roman Catholic, in such places.

"In my particular life history, I believe in spite of my scientific training. . . . Once you believe in God, you find Him everywhere."

God was certainly in the tundra, in the gentle breezes of the Arctic summer, even in the occasional snowfall in July. While Svoboda and his team of researchers were thoroughly scientific and arrived with many backgrounds and beliefs, the sense of the sacred was never far away.

Nor was their growing sense of concern that the environment they so loved was changing. Slowly, but clearly, each year they found increasing evidence that global warming was having its way with Canada's high Arctic. They saw it in the more rapid growth of tiny plants such as the Arctic avens and in the retreat of glacial ice.

Svoboda is aware of the scientific controversy over the causes of global warming. What he believes is undebatable is that increasing carbon dioxide in the environment is causing irreparable harm.

"Yes, there is a fight over the reasons for global warming," he says. "It doesn't matter. Carbon dioxide is increasing, Arctic ice is melting, oceans are rising. The social impact will be enormous. The strong nations will do well while the poorer, less developed nations will suffer greatly. Let's do what we can to slow it down and talk about its causes afterward."

Svoboda believes that humanity's footprint on the global environment has become so all-encompassing that we can no longer usefully talk about a "biosphere." Instead, he calls it a "homosphere," a planetary environment that is completely dominated by human activity.

"The biosphere is under the management of man. We are entrusted to be stewards but we've done a very poor job. For our own sake, it is important to allow nature to not only survive but to flourish."

Svoboda finds motivation for his environmentalism not only in his science but also in his Christian faith. This faith was forged in his native Czechoslovakia during the Second World War and honed in the crucible of Communist oppression.

He had begun to study biology and philosophy at Masaryk University in 1948-49 where he became involved in student underground politics. In 1949 he was arrested by the Communist authorities for what he recalls as minor and naive activities against the regime, and ended up in prison, sentenced to 11 years of hard labour.

He spent three years working in a uranium mine before being transferred to Leopoldov prison, where he spent a short time in solitary confinement. Slowly, he began to make contact with priests in the prison and learned there was a special lockup just for clergy. By telling a prison guard that he was a priest, Svoboda engineered his transfer into this area. There he discovered a clandestine seminary where priests, bishops and professors taught theology and philosophy and prepared young men for ordination. He spent two-and-a-half years there before he was moved to another prison.

Though he received his seminary training, he was never ordained. Instead,  he was released from prison in 1958 and, after trying to get back into university for years with only marginal success, he fled to Canada in 1968. He was readily accepted as a 37-year-old political dissident.

Once in Canada, he resumed his biology studies at the University of Western Ontario in London. After his undergraduate work, he moved to the University of Alberta in Calgary, where he completed a doctorate, using his thesis to do valuable research in the Arctic.

By the fall of 1973 he was on faculty at the U. of T. and on his way to a long career in Arctic studies.

Over the years, he has built an impressive international reputation, publishing more than 60 scientific papers, developing a system of hothouse farming of vegetables in the Arctic and charting the accumulation of radioactive fallout. He continues to lecture widely, freely combining science with a fervent love of the North and concern for its spiritual as well as physical health.

Despite being immersed in the scientific world all those years, the Catholic Church was never far away. This was especially true in Svoboda's northern adventures. His very first trip as a professor leading a small group of students took him to Repulse Bay in what was then the Northwest Territories and is now Nunavut. There he was met by Oblate Father Mascaret, who offered the use of his mission house as accommodation.

He came to know and love many of the Oblate missionaries, men who had devoted their lives to working with the aboriginal peoples in Canada's North and West. He especially got to know Fr. Theophile Didier, who spent a large part of his life translating the New Testament and liturgical texts into Inuktitut. He also became good friends with Bishop Omer Robidoux, OMI, of Churchill-Hudson Bay diocese, who died in a 1986 plane crash.

Through the years, Svoboda and his students enjoyed the hospitality of the Oblates and spent many nights being regaled by their stories of life in the harsh Arctic climes. On special occasions, Oblate priests would visit their camps to celebrate Eucharist with them.

Today Svoboda lives a very active retirement in Burlington, Ont., with his wife, Lewina, and enjoys watching from afar his son Michael raising his own family from his home in the Yukon Territory. He also remains an active parishioner, helping with the Rite of Christian Initiation for Adults and other parish ministries at St. John the Baptist Church.

Thirty-two years of summers in the high Arctic have permanently marked Svoboda in ways he will always treasure. He was already a scientist and a Catholic before; his northern exposure turned him into a Christian environmentalist.