A clearer picture of Earth's atmosphere

Randall Martin keeps his eyes on the skies to tackle two hot-button issues: human health and climate change.

The Dalhousie professor behind the world's first satellite-based estimates of global ground-level pollution has won the NSERC (Natural Sciences and Engineering Research Council of Canada) E.W.R Steacie Memorial Fellowship.

The $250,000 award, announced Monday, will allow Dr. Martin to continue improving his estimates of ground-level pollution, get a better understanding of the effects of human activity on climate and gain insight into the emissions to the atmosphere of different trace gases and particles.

Helping solve two issues at once

Dr. Martin's team uses satellite observations of sunlight that has passed through the atmosphere to infer the abundance of trace gasses and particles. Knowing where pollutants are means that Dr. Martin and his team can determine their impact.

"If pollutants are close to earth's surface, they're of relevance to human health. Pollutants higher up in the atmosphere are still relevant for climate," he says. "Satellite remote sensing is like looking down on a murky bucket of water. You don't know where in the atmosphere the pollution is, so we use a model to calculate the vertical profile of pollutants in the atmosphere."

Before Dr. Martin's team began their project, global estimates of ground-level pollution were made using econometric models, since many of the world's most populous regions have sparse instrumentation. Dr. Martin took it upon himself to get a clearer picture.

"Using satellite remote sensing to complement ground instrument measurements filled a major void in understanding pollution concentrations near the earth's surface," he explains.

His estimates have attracted attention from some of the world's leading health bodies, including the World Health Organization (WHO), who is using Dr. Martin's estimates for their Global Burden of Disease analysis. This assessment is providing evidence that millions of people die from air pollution each year.  

Health Canada used Dr. Martin's dataset in conjunction with the long-form census to study cardiovascular mortality from exposure to fine particulates and found the association occurred at a much lower limit than previously demonstrated – suggesting that even low exposure to pollutants can cause cardiovascular issues.

A researcher garnering attention

The science community has acknowledged Dr. Martin as one of the world's leading young atmospheric scientists.

"Randall is deeply committed to developing our knowledge of the global atmosphere," says Chris Moore, dean, Faculty of Science at Dalhousie. "The impact of his research has far-reaching significance for health and the environment. He has already made more contributions in his short career than many scientists do in a lifetime and is highly deserving of the award."

Given the amount of time Dr. Martin dedicates to understanding the natural world, it is not surprising that his commitment to a healthy environment extends beyond his academic life. He bikes to work every day (including the winter) and notes air pollution plays a role in his decision to live in the Maritimes.

"The air quality in Halifax," he beams, "is excellent."

Up to six Steacie Fellowships are awarded annually to enhance the career development of outstanding and highly promising young scientists and engineers who are faculty members of Canadian universities. With this award, Dr. Martin joins an elite group including two recent Dalhousie winners, Boris Worm (2011) and Andrew J. Roger (2007).