Professor Martin is the coordinator of the atmospheric science program and director of the Atmospheric Composition Analysis Group at Dalhousie University, and is a Research Associate at the Harvard-Smithsonian Center for Astrophysics. His research focuses on characterizing atmospheric composition to inform effective policies surrounding major environmental and public health challenges ranging from air quality to climate change. He leads a research group at the interface of satellite remote sensing and global modeling, with applications that include population exposure for health studies, top-down constraints on emissions, and analysis of processes that affect atmospheric composition. His group's work has been featured as Paper of the Year by the leading journal Environmental Health Perspectives. Data from his group are used for the OECD Regional Well-Being Index, for WHO estimates of global mortality due to fine particulate matter, for the Global Burden of Disease Project to examine the risk factors affecting global public health, and for the Environmental Performance Index, and for a wide range of health studies. Martin served as the scientific co-chair of a recent IGAC/iCACGP international conference on atmospheric chemistry. He currently serves as Co-Model Scientist for the GEOS-Chem model, on the WMO Global Atmosphere Watch Task Team for Observational Requirements, on the Outdoor Air Pollution Expert Working Group of the Global Burden of Disease Project, and on several satellite Science Teams. He leads the SPARTAN network to evaluate and enhance satellite-based estimates of fine particulate matter. His professional honors include a Steacie Memorial Fellowship and selection to the Royal Society of Canada. Google Scholar reports over 25,000 citations of his 200 journal publications.