The earth’s atmospheric composition is experiencing a perturbation unprecedented in recent history. Various human activities, including large-scale deforestation, fossil fuel harvesting and combustion, and industrial-scale crop fertilization have tremendously upset the planet’s carbon and nitrogen cycles and led to large increases in the atmospheric abundance of greenhouse gases. These changes are ongoing and dynamic. Anthropogenic emissions of pollutants and greenhouse gases are undergoing rapid alterations in response to technological, economic, and regulatory pressures. Natural sources and sinks are dynamically responding to the warming environment, with unknown feedback. We employ a combination of ground, airborne, and space-based observations to investigate both natural and anthropogenic sources of these atmospheric constituents. We link observations with models probing scales that span from cities to the globe, quantifying and attributing emissions. This leads to an improved understanding of carbon and nitrogen cycles which is crucial for future projections of climate and air quality and is necessary to inform societal responses and mitigation efforts.