Why environmental chemistry research?

Climate forcing
Greenhouse gases—such as water vapor, carbon dioxide, methane, chlorofluorocarbons (CFCs), and nitrous oxide—trap heat radiating from our planet's surface. To better understand just how human activities are changing our planet's radiative energy balance, CIRES scientists measure the heat-absorbing properties and lifetimes of greenhouse gases and ozone. Ozone plays a particularly important role in controlling the overall chemistry of the atmosphere and the lifetimes of chemically active gases like methane.

We also investigate how the chemical composition of aerosols may influence the earth's temperature. By examining how different aerosols reflect the sun's radiation, we're able to estimate how they affect the heat balance of the atmosphere. In addition, aerosols appear to affect the planet's temperature indirectly by acting as nuclei for water condensation, facilitating cloud formation. Clouds, depending on their height and thickness, can either deflect radiation or trap it. Improving our understanding of the role of aerosols in influencing cloud formation and cloud radiative properties will vastly improve global climate modeling forecasts.

Air quality
Ground-level ozone and aerosols are two major contributors to air quality problems. Through regional field campaigns, laboratory studies, and modeling investigations, CIRES researchers study the production, transformation, and transport of these air pollutants, enabling us to provide essential guidance to decision-makers on effective air quality management. Our research has helped demonstrate that air pollution must be understood on local to regional levels and that flexible management strategies are critical. For instance, the most effective approach to improving air quality on a regional basis is often dependent on the balance between the natural and human-made sources of the oxides of nitrogen and volatile organic compounds in that particular area. This type of information has spurred new strategies for managing large industrial point sources of pollution and controlling multiplesource pollution in cities like Houston, Texas.

Stratospheric ozone
When the ozone hole was first discovered over Antarctica, CIRES researchers played a key role in illuminating the chemical nature of the problem. Since then, we have continued to monitor stratospheric ozone around the globe, to investigate the processes that can alter it, and to help develop safer chemical alternatives to CFCs—the main chemical culprit behind ozone depletion. A particularly active area of CIRES research concerns the connection between aerosols and the CFC-related chemical depletion of ozone. Ongoing laboratory measurements, field studies, and modeling allow us to improve the accuracy of our predictions concerning ozone layer recovery.

Research Snapshot
Biomedical Science and Global Health Applications