Human activity and natural processes can have measurable impacts on atmospheric composition and indoor air quality. These emissions can have impacts on the earth’s climate system, outdoor and indoor air quality, and other negative outcomes. An important focus of research in the DeCarlo Research Group involves the characterization of aerosol particles (also called particulate matter or PM). These particles, 100x smaller than the width of human hair, are damaging to health, have a major impact on the climate, affect visibility, and can damage fragile ecosystems. These detrimental effects are controlled but the concentration, composition, size, and shape of these particles. Research topics in my group generally fall under the topics listed below.
Field Studies to Measure Atmospheric Composition:
Field studies are opportunities to do intensive measurements of a large suite of both particulate and gas-phase pollutants. These measurements are typically collaborative, with many researchers working together to sample and analyze as many different chemical species as funding will allow. The results of these campaigns are used to understand the system in which all of these species interact and provide observable insight into the complex processes of the atmosphere.These studies are done anywhere there is an interesting science question or research need. The picture above is the Kathmandu Valley in Nepal during the NAMaSTE 2 campaign, and the picture below is a much cleaner part of the world: Antarctica near McMurdo Station.
Advanced Instrumentation Development and Characterization:
Advances in our understanding of particulates or gas phase species in our atmosphere often require new instrumentation or methods to measure them. Instrument development and characterization with scientific collaborators in industry and other research groups worldwide are key to moving us forward in our understanding of these chemical species in our atmosphere. Sometimes we get to test new instruments in different ways like … canoeing.
Particulate sources to the atmosphere include primary sources such as industry, vehicles, domestic/household burning, and biomass burning. Source measurements allow us to look for chemical signatures in the emissions that can be linked to measurements made in the field. Additionally they can be used to understand the impact a source is expected to have on an urban area, a national park, or the atmosphere at large.
The Indoor Environment:
We spend the vast majority of our time indoors, and consequently our exposure to air pollutants mostly happens in the indoor environment. Work in the DeCarlo Group in collaboration with other indoor air quality researchers examines the composition of particulates and gases in the indoor environment to better understand the transport of pollution from outdoors indoors, as well as identifying indoor sources of pollution.
Laboratory studies allow us to isolate a process we would like to study under controlled conditions. Laboratory studies are often used to motivate field research, but can also be used to verify or study processes observed in the field measurements. One example of laboratory research is the use of small or large chambers to study processes such as the formation of particles from reaction of volatile organic compounds with oxidants such as ozone or radical species.