Carbonyl compounds play central roles in the photochemistry and organic chemistry of the atmosphere, but little is known about their concentrations and cycling. Nearly all past measurements of carbonyl compounds in clean air over remote regions were restricted to formaldehyde, even though other carbonyl compounds were probably present at similar or higher concentrations. The main objectives in this project are to elucidate the major sources and sinks of a wide variety of carbonyl compounds in the remote troposphere and to quantify these roles in tropospheric chemistry. To achieve these goals, the PI plans to perform intensive measurements of background concentrations of gas and aqueous phase carbonyl compounds, and to study their variations with respect to chemical and meteorological conditions. The work will be carried out as a part of the Mauna Loa Observatory Photochemistry Experiment II. The simultaneous measurements of key compounds and parameters during this program will provide significant new information needed for modeling tropospheric chemical processes, which in turn will provide new insights into the relative importance of carbonyl compounds in tropospheric chemistry.
