Gas phase hydrogen peroxide is an important species within the odd-hydrogen family of oxidants in the atmosphere, especially with regard to controlling important hydroxyl radical levels and initiating heterogeneous aqueous phase oxidation of sulfur dioxide in fog or cloud. These chemical reactions have profound effects on atmospheric composition and Earth system climate. Currently available methods for the detection of hydrogen peroxide at trace atmospheric levels suffer from relatively slow temporal response. Through this project the investigators will further develop and test the Atmospheric Pressure Ionization Mass Spectrometry technique in the laboratory to make measurements of atmospheric gas phase hydrogen peroxide at data rates and lower limit of detection amenable to use on aircraft. Such a new fast-response measurement capability would bring hydrogen peroxide measurements more into line with other available fast response measurement techniques for odd-hydrogen species in the atmosphere and in doing so generate new insights into a variety of important atmospheric photochemical cycles. The broader impact of this project lies in developing a technique application addressing a compelling need within the odd-hydrogen measurement community, with results likely to have an important impact on future atmospheric composition and climate change research. The project also supports the professional development of an early-career postdoctoral researcher.
