Measurement of pernitric acid and inorganic bromine species using chemical ionization mass spectrometry

Abstract

Measurements of atmospheric trace gases is a central aspect of the study of atmospheric chemistry. It allows scientists to explore the atmosphere. Chemical ionization mass spectrometry (CIMS) has been utilized to measure atmospheric trace gases. This thesis presents two projects that involve CIMS measurements: measurements of pernitric acid (HO2NO2) in metropolitan Atlanta in winter 2014 and summer 2015, and airborne measurements of bromine monoxide (BrO) and the sum of hypobromous acid (HOBr) and dibromine (Br2) over the Tropical West Pacific during the CONTRAST campaign in 2014. HO2NO2 is in equilibrium with HO2 and NO2 at warm temperatures. This thesis illustrates the feasibility of inferring HO2 via HO2NO2 measurement at warm regions when HO2 measurements are unavailable. Bromine species are important ozone-depleting substances (ODS). The transport of inorganic bromine to the stratosphere, known as product gas injection (PGI) of bromine species, occurs in the tropics. PGI contributes to a significant part of stratospheric bromine loading. Measurements of inorganic bromine species over the Tropical West Pacific aids in better understanding the PGI processes.