Real-time analysis of insoluble particles in glacial ice using single-particle mass spectrometry

Abstract

Abstract. Insoluble aerosol particles trapped in glacial ice provide insight into past climates, but analysis requires information on climatically relevant particle properties, such as size, abundance, and internal mixing. We present a new analytical method using a time-of-flight single-particle mass spectrometer (SPMS) to determine the composition and size of insoluble particles in glacial ice over an aerodynamic size range of ∼ 0.2-3.0 µm diameter. Using samples from two Greenland ice cores, we developed a procedure to nebulize insoluble particles suspended in melted ice, evaporate condensed liquid from those particles, and transport them to the SPMS for analysis. We further determined size-dependent extraction and instrument transmission efficiencies to investigate the feasibility of determining particle-class-specific mass concentrations. We find SPMS can be used to provide constraints on the aerodynamic size, composition, and relative abundance of most insoluble particulate classes in ice core samples. We describe the importance of post-aqueous processing to particles, a process which occurs due to nebulization of aerosols from an aqueous suspension of originally soluble and insoluble aerosol components. This study represents an initial attempt to use SPMS as an emerging technique for the study of insoluble particulates in ice cores.

Analytical challenges and advancements in measuring individual mineral nanoparticles and microparticles entrapped in ice cores

“…Single particle mass spectrometry (SPMS) has been used since the 1990s to measure particles in the modern atmosphere in realtime (Noble and Prather 2000). In the only reported use of SPMS to measure particles in ice cores (Osman et al 2017), long sampling times (>1 hour) and more than 100 mL of liquid sample were required, which can be a limitation in analyzing ice cores with small sample volume. Furthermore, SPMS typically does not quantify the amount of each element in a particle.…”