The ability of atmospheric aerosols to impact climate through water uptake and cloud formation is fundamentally determined by the size, composition, and phase (liquid, semi-solid, or solid) of individual particles. Particle phase is dependent on atmospheric conditions (relative humidity and temperature) and chemical composition, and importantly, solid particles can inhibit the uptake of water and other trace gases, even under humid conditions. Particles composed primarily of ammonium sulfate are presumed to be liquid at the relative humidities (67-98%) and temperatures (-2 to 4 °C) of the summertime Arctic. Under these atmospheric conditions, we report the observation of solid organic-coated ammonium sulfate particles representing 30% of particles, by number, in a key size range (
Published: April 15, 2022
Citation
Kirpes R., Z. Lei, M. Fraund, M.J. Gunsch, N.W. May, T.E. Barrett, and C.E. Moffett, et al. 2022.Solid organic-coated ammonium sulfate particles at high relative humidity in the summertime Arctic atmosphere.Proceedings of the National Academy of Sciences (PNAS) 119, no. 14:Art. No. e2104496119.PNNL-SA-160900.doi:10.1073/pnas.2104496119