Ice Nucleating Particle (INP) Concentrations and Treatment Data from Fairbanks, Alaska during the Alaskan Layered Pollution And Chemical Analysis (ALPACA) 2022 field study

These measurements were made as part of the Alaskan Layered Pollution And Chemical Analysis (ALPACA) field campaign, which investigated wintertime air pollution under cold, dark conditions in Fairbanks during January and February 2022. This dataset includes ice nucleating particle (INP) concentrations measured using an online and offline technique. Online INP measurements were made using a Continuous Flow Diffusion Chamber – Ice Activation Spectrometer (CFDC-IAS; Handix Scientific, Inc.). Offline INP measurements were obtained using the Colorado State University Ice Spectrometer (IS) from polycarbonate filter samples and size-resolved aerosol samples collected with a Davis Rotating-drum Unit for Monitoring (DRUM; model DA-400 DRUMAir™). For the offline filter and DRUM samples, heat and peroxide treatments were applied to estimate the contributions of INP types, including heat-labile organic, heat-stable organic, and inorganic INPs. In addition to ambient aerosol measurements, this dataset includes INP concentrations from local source materials, including lichen collected from spruce and alder trees and road gravel samples. Source samples were analyzed using the same treatment methods to characterize INP type and freezing behavior. Together, these measurements provide size-resolved and bulk INP concentrations, INP type classifications, and comparisons between ambient aerosols and local source materials during wintertime in Fairbanks during ALPACA. For more detailed information, please refer to: Greeney, S., E. Buxton, R. Perkins, S. Kreidenweis, P. J. DeMott, E. Costa, K. Pratt, L. Forshee, E. Levin, B. Temime-Roussel, B. D’Anna, K. S. Law, and J. Creamean: A comprehensive analysis of ice nucleating particles in a subarctic urban environment during the ALPACA campaign, Journal of Geophysical Research: Atmospheres, submitted, 2026.