Studies of ice nucleation by Arctic aerosol on AGASP-II
- Cite this article as:
- Borys, R.D. J Atmos Chem (1989) 9: 169. doi:10.1007/BF00052831
Aerosol particles were collected on filters for studies of their ability to nucleate ice during the second Arctic Gas and Aerosol Sampling Program (AGASP-II) in April, 1986. The ice nuclei (IN) samples were collected from an aircraft at altitudes ranging from the surface to the vicinity of the tropopause in Arctic locations over Alaska, northern Canada and Greenland. Samples of other components of the aerosol were collected and measurements were made of other properties of the aerosol coincident in time with the IN samples. The IN filters were exposed to water saturation in a dynamic developing chamber at −15° C and −25° C. Ice crystals grew on the IN and were counted on the filters at discrete time intervals during the exposure period to determine the rate of ice nucleation and the final concentration of (IN). Results show that Arctic haze aerosol, identified by pollutant signatures, had lower IN concentrations, a lower IN to total aerosol fraction and slower ice nucleation rates than aerosol which had a chemical signature more indicative of the remote unpolluted troposphere. These observations suggest that the Arctic haze aerosol does not efficiently form ice in the arctic troposphere. This may be a factor contributing to the long-range transport of Arctic haze.