Ice Nuclei in Seawater, Fog Water and Marine Air off the Coast of Nova Scotia: Summer 1975

Abstract

Ice nuclei were measured in seawater, fog water and the free atmosphere from 28 July to 11 August during the 1975 Hayes Fog Cruise off the east coast of Nova Scotia, Canada. Some seawater samples were found to contain ice nuclei active at ?4 to ?5°C, although the majority of seawater samples contained no nuclei active at temperatures warmer than ?14°C. Half of the fog water samples contained ice nuclei active at temperatures warmer than ?10°C; some nuclei were active at ?2°C. Atmospheric ice nucleus concentrations varied from 1.1 to 580 nuclei m?3 active at ?15°C. Some bacteria isolated from fog water were observed to initiate ice at ?1.5°C. High concentrations of active ice nuclei in seawaters and fog waters were associated with high concentrations of biological materials in the same samples.