Abstract
The variations of ice nucleus and ozone concentrations were monitored at a high mountain observatory in the Colorado Rockies. Because the observatory is at an altitude of nearly 4 km MSL, increases in ozone at this station are in most instances related to intrusions of stratospheric air into the troposphere. An increase of ice nuclei simultaneously with an increase of ozone in such cases would therefore be indicative of a transport of ice nuclei from the stratosphere to the earth's surface. High ice nucleus concentrations in stratosphere air would substantiate the possibility of an extraterrestrial nucleus source. A negative correlation between the ozone and ice nuclei existed during the time of the case study presented. It is concluded that at least during this period there was not an influx of ice nuclei simultaneously with a downward transport of stratospheric air. Hypotheses for a ground origin of ice nuclei are supported.
