GEOG 1101 Lecture Notes - Lecture 7: Cloud Condensation Nuclei, Dew Point, Ice Crystals
7 Feb 2017
School
Department
Course
Professor
Document Summary
** clouds, fog, and dew all have 2 properties in common: 1) they must form from saturated or nearly saturated air. Rh = 100%, dew point t = air t . 2) they must have a surface (solid or liquid) upon which the water vapor can condense. Dew is the condensation event (water vapor changing to liquid water) wherein liquid water droplets form on the ground, vegetation, a car, or similar surface near the ground. Clouds & fog are condensation events wherein the droplets form suspended in the air. They form on particles known as condensation nuclei. * a condensation nuclei is a microscopic particle which is necessary as a surface on which water vapor condenses to form moisture droplets. These can be particles of dust, sea salts, soot, ash, sulfate & nitrate crystals, etc. * a hygroscopic nuclei is a condensation nuclei which is very water absorbent and usually of sulfate or nitrate crystals.
