GEOG 131 Chapter Notes - Chapter 4.9, 4.11-4.15, 5.15-5.16: Return Period, Fog, Freezing Rain
Document Summary
Fog- ground level cloud that obscures visibility: forms where the addition of moisture occurs simultaneously with the chilling of air. Evaporation fog- increase in humidity and cooling causes the rising air to reach saturation. Valley fog- if moisture is added to valley air the humidi ed and cooled air can reach the dew point. Radiation fog- cooling of the ground surface by radiant heat loss. Advection fog- air cooling to the dew or frost point the moisture in the air will condense and produce fog. Upslope fog- caused by the upslope motion of air. Condensation nuclei- water particles condensing around even tinier particles. Collision-coalescence- larger rain drop overtaking the smaller droplets on their descent, making them larger. Bergeron process- liquid water > water vapor > ice > drops. Freezing rain- precipitation that reaches the ground as raindrops but immediately freeze upon contact with cold objects on the surface.
