GEOG 101 Lecture Notes - Lecture 30: Urban Heat Island, Stormwater, Vapor Pressure
Document Summary
Several studies show that urbanization can increase cloudiness and enhance precipitation. The enhanced land surface roughness of cities. In many cases urban effects are enhancements of pre-existing clouds or storms rather than initiation of new storms. The urban effect is most evident during warm summer weather with light winds when the frequency of thunderstorms is increased in and downwind of cities. Once rain or snow reaches a city, not all facets receive the same amount. The spatial distribution of rainwater and snow deposition is highly variable owing to microscale airflow anomalies that are accentuated in cities. Technically, we distinguish between p (precipitation) that falls directly on the ground and that intercepted by the roofs and walls of buildings as well as tall vegetation. The amount and distribution of urban trees is also important to determine how much and how fast rainwater reaches the ground.
