GEOG 122 Lecture Notes - Lecture 25: Urban Heat Island, Smog, False Creek
Document Summary
Urbanisation and climate: air pollution initially localised and intermittent, caused by natural and human fires in forests and greenland, also in and around the few large cities. In addition cities decrease wind speeds, increase cloud and fog cover, decrease solar radiation and increase extreme precipitation events (hail, thunderstorms) Role of topography ( relief") and a temperature inversion in creating a smog trap; in. La inversion happens 35 40% of the year, creating a smog lid". Temperature inversion: cooler air at around, warmer air above it: when this happens, air currents do not rise and gets trapped. Types of air pollution: first generation pollution: sulphur base fuels in false creek, vancouver 1930s. Second generation, post industrial smog during a temperature inversion in fraser. Dominant winds coming from west and funnelled eastwards. Leading to isolines (line of equal value) with principle ozone concentration downwind of vancouver in fraser valley. As you go eastwards (of vancouver), there is more pollution.
