Made Fun and Digestible for the 16-year-old Geography Wiz!

Urban areas have their own mini-weather patterns, called microclimates.

What factors affect these microclimates?

• Air Structure: More dust means more tiny particles (hygroscopic) in the air, less water vapor but more CO2 and nasty fumes. Think of a busy city during rush hour - all those cars pumping out exhaust gases!
• Surface Structure: The urban surface is full of heat-retaining materials with low albedo (they don't reflect light/heat well) and excellent radiation-absorbing properties. Imagine dark asphalt on a sunny day - it gets hot, right?
• Urban areas also have a variety of slopes and surfaces, from skyscraper rooftops to shady alleyways.

Radiation & Sunshine: Dust scatters short-wave radiation but absorbs long waves due to surfaces and CO2, creating more diffuse sky radiation (less clear, more spread out). It's like a natural light show! There can be less visibility due to the industrial haze (kind of like a dusty curtain).

Clouds & Fogs: There are more clouds in summer and more fogs or smogs in winter due to convection and pollution. Hygroscopic particles help with condensation, making it quicker. Day temperatures can be 0.6°C warmer on average.

Temperatures: The city holds onto heat, thanks to materials and fuel combustion. This creates heat "islands" where it's warmer than in the suburbs. Think of it like a warm blanket around the city center. There are big contrasts between sunny and shaded areas.

Pressure & Winds: Buildings cause gusts and turbulence, with local pressure differences from one side to the other. Narrow streets can be calm unless wind funnels through them (the "canyon effect").

Humidity: Usually decreases due to less available moisture and higher temperatures. In very cold conditions, condensation can happen early in low-lying and industrial areas.

Precipitation: More intense storms in summer evenings and nights. Possibly more thunder. Less snowfall and brief snow covers.