How do clouds and precipitation form?
1. Cooling of air as it rises leads to condensation (cloud formation). The Ref. Tables (p.15) show how temperature, humidity, and pressure vary with altitude. 2. Clouds result as condensation occurs when rising air is cooled to the dew point temperature and condensation nuclei (surfaces) are available. Rising air results from heating, convection currents, air moving up a mountain, or uplifting along a frontal boundary. 3. Precipitation occurs when cloud droplets or ice crystals join together and they become heavy enough to fall. Clouds can exist without having any precipitation take place. 4. Precipitation cleans the atmosphere by bringing down condensation nuclei and other suspended materials. Consider how clear air is after rain and acid precipitation. D. What Information is shown by weather maps? 1. An isoline connects places of the same value within a field. Temperature field and pressure field values can be modeled using isolines. 2. Strong winds are found in areas having steep pr
