1. Clouds and Their Formation

2. What is a cloud? A Cloud consists of condensed water vapor, ice and dust (aerosols) There are three main types: cumulus, stratus, and cirrus

3. Requirements for cloud formation : Condensation Nuclei: small suspended particles or aerosols which the water vapor condenses on (ex: dust, pollen, sea salt) Saturated air (with water- relative humidity is 100%)

4. Recall: The Water Cycle

6. What Happens? As air rises it expands (less pressure on it) and cools It cools without any energy input or adiabatically It reaches the dew point, and the water vapor condenses The opposite is true in a sinking air mass- it compresses and warms Ice crystals can form if the atmospheric temperature is below 0 ºC

7. Draw this out:

8. Let’s Sum up: Create a flow chart showing the steps in cloud

9. cloud types (see diagram) dew: water condenses on ground surface frost: water condenses and freezes on surface fog: cloud at ground level

10. Water droplets coalesce (grow together) and get too heavy to stay in the air- so they fall as rain types of precipitation include: rain,drizzle, freezing rain(reaches a cold pocket of air and freezes upon contact with a surface), sleet (snow and rain mixed), hail(ice spheres that begin in a cloud as snow or rain and melt and gather moisture as they fall), and snow (deposits) When will it Rain?