Download Water in the Air study guide KEY

Water in the Air Study Guide
1. Be able to define vocabulary terms in your own words. USE QUIZLET
2. Why is water the most important gas for atmospheric processes?
It’s involved in the formation of clouds, precipitation, dew, fog…. All parts of the water cycle.
3. What does it mean if air is saturated?
100% relative humidity, air is saturated, air has reached its dew point
4. How does temperature affect the amount of water vapor air can hold?
Warm air can hold more water vapor than cold air.
5. What does relative humidity tell us about the air?
It tells us how close air is to be saturated or reaching 100% relative humidity or reaching dew
point. We want to know this so that we can determine if we’ll have a cloud day, rain, dew.
6. Explain 2 ways that relative humidity can be changed?
Changing air temperature (warming air = lower %, cooling air = higher %)
Changing the amount of water vapor (more = higher %, less = lower %)
7. How does a sling psychrometer work? What would happen if air were saturated? What
would happen if air were dry?
Dry-bulb measures air temperature
Wet-bulb evaporates and cools to the dew point
Bigger difference between them = lower %
Similar temperatures = higher %
If the two thermometers read the same temperature = 100% relative humidity
8. What are the 4 ways that clouds can form?
Orographic lifting- mountains, windward side = lots of clouds, leeward side = dry
Convergence- air comes together at surface
localized convective lifting- warm air rises from spots on earths surface
frontal wedging- cold air acts like a barrier pushing warm air up
rising air expands & cools due to adiabatic cooling
air must be saturated and condensation nuclei is needed for clouds to form
Water in the Air Study Guide
9. How does rain form? How does snow form?
Rain = collision-coalescence process
Snow = Bergeron process
Sleet = snow melts the freezes again ABOVE the surface
Freezing rain = snow melts then freezes ON the surface
10. What are the three main types of clouds and what do they look like?
Cirrus – high, thin, whispy
Cumulus- fluffy with flat bottom
Stratus- like a sheet covering the sky