Why is the moist adiabatic lapse rate lower than the dry-adiabatic lapse rate?

1. Chapter 18 Test Review Guide • Why is the moist adiabatic lapse rate lower than the dry-adiabatic lapse rate? • Heat is released during condensation. • When temperatures are below freezing, which would grow faster? Ice crystals or supercooled water droplets? • Ice crystals • 3. What type of weather is found in areas of rising air? • Rainy • 4. How is the amount of snowfall measured? • Using a measuring stick in an open field.

2. 5. How does frost kill plants? Cells freeze and burst. 6. Why does hot water evaporate faster than cold water? There are more molecules with enough energy to leave the water’s surface. 7. Why does air temperature rarely fall below the dew point? Condensation slows cooling. 8. Which is higher, the wet-bulb or dry-bulb readings? Dry-bulb readings. 9. When do stratiform clouds usually form? When air is stable. 10. In which layer of the atmosphere is water vapor usually found? Troposphere

3. 11. Would you find more rainfall in high or low pressure areas? Low 12. Can weather modification methods work on a clear day? No, clouds are needed. 13. What is dew point? Temperature at which the air is saturated with water vapor. 14. How do you determine relative humidity? Amount of Water Vapor in Air x 100 Saturation Point OR Specific Humidity x 100 Capacity

4. 15. What happens to the energy (absorbed or given off) and the temperature of water during evaporation? Energy is absorbed and temperature is cooled. 16. During what time of year would you find the most stratocumulus clouds? Winter 17. Which holds more water – warm or cool air? Warm 18. What is supersaturated air? Cooled below dew point and no condensation nuclei. 19. How is ground fog produced? Radiation 20. Cumuliform clouds occur when . . . Air movement is vertical.

5. 21. Describe a cloud which is surrounded by unstable air. The cloud is warmer and more buoyant than surrounding air. 22. When do thunderstorms form? When there is a deep layer of unstable air. 23. What is the temperature in the flat, anvil-shaped top of a cumulonimbus cloud? It is equal to the temperature of the surrounding air. 24. How are layered clouds formed? By horizontal air movement. 25. How do raindrops formed by the warm-cloud process enlarge? They collide and join with other droplets.

6. 26. What determines the size of raindrops? The type of nuclei, height of clouds, and amount of evaporation. 27. Which cloud type produces hail? Cumulonimbus 28. List several chemicals used for weather modification? Solid CO2, lead iodide, silver iodide. 29. What contributes to the production of acid rain? Car exhaust, burning of fossil fuels, and volcanic eruptions. 30. List several environmental effects related to acid rain. Fish kills, damaged plants, and acidic soil.

7. 32. What are condensation nuclei? Particles around which water vapor condenses. 33. What is a hygrometer? An instrument used to measure humidity. 34. On the average 10 inches of snow equals one inch of rain. 35. A parcel of air at sea level is saturated and has a temperature of 14 ºC. What will the temperature be if it rises 400 meters? 11.6 ºC Moist adiabatic lapse rate = 0.6 ºC per 100 meters 14.0 ºC – 0.6 – 0.6 – 0.6 – 0.6 = 11.6 ºC 100 m 200m 300m 400m

8. 36. A parcel of dry air at sea level has a temperature of 21 º C. What will the temperature be if it rises 400 meters? 17 º C Dry-adiabatic lapse rate = 1 º C per 100 meters 21 º C - 1 º C -1 º C -1 º C -1 º C=17 º C 100 m 200m 300m 400m 37.Over what type of area would the flat bases of cumulus clouds be highest? Where surface temperature and dew point varies the most. 38. What does lifting condensation level mean? Point where the flat base of a cloud forms. Point where temperature equals dew point. Point where water vapor condenses.