Chapter 5 Questions For Thought
Chapter 5 Questions for Thought
1. Explain the reasoning behind the wintertime expression, “Clear moon, frost soon”? On clear, calm nights, objects and the earth surface cools off by emitting infrared radiation. This cooling effect is more rapid on clear night than cloudy nights since there is no clouds to emit back to the surface. Hence the phrase “clear moon, frost soon”. The cool surface is then mixed with air above it, which will eventually cool to the dew point and water vapor will appear on the cooled surfaces. If the temperature continues to fall in the freezing range then the dew will freeze and frost will form.
2. Explain why icebergs are frequently surrounded by fog? Fog surround icebergs due to advection fog. This type of fog is caused by the iceberg surface temperature being colder than the moist ocean air moving over the iceberg. As the warmer air moves over the iceberg heat transfer by conduction occurs and the air is cooled to its saturation point eventually forming fog.
3. During a summer visit to New Orleans, you stay in an air-conditioned motel. One afternoon, you put on your sunglasses, step outside, and within no time your glasses are “fogged up”. Explain what has apparently caused this? New Orleans is a humid location and averages a dew point temperature of 72F degrees and contains a lot of water vapor. The air-conditioned room cools your glasses down near or below the outside dew point temperature. As you step outside into the humid, warm and moist air, water vapors condenses onto the glasses forming fog.
4. While driving from cold area (well below freezing), frost forms on the windshield of the car. Does the frost form on the inside or outside of the windshield? How can the frost form when the air is so warm? When driving through the cold area the outside of the window will cool to below freezing. When the windshield is exposed to warm air, it is chilled to saturation point and produces frost through deposition pg116
1. Explain the reasoning behind the wintertime expression, “Clear moon, frost soon”? On clear, calm nights, objects and the earth surface cools off by emitting infrared radiation. This cooling effect is more rapid on clear night than cloudy nights since there is no clouds to emit back to the surface. Hence the phrase “clear moon, frost soon”. The cool surface is then mixed with air above it, which will eventually cool to the dew point and water vapor will appear on the cooled surfaces. If the temperature continues to fall in the freezing range then the dew will freeze and frost will form.
2. Explain why icebergs are frequently surrounded by fog? Fog surround icebergs due to advection fog. This type of fog is caused by the iceberg surface temperature being colder than the moist ocean air moving over the iceberg. As the warmer air moves over the iceberg heat transfer by conduction occurs and the air is cooled to its saturation point eventually forming fog.
3. During a summer visit to New Orleans, you stay in an air-conditioned motel. One afternoon, you put on your sunglasses, step outside, and within no time your glasses are “fogged up”. Explain what has apparently caused this? New Orleans is a humid location and averages a dew point temperature of 72F degrees and contains a lot of water vapor. The air-conditioned room cools your glasses down near or below the outside dew point temperature. As you step outside into the humid, warm and moist air, water vapors condenses onto the glasses forming fog.
4. While driving from cold area (well below freezing), frost forms on the windshield of the car. Does the frost form on the inside or outside of the windshield? How can the frost form when the air is so warm? When driving through the cold area the outside of the window will cool to below freezing. When the windshield is exposed to warm air, it is chilled to saturation point and produces frost through deposition pg116