This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Chapter 5 Review Questions Explain how dew, frozen dew, and visible frost each forms. Dew forms when water condenses on objects near the ground when their temperatures have fallen below the dew point. Frozen dew forms when the air temperature drops to freezing or below and then the dew freezes becoming tiny beads of ice. Visible white frost forms on cold, clear, calm mornings when the dew-point temperature is at or below freezing. When air temperatures cools to the dew point (now called the frost point) and further cooling occurs, water vapor can change directly to ice without becoming a liquid first, this is process is known as deposition, and forms a delicate white crystals of ice known as hoarfrost, white frost, or frost. Distinguish among dry haze, wet haze, and fog. Dry haze is particles that are very small, fine, dry dust particles or salt particles dispersed through a portion of the atmosphere. Individually, these are not visible but cumulatively they will diminish visibility. Wet haze are these same particle but are wet and larger in size. Fog is a cloud with its base at the earths surface. Why is fog that forms in industrial areas normally thick? Dirty city air with its abundance of nuclei produces many tiny fog droplets, which greatly increases the thickness (opaqueness) of the fog and reduces visibly. The fog that forms over oceans has smaller number of condensation nuclei (Condensation nuclei are tiny particles upon whose surfaces condensation of water vapor begins in the atmosphere. Condensation nuclei are extremely light and can remain in the air for many days. Nuclei are most abundant over cities where polluted air may contain nearly 1 million particles per cubic centimeter. The particles decrease in cleaner air and over the oceans) and produce fewer but larger fog droplets. How can fog form when the airs relative humidity is less than 100%? Fog can form at relative humidity that is as low as 75 percent because the continuous condensation process. This process beings when the water vapor condenses onto on to hygroscopic (the ability of a substance to attract and hold water molecules from the surrounding environment through either absorption or adsorption with the adsorbing or absorbing material becoming physically 'changed,' somewhat: by an increase in volume, stickiness, or other physical characteristic of the material as water molecules become 'suspended' between the material's molecules in the process) nuclei. Name four types of fog. (a) What conditions are necessary for the formation of radiation fog? (b) Here is all of them: Radiation Fog or ground fog - forms at night under clear skies with calm winds, when a shallow layer of moist air near the ground is overlain by drier air. Since the moist layer is shallow it does not absorb much of the outgoing infrared radiation. As the earths surface continues to cool, provided a deep enough layer of moist air is present near the ground, the humidity will reach 100% and fog will form. Radiation fog varies in depth from 3 feet to about 1,000 feet and is always found at ground level reach 100% and fog will form....
View Full Document
This note was uploaded on 09/10/2011 for the course GO 101 taught by Professor Loving during the Spring '10 term at Park.
- Spring '10