1. Study Guide Test 12/8 Topics Include: Relative Humidity Dew Point Cloud Formation Air Masses Fronts Scientific Method

2. Make Sure You Understand: Relative humidity is the amount of moisture (water vapor) in the air compared to the amount of moisture the air can hold at that temperature. Dew Point is when air cools to the temperature at which air is saturated. Assuming the amount of water vapor in the air stays the same… If the temperature increases, then the relative humidity decreases. If the temperature decreases, then the relative humidity increases.

3. What is a cloud made of? A cloud is made of water droplets condensed on dust particles in the air Dust Particle Water Vapor

4. Be able to answer the following: If you see these clouds in the sky what weather can you expect? Name of CloudAppearanceEffect 1. Cumulus White, puffy, cotton ball clouds Fair weather. Nice day outside. 2. Cirrus Feathery, wispy clouds. Made of ice crystals! Fair at present, BUT rain in 24 – 48 hours (a day or two). Warns of a warm front approaching. 3. Stratus Flat layers of gray cloudsBrings gentle steady rain. Forms in a warm front. 4. Cumulonimbus Thunderhead! Dark flat bottoms building into anvil shaped tops Thunderstorms! Heavy rain, thunder, lightning, and possible hail. Forms in cold front.

6. Air Masses A. mP B. cP and/or cA C. mP D. cT E. mT F. mT G. What is the origin of each of the 3 mT air masses? The Pacific Ocean, the Gulf of Mexico, and the Atlantic Ocean

7. Air Masses An air mass is named for it’s temperature and moisture level. When two air masses meet the warm air mass will rise and the cool air mass will sink. Continental Maritime Polar Tropical Dry Wet Cold Warm

9. Cold Air Masses A Continental Polar (cP) air mass brings cool, dry weather in the summer. A Continental Polar (cP) air mass brings extremely cold weather in the winter. A Maritime Polar (mP) air mass brings cool, foggy weather in the summer. A Maritime Polar (mP) air mass brings cool weather with rain and snow in the winter.

10. Warm Air Masses A Continental Tropical (cT) air mass brings clear, dry, and hot weather in the summer. A Continental Tropical (cT) air mass brings warm and dry weather in the winter. A Maritime Tropical (mT) air mass brings hot, humid weather, with possible hurricanes and thunderstorms in the summer. A Maritime Tropical (mT) air mass brings mild, often cloudy weather in the winter.

11. Fronts Fronts are the boundary between different air masses. Cold fronts create short, heavy, violent periods of rain followed by cool fair weather Warm fronts occur when warm air rises and condenses into long areas of clouds which bring gentle rain or snow followed by warmer weather Stationary fronts create clouds and fog at the site of the front and can bring days of rain or snow Occluded fronts occur when warm air is cut off from the ground which can bring heavy wind and precipitation

12. Warm front (red) Make sure you know: 1. Which symbol belongs to which front. 2. The color of each front symbol. 3. The type of weather does each front bring. Occluded front (purple) Cold front (blue) Stationary front (red and blue)

13. Think about it… Would a farmer prefer the rain from a warm front or a cold front to come through his area during the growing season? Explain why.. Suppose you are planning an outdoor activity for tomorrow afternoon. You hear on the weather that a front is coming through tonight. With the understanding that you want to be outside tomorrow, which of the 4 fronts we learned about would you rather have come through? Fully explain why.

14. A Farmer Would Prefer A.. WARM FRONT! because… Warm Fronts are good for farmers because… Gentle, prolonged rain that can soak in soil and water plants It will NOT erode the soil It will NOT damage plants It is warm after the front Cold Fronts are bad for farmers because… Short, violent rain that may not soak into the soil to water plants Violent rain that erodes soil It will damage plants (hail) It is cold after that front, which may kill the plants

15. Scientific Method (know them in order) The Steps of the Scientific Method: People In Hawaii Eat Coconuts! Problem Information Hypothesis Experiment Conclusion During the experiment you must remember: Madison Police Department! Materials Procedures Data