1 / 14

Chapter 17 Section 1 What is Weather?

Chapter 17 Section 1 What is Weather?. the state of the atmosphere at a specific time and place describes air pressure, wind, temperature, and moisture in air. 1. weather. 2. How is heat given out on Earth?. - air and water currents. 3. What do heat and Earth’s air and water cause?.

gaetan
Download Presentation

Chapter 17 Section 1 What is Weather?

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 17 Section 1 What is Weather?

  2. the state of the atmosphere at a specific time and place • describes air pressure, wind, temperature, and moisture in air 1. weather 2. How is heat given out on Earth? - air and water currents 3. What do heat and Earth’s air and water cause? • weather • sun is energy that makes wind and moves weather

  3. a measure of the average amount of motion of molecules • air moving quickly = warm • air moving slowly = cold 4. temperature 5. wind • air moving in a specific direction • results from air moving from high pressure (cool) to low pressure (warm) • wind vane- arrow points in direction of wind • wind sock- sock points toward blowing wind • anemometer- measures speed with rotating cups 6. How are wind speed and direction measured?

  4. - amount of water vapor present in the air 7. humidity 8. Why can more water vapor be present in warm air than in cold air? • warm air- molecules move fast and water molecules can’t come together • cold air- molecules move slow, for liquid water and air is saturated 9. relative humidity - measure of amount of water vapor present in the air compared to the amount needed for saturation at a specific temperature

  5. temperature at which air is saturated and condensation forms • changes with amount of water vapor in the air 10. dew point pg. 473 Applying Math- Dew Point

  6. 1. How do clouds form? • by warm moist air being forced upward, expanding, and cooling • water vapor condenses into tiny droplets and remain hanging in the air 2. How are clouds classified? • by shape and height • vary with temperature, pressure, and amount of water vapor in the atmosphere • stratus • cumulus • cirrus 3. 3 main cloud types

  7. layers, smooth even sheets • form at low altitudes • fair weather, rain, or snow 4. stratus clouds • a stratus cloud • formed when air is cooled to its dew point near the ground 5. fog 6. cumulus clouds • puffy, often with flat bases • very high • fair weather or thunderstorms

  8. fibrous or curly • high, thin, feathery • made of ice crystals • fair weather, can indicate approaching storms 7. cirrus clouds • describe height of cloud base • cirro = high • alto = middle • strato= low 8. cloud prefixes • “dark rain cloud” • added to other names • ex. cumulonimbus= thunderstorm 9. What does nimbus mean?

  9. 1. Steps in cloud formation warm air is forced upward air expands and cools at higher temperature relative humidity reaches 100% water vapor condenses water droplets form a cloud

  10. 2. precipitation - water falling from clouds 3. What factors affect the size of raindrops? • strong updrafts in a cloud = large drops • rate of evaporation = dry, may never reach Earth 4. 4 main types of precipitation • rain - sleet • snow - hail

  11. 5. What determines the type of precipitation? • air temperature 6. rain • water droplets fall from the sky • temperatures are above freezing (32°F or 0°C)

  12. water vapor changes directly into a solid in the atmosphere (sublimation) • 32°F or 0°C or below for snow 7. snow

  13. 8. sleet -rain passes through a layer of freezing air near Earth’s surface

  14. lumps of ice • forms in cumulonimbus clouds • water freezes in layers around nucleus of ice • usually smaller than 2.5 cm, can be size of softballs 9. hail

More Related