CRCT Question

1. CRCT Question Which type of cloud indicates fair weather? Stratus Cumulus Cirrus Stratus nimbus

2. Think, Pair, Share What do you know about clouds?!?!

3. Water in the Air • Water gets into the atmosphere through evaporation. • Called humidity • Causes clouds • Changes density of the air • Dew Point – temperature at which condensation occurs. Depends on the humidity and air temperature. • Clouds form at whatever elevation dew point is reached • Rain shadow – caused when water vapor hits mountains, gets pushed upward, cools off, condenses, and drops it water vapor load – all on the windward side of the mountain.

4. Humidity Is a measure of how much water vapor is in the air. It is measured in a percent using a psychrometer. More humidity means more clouds and more likely chance of precipitation.

5. Dew point is the temperature when water vapor condenses to a solid or liquid This forms clouds!

6. Clouds form when the water vapor reaches the dew point. Remember that as you go up in the troposphere, the temperature decreases. Dew point http://www.wildlandschool.net

7. This is the reason clouds look to be about the same height in the sky and flat on the bottom. They are! Dew point temperature is reached.

8. Types of Clouds • Cumulus – cotton balls – indicates fair weather • Stratus – flat layers – often has precipitation • Cirrus – high, thin clouds – usually means change in weather • Fog – cloud on the ground

9. Let’s Take a Closer Look!

10. Cirrus – highest type of cloud. Due to elevation, made of ice crystals. They indicate that a change in the weather is coming.

11. Cumulus – round, puffy clouds Indicate fair weather

12. They can build up to form storm clouds that contain hail, lightning, and tornadoes.

13. http://www.colby.edu/ Cumulonimbus clouds often produce bad weather (lightning and hail) Nimbus/nimbo means rain. Notice that it is getting flat on the top. That means the top of the cloud has reached the top of the troposphere and cannot go any higher.

14. Cumulonimbus

15. Stratus – flat layer of clouds. Often have rain.

16. Nimbostratus clouds often produce rain for many hours. Like stratus clouds, they cover the sky. The only difference is that these are producing rain or snow.

17. Other cloud types

18. If the dew point temperature is the same as the air temperature on the ground, fog forms! The cloud actually forms on the ground.

19. Precipitation –cloud droplets get too heavy to stay in the cloud • Kinds of precipitation • Rain • Sleet • Hail • Snow • Measured with a rain gauge or ruler

20. What is the difference between rain and mist?!

21. The most common form of precipitation is rain. The term rain is restricted to drops of water that fall from a cloud and have a diameter of at least 0.5 millimeter. Drizzle and mist have smaller droplets.

22. As water vapor collects into larger and larger droplets, gravity will cause them to fall to the ground as rain, sleet, hail, or snow.

23. Droplets come in many sizes raindrop Drizzle droplet Mistdroplet Cloud droplet