Download
water and weather n.
Skip this Video
Loading SlideShow in 5 Seconds..
Water and Weather PowerPoint Presentation
Download Presentation
Water and Weather

Water and Weather

113 Views Download Presentation
Download Presentation

Water and Weather

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Water and Weather

  2. Weather and Water • Most weather we pay attention to involves water http://img.dailymail.co.uk/i/pix/2008/04_01/tornadoDM3030a_800x533.jpg http://blogs.reuters.com/wp-content/uploads/2007/07/storm1.jpg http://img.dailymail.co.uk/i/pix/2008/04_01/tornadoDM3030d_468x312.jpg

  3. Important Terms • Humidity – amount of water vapor in the air • Relative Humidity - ratio of water vapor in an area relative to how much it can hold • warm air can hold more water than cold air before becoming saturated – can hold no more water vapor • (pressure also a factor) • Expressed as a % • Does not tell you actual quantity of water vapor in air http://wpcontent.answers.com/wikipedia/en/4/41/Relative_Humidity.png

  4. Important Terms http://fuffer.files.wordpress.com/2008/03/humidity-smaller.jpg

  5. Important Terms • Dew Point – temperature air must be cooled at to reach saturation (100% relative humidity) • High dew point temps = moist air • Low dew point temps = dry air • At the dew point water vapor can condense • at night low temps near ground cause water vapor to condense  dew/fog • very cold temps near ground cause water vapor to freeze and fall out  frost • during the day, as warm air rises, it cools and often becomes saturated  clouds

  6. Dew Point Mean daily average dew point temperature in October http://www.climatesource.com/us/fact_sheets/td_us.gif

  7. Cloud Formation • Clouds form as warm, moist air rises, expands, and cools • As air cools, it can hold less water – relative humidity increases • When air reaches dew point (100% relative humidity), the water condenses (goes from gas to liquid) around a piece of dust, sea salt, or other particle (condensation nuclei) • When millions of water droplets collect, cloud is formed http://www.cmmap.org/images/learn/clouds/sfcHeat.jpg

  8. Cloud Formation http://www.vivoscuola.it/US/RSIGPP3202/umidita/lezioni/formation2.GIF http://www.weatherquestions.com/Cloud_formation_convective.gif

  9. Cloud Formation • May also form when wind hits a mountain and has nowhere to go but up  air rises, expands, and cools • Can also form when air masses of different temps collide  warmer air is forced up above cool air mass where it expands and cools http://www.cmmap.org/images/learn/clouds/risingAir.jpg

  10. Cloud Formation • Types of cloud form: • at different altitudes • High • Middle • Low • into different shapes • Cirrus • Cumulus • Stratus • Make Clouds lab • Build Cloud Spotters • Monitor clouds for 1 week http://marktwainmediascience.com/CD-410015.jpg

  11. Precipitation • Cloud droplets collide and combine into bigger droplets (coalescence) • When droplets are too heavy, they fall (precipitation) • May fall as liquid or solid or something in between (rain, snow, sleet, hail) http://www.mmm.ucar.edu/research_mmm/processes/images/ice_illustration.png

  12. Precipitation • How does water get in the air in the first place? • Evaporation radiation heats up water and causes phase change • Warm surface water (oceans) evaporates faster than cold http://www.cotf.edu/ete/images/modules/msese/earthsysflr/EFCycleP3.gif