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Weather. SCOTT HANDEL National Oceanic and Atmospheric Administration. Photo: Courtesy NOAA. Outline. Thunderstorms Hail/Lightning Tornadoes Tsunamis Hurricanes (Time Permitting). Thunderstorm Formation. Lightning. How Lightning Forms.
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Weather SCOTT HANDEL National Oceanic and Atmospheric Administration Photo: Courtesy NOAA
Outline • Thunderstorms • Hail/Lightning • Tornadoes • Tsunamis • Hurricanes (Time Permitting)
How Lightning Forms The connection is made and the protons rush up to meet the electrons. It is at that point that we see lightning and hear thunder. A bolt of lightning heats the air along its path causing it to expand rapidly. Thunder is the sound caused by rapidly expanding air.
http://www.archive.org/details/Dupa5gdr-BelizeCrawlerLightningStorm697-3http://www.archive.org/details/Dupa5gdr-BelizeCrawlerLightningStorm697-3
How does Hail Form? Strong updrafts of warm air and down-drafts of cold air are in a thunderstorm. If a water droplet is picked up by the updrafts...it can be carried well above the freezing level. With temperatures below 32°F...our water droplet freezes. As the frozen droplet begins to fall...carried by cold downdrafts...it may thaw as it moves into warmer air toward the bottom of the thunderstorm But...it may also get picked up again by another updraft...carrying it back into very cold air and re-freezing it. With each trip above and below the freezing level our frozen droplet adds another layer of ice. Finally...our frozen water droplet...with many layers of ice - much like the rings in a tree...falls to the ground - as hail!
Tornadoes What is a tornado? "a violently rotating column of air, pendant from a cumuliform cloud or underneath a cumuliform cloud, and often (but not always) visible as a funnel cloud."
http://www.archive.org/details/AH-Tsunamis_-_Know_What_to_Do
HURRICANES!…An overview of tropical cyclones Princeton University Quest Science Workshop July, 2007
Why are the winds so strong in a hurricane? Winds always move from areas of higher pressure to areas of lower pressure. The bigger the difference between the high and low pressure, the stronger the winds. H L The winds from Hurricane Fabian battering Bermuda on September 5, 2003.
What causes the winds to rotate around a hurricane? H H L H H The Coriolis Effect: A change in the direction of moving objects due to those objects moving on a rotating, spherical planet. Hurricane Isabel making landfall on September 18,2003