13.1 notes Thunderstorms
• Extreme weather is controlled by the same processes as good weather.
Main idea
• Moisture in low-mid levels of atmosphere
• A lifting force to cause air to begin rising; such as heated air near the ground!
• Unstable air (air that will continue rising & rising!!)
Atmospheric conditions required
Thunderstorms
• LightingDevelopment: a buildup of charges forms as tops of clouds become +++ charged & bottoms of clouds become ---- charged.
Components of thunderstorm
• Thunder Development: Lighting quickly heats the air around it, causesrapid expansion & a “boom” sound.
Describe:A violently rotating column of air rising up into a cloud & also touchingthe ground below.
Tornadoes
Extreme weather produced by thunderstorms
Tornadoes Conditions required:• Wind Shear: a change in speed &
direction at differ altitudes: causes clouds to spin.
• Sinking air pushes one end of column towards land. Other end rises: spins faster!!
• Spinning cloud joins & creates a funnel cloud.
• When funnel cloud touches ground, it creates a tornado!!!!!!!!!!!!
Describe: low-pressure weather systems w/ circular wind motion; rotates counter-clockwise in N. Hemisphere.
Tropical Cyclones
“Eye am watching you!”
Explain names:
TYPHOON: when thunderstorms converge in the W. Pacific or Coast off of China.
Philippines
HURRICANE: when storms are born off of the coast of Africa & travel across the Atlantic Ocean.
Conditions Required: • Growth is over warm ocean waters !
• Air spins & rises, then it cools & causes it to release heat
• When wind reaches 74+mph: called a hurricane!!
Describe: Winter storms that bring lower temps, high winds, heavy snow, & poor visibility.(Alaska! Need I say more!)
Other extreme weather: blizzards
“You are a crazy old man”