Presentation on theme: "AIM: Types of severe storms Do Now: In your notes answer the following question. 1) Which pressure system is the cause of severe weather, what is another."— Presentation transcript:
AIM: Types of severe storms Do Now: In your notes answer the following question. 1) Which pressure system is the cause of severe weather, what is another name for this type of pressure?
caused by intense low pressure -rotate Counterclockwise -pull air in towards the center. I. Severe Storms (Cyclones)
A. Thunderstorms - caused by moist, warm (mT) air rising quickly (cold front). 1) Nor'easters are massive cyclones that make land fall in the North East due to winds blowing from the NE. Cumulonimbus clouds (takes on an anvil shape)
- lightning heats the air making it expand. The air collapses back on itself creating thunder. 2) Thunder and Lightning - Friction between raindrops and the cloud builds an electric charge causing lightning.
B. Tornado (Spring Early Summer) 1.Most powerful storms on Earth. - in contact with both a cumulonimbus cloud and the surface of the earth. - they occur when a cold air mass (cP) meets a warm air mass (mT). Winds can exceed 300 mph!
The mid-west region where tornados occur in great numbers is called “Tornado Alley”.
2. Strength is measured with the fujita scale, which measures wind speeds and destruction.
II. El Nino Conditions: seasonal shift in global weather patterns (about every 5 years) causes changes in precipitation, winds and sea levels along pacific coasts.
III. Monsoons Large seasonal changes in winds due to the differences in specific heat of land and water. Mostly seen in the Indian Ocean. - In winter, the water is warmer than the land causing a land-breeze to occur, pushing storms out into the ocean creating period of drought. - Summer temperatures cause the land to heat up faster than the water causing a sea-breeze to occur, pushing storms onto the land creating floods.