Hurricanes, Tornadoes etc.

Tornadoes Features: Violent windstorm Rotating column of air that extends down from a cumulonimbus cloud Low pressure insides cause the air to rush into the tornado Winds approach 300 mph Smaller suction vortices from inside stronger tornadoes Occurrence and Development Most frequent from April and June Associated with severe thunderstorms Exact cause of tornadoes formation is not known Associated with huge thunderstorms called supercells Supercell: a thunderstorm with a deep rotating updraft Element of rotation Some produce tornadoes, some do not Occur most often along cold front Most occur during summer months Squall line No strict size Range 40-1000 km long Composed of convective cells behind the leading edge of a system Sometimes includes supercell Characteristics Diameter between 500-2000 feet Speed across landscape about 30 mph Cut about 6-mile path long Maximum winds range beyond 310 mph Destruction Depends on strength of winds Most injuries and deaths from flying debris Fewer than 2% of US tornadoes result in deaths Forecasting Difficult to forecast because of their small size Watch To alert the public to the possibility of tornadoes Issued when the conditions are favorable Covers 25,000 square miles Tornado warning is issued when tornado is sighted or indicated by weather radar Use of Doppler radar helps increase REVIEW Earth System: 4 major subsystem Atmosphere: air Biosphere: living things Hydrosphere: all types of water Geosphere (lithosphere): earth underneath us Geography: the study of the Earth’s surface and the processes that affect it Cultural/Human Geography Natural Geography Technical Geography Know big hurricane and numbers and years associated with them Characteristics of air masses: Temperature Moisture (humid) Pressure Maritime: moist Polar/artic: cold Continental: dry tropical/equatorial: warm Warm front: warm(er) to the relative to the air it’s replacing Cold front: most likely to have storm front Front: place where 2 air masses meet Stationary front: where 2 unlike air masses meet but don’t displaces each other Occluded front: Cold air, warm air, cold air- cold air catches up with other cold air and causes Midlatitude cyclone Low pressure: clouds (converging ascending) Cyclonic movement High pressure: clear (diverging descending) Anticyclonic