Hurricanes and Tornadoes Lecture Notes

Flashcards about Hurricanes and Tornadoes

Hurricanes

Atmospheric motions on a rotating Earth. Powered by specific conditions required for their generation and cause storm surges.

Coriolis Effect

Deflects winds due to the Earth's rotation, influencing the direction of hurricane spin.

Pressure Gradient Force (PGF)

Force that drives winds from high to low pressure areas.

Development of the Eye

Air descends within the eye, preventing clouds from forming because the air warms as it sinks.

Hurricane Conditions

Requires seawater > 27°C (80°F), warm moist air, weak upper winds and coriolis force.

Latent Heat Release

Warms the air and causes the air to rise higher

Tropical Depression

Becomes 'Tropical storm' when wind speeds exceed 39 mph.

Tropical Storm

Becomes 'hurricane' when wind speeds exceed 74 mph

Storm Surge

Most hurricane deaths result from this.

Katrina Disaster

Hurricane Katrina caused $120 billion in damages, and the responsibility for the flooding was laid squarely on the Army Corps in 2008

Thames Barrier

Located in London at ~$20,000 per closure; might last until 2060, 2070.

Bangladesh Vulnerability

35% of Bangladesh is <6 m above sea level, and the population expects to double in 30 years.

Tornado conditions in the U.S.

Low altitude, humid air from the Gulf of Mexico meets middle-altitude, cold dry air from Canada, spinned up by powerful jet stream winds

Main characteristic of Tornadoes in the U.S.

Often occur at trailing end of super-cell thunderstorms

Tornadoes vs. Hurricanes

Hurricanes are powered by heat, die out on land, favored by weak winds, are long-lived, and spin c-clockwise. Tornadoes are powered by jet stream, latent heat, lightning, almost exclusively on land, need strong winds, are short-lived and spin c-clockwise.