Hurricanes

Front 1

What is a hurricane?

Back 1

A large tropical cyclone in which heat energies convert the heat energy of the tropical ocean into winds and waves.

Front 2

How are hurricanes named?

Back 2

They are the only natural disasters given human names.

Front 3

What are three characteristics of hurricanes?

Back 3

1) Winds over 150 mph
2) Can temporalily raise sea level 20ft from surges
3) Heavy rains can cause flooding.

Front 4

Where do hurricanes come from?

Back 4

Across the ocean, primarily starting in Africa.

Front 5

How does a hurricane develop?

Back 5

1) Tropical Disturbance-low pressure zone draws in thunderstorms with weak surface winds
2) Tropical Depression-surface winds become stronger and flow more efficently around the storm
3) Central core acts like a chimney, sending warm moist air up to the stratosphere, rising air cools, reaches its dew point, water vapor condenses and latent heat is released
4) Heat surrounds air causing stronger updrafts which increase the rate of inflow
5) Tropical Storm- converging winds continue to spiral upward winds increase to over 40 mph
6) Hurricane- winds are consistently above 74 mph
6)

Front 6

When is a hurricane given a name?

Back 6

When the storm become a tropical depression

Front 7

What are the requirements for a hurricane?

Back 7

1) Seawater should be at least 80F in the upper 200ft of the ocean
2) Atmosphere must cool fast enough with height to make it unstable
3) Mid-troposphere must contain enought moisture to sustain thunderstoms
4) Must occur at least 500 km from the equator, coriolis force must be present so that low pressure can be maintained
5) Must be pre-exisiting near-surface convergence of rotating moist air
6) Upper-level winds should be weak and blowing in the same direction the storm is moving

Front 8

What is a hurricane called in other parts of the world?

Back 8

Cyclones in the Indian Ocean, Typhoons in the Pacific Ocean and Hurricanes in the Atlantic Ocean

Front 9

Explain storm movement

Back 9

Increasing winds blow faster at the center, the eye is calm and inside the eye cold air descends and it absorbs moisture and leaves the eye cloud free and clear.

Front 10

Which side of the hurricane is more dangerous?

Back 10

The right side because winds are always stronger on the right side of a moving hurricane in the northern hemisphere.

Front 11

What is the Saffir-Simpson Scale?

Back 11

The hurricane intensity scale which indicates barometric pressure, wind speed, storm surge and the level of damage.

Front 12

Where do hurricanes mostly occur?

Back 12

In the Atlantic in the months of August, September and October

Front 13

How does the Bermuda high steer a hurricane?

Back 13

Off the east coast of the US semi-permanent high pressures and other high pressures moves eastward off North American and the hurricane gets steered between low pressure and troughs

Front 14

What causes a hurricane to change its track?

Back 14

Interaction with the land, large scale air masses moving in erratic paths, and upper level winds

Front 15

What is a storm surge?

Back 15

Rise in sea level before and in the eye of
a hurricane, like a big wave, devastates the coast

Front 16

How are storm surges produced?

Back 16

Sea level rises due to the low pressure under the eye, asa the water gets pushed unto the shallow zone along the coast sea level rises.

Front 17

Where are storm surges produced?

Back 17

In the eye of the hurricane

Front 18

Why are barrier islands not safe?

Back 18

Flooding can destroy roads and bridges, Flood surges can push water onto the land, and ebb surge can produce a retreating surge

Front 19

How does damage occur?

Back 19

It is related to the intensity and duration of the storm as well as the angle at which it approaches land and the population density

Front 20

How is damage reduced?

Back 20

Warning and evacuation through hurricane watches and warnings, maintaining beach width and dune height, engineering solutions such as floodwalls or movable gate series, enforcement of construction codes and zoning/land use by limiting coastal areas to recreational purposes.