EES Exam 2 Hurricanes

What is a hurricane and how is it related to a tropical cyclone?

A hurricane is a tropical cyclone. Circulating weather systems that form over tropical-subtropical water. 

What are tropical depressions and storms?

Tropical depression: thunderstorms circulating around low P, appears unorganized,

<39 mph. Tropical Storm: Organized, rotation more obvious, sustained winds 39-74 mph, gets a name

How do hurricanes form? What conditions encourage them to form and strengthen?

80+ water to a depth of 150ft, cool/moist air with height so thunderstorms can develop, light winds at height, tropical distribution with inflow towards low pressure, some rotation. Rarely form over water <80F and will weaken over cold water and  land

What controls the spin direction of hurricanes and influences their paths?

The Coriolis effect: 

In the Northern hemisphere hurricanes spin counterclockwise

In the Southern hemisphere hurricanes spin clockwise 

Where do North Atlantic hurricanes form? When is hurricane season in the northern hemisphere and why?

Cape Verde hurricanes, gulf of Mexico, Caribbean. Go east to north

Form in ocean, weaken over land. Hurricane season here is 97% between June 1 and Nov 30 because the temperature of the ocean is highest 

What kind of damaging effects can hurricanes have on people?

Stormsurge- floods, coastal erosion

Heavy rain- triggers floods, mass movement (landslides)

High winds- wind damage to structure

How does storm surge form? How does the profile of the shore influence damage by storm surge?

Surface winds above the ocean's surface pushes water f toward hurricanes eye, creating a mound of water. As water approaches it piles up causing storm surge.

Why is the storm surge worse on the eastern side of a hurricane in the northern hemisphere?

The northern hem is flatter

Why did hurricane Katrina cause so much death and destruction in New Orleans?

Storm surge in the northern hemisphere is worse on the eastern side of the hurricane due to the direction of the hurricanes spin

80% of New Orleans ended up underwater and 1,836 people died due to storm surge.

Flooding happened because of damage to levies

In a river flood plain, but protected by several levees for several hundred years

Lack of preparedness

Why is New Orleans below sea level?

On a river delta, has lakes around it, has ocean around it.

How did hurricane Helene do so much damage in North Carolina?

Extensive flooding, landslides, debris flows, 

What are some ways to mitigate hurricane damage? Can hurricanes be predicted?

Land-use planning, insurance and other regulations for safety measures, evacuation, disaster awareness and preparedness, reactive response (after a hazardous event), forecast, prediction, warning

How can dams be used to control flooding?

Block water from certain areas

How are spillways used?

allow excess water to be drained

What are some adverse impacts opening spillways may have?

May harm some communities by flooding them, to save others

What are some problems that building levees may cause?

Levees raise the bank level along a stream channel which can cause higher discharge downstream and from upstream which can cause flooding on both ends

What is a floodwall?

Wall that protects from flooding, good but expensive.

How is channelization used to prevent flooding? What problems can channelization cause?

Straightens, deepens, widens & or lines a river with concrete

How can zoning be used to prevent possible future flood damage?

Regulating development, and allowing river to flood areas