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Flashcards in Extreme storms Deck (15)
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1
Q

Stage 1 of Hurricanes

A

tropical disturbance:
A tropical disturbance is this formation of loosely packed rain clouds forming thunderstorms. Wind circulation is very light, with meager chances to cause any amount of damage. This storm system is officially considered a tropical disturbance once it maintains its structure for more than twenty-four (24) hours. They can have sustained winds of up to twenty-three (23) miles per hour

2
Q

Stage 2 of hurricane

A

Tropical depression:
Winds become more organized, circulating in the center of the storm. A tropical depression begins to take the shape of a more significant storm; however, it doesn’t have the power necessary to take the next step and still lacks the true form

warm air is drawn into low pressure center and increases storm power

3
Q

Stage 3 of Hurricane

A

Tropical storm:
Tropical storms look like hurricanes, just smaller in size and strength. Tropical cyclones are nothing to brush off, though. These storm systems bring heavy rains, capable of causing severe flooding wherever they make landfall.
High amounts of rain, and winds have gotten to 63 km/hr

4
Q

Stage 4 of Hurricanes

A

Hurricanes:
Winds are larger 119 km/hr
warm water needs to be hotter than 26*C
Large temp gradient in the atmosphere (rapid cooling and condensation) Hurricanes
A tropical storm becomes a hurricane as soon as its wind speeds reach seventy-four (74) miles per hour. It takes the true final form of a hurricane as its eye forms completely, and its distinct parts become recognizable. Hurricanes are judged by tiers, following the Saffir-Simpson Hurricane Wind Scale (HWS).

5
Q

The pathway is determined by

A

location of formation

pre-existing atmospheric conditions

6
Q

Cyclone Hazards (3)

A

Winds, Storm surges, and Rain Fall

7
Q

How are winds a hazard

A

windspeeds are highest over where energy dissipation is highest, the storm gets energy from warm ocean water. (Windspeeds decrease rapidly overland)
Hurricanes may transition into lower energy extra tropical cyclones as they encounter land which makes blizzards and tornadoes!

8
Q

How are storm surges hazards?

A

Higher sustained wind speeds make large storm surges
can be over 3m the normal tide
associated with highest hurricane fatalities
shallow broad coastlines develop higher storm surges
normally most impactful at right quadrant of hurricane

9
Q

How is rainfall a hazard?

A

Cyclones produce 4 trillion L of water, so it causes heavy rain.
may cause flooding, eroding, and landslides
the extent of the flooding is contributed to by:
storm speeds
terrain
interaction with other weather systems
amount of water in the soil, streams, and lakes proper to the storm.

10
Q

Why has tropical cyclone movement weakened?

A

climate change has changed temperatures, lowering the force of easterlies

11
Q

Extra-tropical cyclones

A

northern pacific
large, low pressure storms
brings atmospheric rivers
50% of annual precipitation

12
Q

how do you calculate flood frequency

A

reoccurrence interval= (N+1)/(M)
where N is the number of years of the record
and M is the number of occurrences for a specific event

13
Q

mitigation for surges

A

elevated structures on pile ons

building dams and levees

14
Q

mitigation for wind

A

strengthing roofs

instaling storm shutters

15
Q

non-strucutural mitigation

A

education and better forecasting