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Flashcards in tropical cyclones Deck (21)
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1
Q

what are hurricanes?

A

intense low pressure systems that develop in the tropics

2
Q

what is the diameter?

A

200-700km

3
Q

how are they caused?

A

an area of low pressure is created through rising water of ocean and sinking cold air, warm air is drawn in a spiralling manner, enlarging into tropical depressions that spin at a much intense rate

4
Q

what temp does the ocean have to be?

A

27c

5
Q

how deep does the ocean have to be?

A

at least 70m

6
Q

how far from the equator do they develop?

A

5-20 degrees north or south

7
Q

why can they not develop at the equator?

A

the Coriolis force is weaker at the equator and will stop the circular air flow from developing

8
Q

what is used as energy?

A

latent heat and moisture

9
Q

what is the diameter of the centre eye?

A

10-15km

10
Q

what is it like in the eye?

A

there are calm conditions, clear skies and higher temperatures

11
Q

how fast does win move around the eye?

A

300km an hour

12
Q

how is a cyclone stopped?

A

when it runs out of latent heat and moisture, for example travelling across land

13
Q

wich direction do they tend to move?

A

westwards

14
Q

what percent of hurricanes do the Caribbean and gulf of Mexico get a year?

A

11%

15
Q

who long do they normally last?

A

7-14 days

16
Q

what scale is used to measure them?

A

saffir simpson scale

17
Q

how fast do the winds have to be to reach a category 5 hurricane?

A

250km

18
Q

what is a storm surge?

A

a rapid rise in sea level when water is piled up against a coastline to a level afar in excess of the normal conditions at high tide

19
Q

how are storm surges linked to hurricanes?

A

normally created

20
Q

what are the impacts of hurricanes?

A
  • high winds (250km)
  • heavy rainfall (200-300mm)
  • storm surges
21
Q

what is the ITCZ>

A

point on earth where trade winds meet as they meet a belt of low pressure forms