Tropical Storms Flashcards
when do tropical storms develop
- when the sea temperature is 27C or higher
- and the wind shear between higher and lower parts of the atmosphere is low
what is wind shear
the differences in wind speed
what happens when the sea is heated to temperatures of 27C and above
- the warm moist are rises and condensation occurs
- this releases huge amounts of energy which makes the storm powerful
what does the rising air from the high sea temperatures cause
- low pressure
- which increases surface winds
why do tropical storms move towards the west
because of the easterly winds near the equator
why do tropical storms spin
because the earths rotation deflects the paths of the winds
why do storms get stronger above water but weaker above land
- above water they get stronger due to the energy from the warm water
- which causes wind speeds to increase
- but above land they lose strength
- because the energy supply from the warm water of the sea is cut off
why do most tropical storms only occur 5 to 30 degrees north and south of the equator
- because this is where the temperatures of the seas are highest
- any further from the equator and the water wouldnt be warm enough to provide the energy for the storm
when are sea temperatures highest in the northern hemisphere, especially over the pacific
in late summer and autumn
what are the main properties of a tropical storm
- they are circular in shape
- hundreds of kilometres wide
- usually last 7 to 14 days
how does the direction that a tropical storm spins change depending on the hemisphere that it is in
- they spin anticlockwise in the northern hemisphere
- and clockwise in the southern hemisphere
what is the center of a storm called
the eye
what is the eye of the storm caused by and how large is it
- it is caused by descending air
- it can be up to 50km across
what is it like in the eye of the storm in terms of the conditions
- there is very low pressure
- light winds
- no clouds
- no rain
- and a high temperature
- it is very calm compared to the rest of the storm
what happens towards the edges of the storm as its intensity decreses
- the wind speeds fall
- causing clouds to become more scattered
- the rain becoming less intense
- and the temperature increasing