Non Frontal Depression

Question 1

Tropical revolving storm

Answer 1

~400/500 nm in diamter (up to 1000nm)
~wind in excess of 64 kts (classified as cyclone,hurricane or typhoone)
~hieght up to the tropopause
~average central pressure velue is about 960 hpa
~very steep pressure gradient
~fuel water vapuor evaporated from the warm sea and heavy precipitation
~shield of cirrus clouds circulates in the opposite direction of low level winds
Enrgy»ocean must be at least 26.5 C
Unstable atmosphere
Relative moist mid troposphere
Need Coriolis effect >5 /30 latitude north or south of the equator
Surface disturbance trigger
A low magnitude vertical windshear between the surface and the upper troposhere

Question 2

Tropical depression

Answer 2

Stage 1

~appearcance of low pressure
~surafce pressure wihtin 1000hpa
~organised circulation
~surface pressure chart reveals at least on closed isboar
~wind speed 20-34kts

Question 3

Tropical storm

Answer 3

Stage 2

~become more organised
~windspeed 35/63kts

Question 4

Tropical cyclone /hurricane/typhoon

Answer 4

~stage 3

~ windspeed more than 64kts

Question 5

The fastest wind usually found

Answer 5

On the right of the track in the northern hemisphere

On the left of the track in the southern hemishpere

Question 6

TRS EYE

Answer 6

FORMED DUE TO subsiding air 20/50km across
Calm in the ey
In the eye is warmer

Question 7

Decaying stage

Answer 7

If moves to land
Moves to colder ocean
Life span in avg 10 days

Answer 8

Tropical wave can be a trigger for a tropical revolving storm

Question 9

Frequency and seasonality

Answer 9

~between june and cotober in NH( most active in august /september)
~between december and april in SH ( most active jan /feb)

About 20 typhone each year
About 10 per elsewhere