How does the Coriolis effect influence wind movements in the southern hemisphere?
As the earth spins from west to east the wind is deflected to the left making them south easterly winds.
In the northern hemisphere the wind is deflected to the right.
What is the name for the south easterly winds flowing from the sub-tropical ridge to the equatorial trough?
South-east trade winds.
What are the lines on a synoptic chart called?
Isobars
What is the relevance of pressure gradients
a greater gradient (difference in two pressures) will cause stronger winds
In which direction does air converge in the southern hemisphere?
clockwise
In which direction does air diverge in the southern hemisphere?
counter clockwise
What are lines of equal temperature called?
Isotherms
What does the word ‘cyclonic’ mean?
As the art rotates
Which pressure system is cyclonic and which is anticyclonic?
low pressure is cyclonic
high pressure is anticyclonic
In the southern summer what causes the monsoon season in the northern parts of Australia?
The north east trades swing left after crossing the equator on their way to the equatorial trough and become the north west monsoons. At the trough they converge with the south east trades producing a strong lifting effect.
Will high speed or lower speed winds hold to the trend of the isobars better?
high speed
As winds slow down they tend to become more influenced by what force?
The pressure gradient force
What is a geostrophic flow?
Only occurs when the isobars are straight. When there is a balance between the Coriolis force and the pressure gradient force which results in the winds flowing perfectly straight. This straight flow is called geostrophic.
When flying towards a high pressure system which way will the wind be coming from?
Winds would come from the left.
Winds would come from the right if flying towards a low pressure system.
Below 3000ft does the wind sway in favour of the Coriolis effect or the pressure gradient force?
pressure gradient force due to the the surface layer slowing down the wind and reducing the Coriolis effect.
What is the name for when the wind moves to the left?
Backing
What is the name for when the direction of the wind moves to the right?
Veering
How does the speed and direction of wind change within the surface layer over the land?
Speed drops by 2/3 and direction veers by 30*
How does the speed and direction of wind change within the surface layer over the sea?
Speed drops by 1/3 and direction veers 10*
What is a squall?
An increase in wind by 16knots to more than 22knots and lasts longer than 60 seconds
What is a gust?
A rapid increase in wind speed that is short lived
Which way are winds travelling when you experience vertical wind shear?
Horizontally
When are land breezes the strongest?
Just before dawn when the temperature difference between the land and the water is greatest
