Weather Hazards Flashcards
How does insolation change depending on where you are?
Insolation at low altitudes, close to the equator have higher levels of insolation as the rays are spread over a smaller area.
At higher latitudes, at the poles the suns rays are spread over a great distance.
Why does warm air rise?
Because it is less dense than cooler air.
Why does cool air sink?
Because it is more dense than warmer air.
Rising air creates … pressure
Low pressure
Sinking air creates … pressure
High
How is wind created?
Air particles move form areas of high pressure to areas of low pressure
What is the coriolis effect?
The earth rotates so wind doesn’t move in a straight line
What are the conditions at the poles?
A belt of high pressure and a cold, dry climate
What is precipitation like at the poles and why?
Very low and falls mostly as snow
Because the cold air is less able to hold water vapour
What is precipitation like at the tropics of cancer and Capricorn and why?
Rainfall is often low
Dry air falls as part of the Hadley cell which creates arid conditions
What is precipitation like at the intertropical convergence zone and why?
Bursts of torrential rain and tropical storms
The rising air causes the torrential rain and the low pressure zone around the equator can grow waves of low pressure leading to tropical storms
What is precipitation like at the equator and why?
Rainfall is high and constant
Hot air rises, cooling quickly and condensing into droplets of rain
What is the formation of a tropical storm?
1) The suns rays warms the ocean - most in the tropics
2) This warms the oceans to a critical 27*C
3) This causes moist air to rise through the air in thermals which creates low pressure at the centre of the storm
4) As this cool air rises it condenses - creating clouds and rain
5) Some of the cool air sinks and creates the eye
6) Air rushes in from high pressure areas outside of the storm to the lower pressure areas inside the storm - creating wind
7) The whole storm rotates due to the earth’s spin
