Winds And Air Masses *G11

Question 1

What are planetary winds

Answer 1

Major winds that blow all year over large expanses of earth’s surface

Question 2

Do planetary winds blow directly north/south

Answer 2

No, they are deflected by Coriolis force

Question 3

Land and water surfaces heat and cool at different rates, therefore…

Answer 3

They have differences in pressure

Question 4

Air mass definition *3

Answer 4

A large volume of air with consistent temperature,
atmospheric pressure and
humidity

Question 5

What does is mean when an air mass is unstable

Answer 5

Air within is likely to rise, condense and rain

Question 6

What does is mean when air masses are stable

Answer 6

Air within is subsiding and warm so rain is unlikely

Question 7

Air masses cover areas that are…

Answer 7

Uniform

Question 8

What are the types of air masses *4

Answer 8

*equatorial
*polar
*tropical
*arctic + antarctic

Question 9

Give characteristics of equatorial air masses *3

Answer 9

*covers equatorial oceans
*unstable
*hot moist air

Question 10

Give characteristics of tropical air masses *3

Answer 10

*near the tropics
*hot,dry air
*stable

Question 11

Give characteristics of polar air mass *3

Answer 11

occurs 50and 60* of equator
*cool air
*unstable

Question 12

Give characteristics for arctic/antarctic air masses *3

Answer 12

*occur at poles
*very cold
*stable

Question 13

Maritime air masses form…

Answer 13

Over sea

Question 14

Continental air masses form…

Answer 14

Over land

Question 15

What are monsoons

Answer 15

Seasonal winds that blow in particular tropical regions

Question 16

Explain how monsoons affect weather in winter *3

Answer 16

Inner land is colder than the seas (Siberian plateau)
*cold air sinks and causes high pressure
*these winds (from the north) blow over land (SE Asia)
*this creates dry, pleasant weather

Question 17

Explain how monsoons affect weather in summer *3

Answer 17

Inner land is hotter than seas (Siberian plateau)
*winds (from the south) blow towards the land (SE Asia), bringing moist air
*condensation occurs and there are heavy downpours of rain
*this creates wet and warm weather

Question 18

What are fohn winds

Answer 18

Warm dry winds that descend from the leeward side of the mountain

Question 19

Leeward side definition

Answer 19

Side where winds descend and warm up

Question 20

Windward side definition

Answer 20

Side where winds (usually from sea) rise and cool down

Question 21

Lapse rate definition

Answer 21

Rate where temperature changes in the atmosphere with altitude
Or rate of cooling

Question 22

What is the Dry Adiabatic Lapse Rate *2

Answer 22

The rate which unsaturated air decreases with temperature an increase of height
1C per 100m

Question 23

What is the the Wet Adiabatic Lapse Rate *2

Answer 23

The rate which the temperature of saturated air decreases with an increase of height
0.5C per 100m

Question 24

Explain the cycle of fohn winds *4

Answer 24

*moist air rises, then cools at DALR
*when condensation begins, rising air cools at WALR
*cooling > condensation > rain/snow on windward side
*cold air sinks, then warms as it descends at leeward side

Question 25

What do fohn winds cause

Answer 25

Serious natural disasters (drought, wildfire, floods)