global atmospheric pressure

Question 1

what is the word called when the sun heats the earths surface unevenly? and where is it greatest at?

Answer 1

insolation and at the equator

Question 2

winds blow from the areas of high pressure to the areas of low pressure transferring heat away from the …

Answer 2

equator

Question 3

what is a low and high pressure belt?

Answer 3

low-warm rising air

high-cool falling air

Question 4

what are the three cells in each hemisphere?

Answer 4

Hadley, Ferrel and Polar

Question 5

what happens at the equator?

Answer 5

at the equator the sun warms the earth which transfers heat to the air above causing it to rise. this creates a low pressure belt. as the air rises it cools and condenses forming clouds and rain.

Question 6

from the equator what type of air moves out 30 degrees north and south of the equator

Answer 6

cool dry air

Question 7

what happens at 30 degrees north and south of the equator

Answer 7

the cool air falls creating a high presser belt with cloudless skies and very low rainfall

Question 8

at 30 degrees what happens when the cool air reaches the grounds surface

Answer 8

moves as surface winds either back towards the equator or towards the poles

Question 9

what are surface winds blowing towards the equator called?

Answer 9

Trade winds. They blow from the SE in the southern hemisphere and NE in the Northern hemisphere

Question 10

what are surface winds blowing towards the poles called

Answer 10

westerlies-they blow from the south west in the northern hemisphere and north west in the southern hemisphere

Question 11

what happens at 60 degrees of the equator?

Answer 11

the warmer surface winds meet the colder air from the poles. the warmer air is less dense than the cold air so it is forced to rise creating low pressure and frontal rain (rain that forms where the warm and cold air masses meet). some of the air moves back towards t he equator and the rest moves towards the poles

Question 12

what happens at the poles?

Answer 12

at the poles the cool air sinks, creating high pressure, the high pressure air is drawn back towards the equator as surface winds

Question 13

what are ocean currents

Answer 13

they are large scale movements of water that transfer heat energy away from warmer to cooler regions

Question 14

what are surface currents

Answer 14

they are caused by winds and help transfer heat away from the equator, e.g. the Gulf Stream brings warm water from the Caribbean and keeps Western Europe warmer than it would otherwise be

Question 15

what are deep ocean currents driven by?

Answer 15

water density

Question 16

what happens as water freezes at the poles?

Answer 16

the surrounding water gets saltier increasing its density

Question 17

what happens as water gets denser?

Answer 17

it sinks causing warmer water to flow in at the surface-creating a current. this warm water is cooled and sinks creating a current.

Question 18

the cycle of cooling and sinking moves water in a big loop round the Earth. what is this known as

Answer 18

thermohaline circulation

Question 19

what are pressure belts caused by?

Answer 19

global atmospheric circulation

Question 20

what are the four different climate zones?

Answer 20

temperate, arid, Polar and tropical

Question 21

what is the temperate zone?

Answer 21

A low pressure belt at about 60 degrees N/S caused by rising air from two cells meeting means rainfall is frequent. Located between the tropics and poles. temperate zones have moderate summers and winters.

Question 22

what is the arid zone?

Answer 22

sinking air from the Hadley and Ferrel cells meeting causes high pressure. rainfall is very low for almost all or most of the year

Question 23

what is the polar zone?

Answer 23

sinking air from the polar cells creates an area of high pressure at the poles. temperatures are low all year round and there’s very little rainfall.

Question 24

what is the tropical zone?

Answer 24

rising air from the two Hadley cells meeting causes low pressure. temperatures are hot all the time and rainfall is high.

Question 25

what is the Hadley cell

Answer 25

the equator is intensely heated by the sun
rising air=low pressure
rising air cools it forms clouds=hot humid weather with high rainfall
air starts to move towards the north and south poles
sinks at 30 degrees north/south = high pressure
sinking air warms and dries=low rainfall deserts
air flows back to the equator = trade winds
0 degrees = tropical climate
30 degrees = desert climate

Question 26

what is a Ferrel cell

Answer 26

30-60 degrees N/S
winds pulled towards the poles pick up moisture as they travel over oceans
warm moist air meets cold air at 60 degrees
warm air from tropics=light
cold air from poles= dense
warm air rises above the cold air
causes low pressure= unstable weather conditions
uk weather caused by this

Question 27

what is a polar cell

Answer 27

air sinks forming high pressure (polar high)
cold air flows towards lower latitudes
air mixes at 60 degrees to form polar front