end of term test. bruh another one

Question 1

what is a natural hazard?

Answer 1

a natural event that poses risks to humans and property.

Question 2

whats the difference between a natural hazard and a natural event?

Answer 2

a natural event doesn’t effect anybody or anything whereas a natural hazard poses a threat to humans.

Question 3

when does a natural hazard become a disaster?

Answer 3

when it becomes a potential risk to humans

Question 4

what are the 4 types of natural hazards?

Answer 4

tectonic, atmospheric, geomorphological and biological

Question 5

what are tectonic hazards?

Answer 5

hazards associated with the movement of the tectonic plates

Question 6

what are atmospheric hazards?

Answer 6

hazards associated with weather and climate events

Question 7

what are geomorphological hazards?

Answer 7

hazards associated with the processes occuring on the earths surface

Question 8

what are biological hazards?

Answer 8

hazards associated with the living world

Question 9

what is the fatalistic approach?

Answer 9

if it happens it happens, its all part of living in this area

Question 10

what is the acceptance approach?

Answer 10

we know hazards happen but we continue to live in this area because it has many advantages

Question 11

what is the adaption approach?

Answer 11

events can be prevented and warnings given. the area is made safer with modern technology so even if a disaster occurs few people will be affected.

Question 12

inner core:

Answer 12

this is solid and is the densest part of the planet and is composed of iron and nickel with a temperature of over 5500ºC

Question 13

outer core:

Answer 13

its liquid and 1228km in diameter

Question 14

mantle:

Answer 14

the mantle surrounds the core.its the thickest layer mainly composed of iron and magnesium. the rocks flow slowly as covection currents

Question 15

crust:

Answer 15

the thinnest and outermost layer and has the coolest, least dense rocks.

Question 16

what are the 2 types of crusts?

Answer 16

oceanic and continental

Question 17

what is oceanic crust?

Answer 17

its composed mainly of relatively dense basalt rock and is around 6-10km thick

Question 18

what is continental crust?

Answer 18

its composed of less dense igneous rock, metamorphic and sedimentary rock and can be up to 70km thick beneath major mountain ranges.

Question 19

what was alfred wegners theory?

Answer 19

that all the continents were once joined together. he named this supercontinent, pangea.

Question 20

how does a conservative plate margin move?

Answer 20

(passive-North American and Pacific Plates) Plates slide past each other in opposite directions, or in the same direction but at different speeds. this is responsible for earthquakes e.g. San Andreas fault, USA.

Question 21

how does a destructive plate margin move?

Answer 21

(compressional-Nazca and South American plates) Here two plates are moving together (slab pull). When the denser plate subducts, friction causes it to melt and become molten magma. the magma forces its way up to the surface to form a volcano e.g. Cotopaxi. This margin is also responsible for devastating earthquakes, explosive eruptions, fold mountain ranges e.g. Andes and ocean trenches e.g. peru - chile.

Question 22

how does a constructive plate margin move?

Answer 22

(tensional - North Amercian and Eurasian plates) Here 2 plates are moving apart (slab push) causing new magma to reach the surface through the gap. volcanoes formed along this crack cause a submarine mountain range such as those in the Mid Atlantic Ridge.

Question 23

how to tectonic plates move?

Answer 23

these plates move due to convection currents in the mantle and where they meet tectonic activities occur.

Question 24

what is the focus?

Answer 24

the point underground at which pressure release takes place

Question 25

what is the epicentre?

Answer 25

the spot on earths surface directly above the focus

Question 26

what is a fault line?

Answer 26

a break in the ground that occurs when the earth’s tectonic plates move or shift and are areas where earthquakes are likely to occur.

Question 27

what are seismic waves?

Answer 27

these radiate from the focus when pressure is released like the ripples in the water when a rock is thrown in a pond

Question 28

what are aftershocks?

Answer 28

minor earthquakes that follow on from the main event and may last for months afterwards.

Question 29

How are earthquakes caused?

Answer 29

Earthquakes are caused when two moving plates (convection currents) become locked causing friction to build up. from this stress, the pressure will eventually be released, triggering the plates to move into a new postion. this movement causes energy in the form of seismic waves, to travel from the focus towards the epicentre. as a result, the crust vibrates triggering an earthquake.

Question 30

what is a primary effect?

Answer 30

a primary effect is what occurs directly due to the tectonic hazard

Question 31

what is a secondary effect?

Answer 31

a secondary effect is what happens as a result of the primary effect

Question 32

what is global atmospheric circulation?

Answer 32

Atmospheric circulation is the large-scale movement of air by which heat is distributed on the surface of the earth.

Question 33

what happens as the air heats?

Answer 33

it rises causing low pressure(wet). as it cools, it sinks, causing high pressure. Winds move from high to low pressure. they curve because of the Coriolis effect (the turning if the earth)

Question 34

what is a hadely cell?

Answer 34

the largest cell which extends from the equator to 30-40º. air heats, rises condenses forming rain and separates before descending at 30-40º.

Question 35

What is a Ferrel Cell?

Answer 35

the middle cell where air sinks over deserts and flows towards the 50º. this warm air hits cold polar air, rises giving rain over the UK (50ºN) some air moves poleward/equator wards.

Question 36

what is a polar cell?

Answer 36

the smallest cell occurs 60-90º north and south. rising air over (50º) moves towards the Poles and sinks at the poles moving towards the equator.