Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Climate Change > Quiz 3 > Flashcards

Quiz 3 Flashcards

1
Q

Why is Earth so much colder than Venus?

A
  • The albedo is 30%
  • atmosphere is 90 times less dense
  • atmosphere has 0.04 (96% CO2 on Venus)
  • the greenhouse effect is 33°C.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How do we know that Earth was not frozen over its history in spite of much weaker early Sun?

A
  • Evidence from water-deposited sedimentary rocks

- Primitive life dates back to 3.5 billion years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the Faint Young Sun Paradox?

A

It talks about how the early Sun shone 25% to 30% weaker than today along with climate models showing that Earth should have been frozen even with greenhouse gases present.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How does chemical weathering work as a CO2 removal mechanism?

A

Chemical weathering of silica-rich rocks on the continents removes CO2 from the atmosphere, and part of the carbon is later stored in the shells of marine plankton and buried in ocean sediments.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the Snowball Earth hypothesis?

A

It is located in continents in low latitudes and there is increased rainfall and extreme chemical weathering.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the Characteristics of Venus?

A
  • The mean surface temperature 460°C
  • it receives 1.93 times more solar radiation
  • sulfuric acid clouds reflect 80% of incoming radiation
  • receives 50% of radiation received on Earth
  • the greenhouse effect is 285°C
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are examples of Greenhouse gases?

A 
CARBON DIOXIDE CO2 (0.04%)
METHANE CH4 (0.00018%)
WATER VAPOR (~1-3%)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

THE GREENHOUSE EFFECT

A
  • The greenhouse gases absorb outgoing IR radiation
  • Atmosphere radiates thermal IR radiation towards the surface
  • lower troposphere is heated from the Earth’s surface
  • greenhouse heating of Earth’s atmosphere is 32°C (Venus’ is 285°C)
  • W/o greenhouse heating Earth would be solid frozen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Volcanic input

A
  • The largest reservoir of carbon on Earth is in rocks (on Venus – in atmosphere)
  • Major input of CO2 to atmosphere is from volcanic activity and hot springs
  • Natural rates of CO2 input and removal are ~ balanced
  • W/o this input CO2 will be removed from atmosphere in ~4,000 years
  • Volcanic processes are not affected by the atmosphere
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Negative feedback from chemical weathering

A
  • When Earth’s climate warms, increased precipitation and vegetation cover increases chemical weathering
  • More CO2 removed from the atmosphere, hence moderate cooling
  • When Earth’s climate cools, precipitation decreases and vegetation cover becomes more sparse
  • More CO2 remains in the atmosphere, hence moderate warming
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Earth’s “thermostat”

A
  • The weakness of the early Sun was compensated by much higher concentrations of CO2 due to stronger volcanic activity
  • As the Sun brightened, climate warming resulted in more CO2 removed from atmosphere through chemical weathering – cooling effect
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Was there a Thermostat Malfunction?

A

Yes there was, evidence of several glaciations on all continents between 850 and 550 million years ago.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why are we not using the term “continental drift” suggested by Alfred Wegener in relation to the plate tectonics processes?

A

Lithospheric plates move across Earth’s surface at rates ranging from 1 to 10 cm per year

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Earth’s magnetic field

A
  • Earth’s magnetic field is generated by the rotating fluid outer iron core
  • Geomagnetic reversals: randomly distributed; average period 450,000 years
  • The last Polarity Reversal happened 780,000 years ago
  • Magnetic field protects the atmosphere against depletion by solar winds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Earth’s Crust and Upper Mantle

A
  • Oceanic crust – 5-8 km

- Continental crust – up to 35-40 km

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

igneous rocks

A

formed by cooling and solidification of molten rock

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

magma

A

general term for molten rock under the surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

lava

A

molten rock flows on the surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

pyroclastics

A

pieces of solid volcanic rock ejected in a volcanic eruption

20
Q

What was the Formation of the San Andreas Fault?

A

25 Million years ago the plate boundary changed from a subduction zone to a transform fault in which the San Andreas fault became a short segment between the two subduction zones. By 10 Million Years ago the Farallon Plate was subducted under the Pacific Plate.

21
Q

In Earth’s Internal Energy, what are the sources of heat energy?

A

compression of protoplanet matter along with radioactive decay in the Earth’s interior.

22
Q

In Earth’s Internal Energy, what does the Geologic Time show?

A

It shows geologic eras, periods, and epochs and we are living in Holocene, which started 10,000 years ago.

23
Q

What is the Composition of the Crust?

A

90 chemical elements making up over 4000 minerals, rocks of Earth’s crust are made up of minerals, and less than 20 minerals account for over 95% of the composition of the crust

24
Q

What are the three types of rocks?

A

igneous rocks, sedimentary rocks, and metamorphic rocks

25
Q

Intrusive igneous rocks

A

granites (they have visibly large crystals that are the evidence of a long process of cooling and crystallization below the surface).
 Intrusive rocks form batholiths (large masses of crystallized magma inside the crust), sills (smaller horizontal magmatic bodies), and dikes (vertical intrusive forms).

26
Q

Extrusive igneous rocks

A

basalts (consist of volcanic glass and small crystals that are hard to distinguish without a microscope - the evidence of fast cooling and crystallization on the surface or on the ocean floor).
 Examples: basalt, andesite, rhyolite
 Extrusive rocks crystallize from lava on the ocean floor or on the continental surface; crystallization happens very fast due to low temperatures on the surface compared to the temperature of lava (about 2000ºC).

27
Q

What are the processes of Sedimentary Rocks?

A

Disintegration, Transportation, Sedimentation, Stratification, Chemical cementation, and Consolidation

28
Q

Typical sedimentary rocks:

A

sandstone, limestone, shale

29
Q

Compaction

A

sediments packed from weight of overlying material

30
Q

Cementation

A

infilling of pore spaces by a cementing agent like SiO2, CaCO3, or Fe2O3

31
Q

Metamorphic rocks:

A

altered by heat and pressure

32
Q

contact metamorphism

A

rocks in contact with heat or pressure are altered

33
Q

regional metamorphism

A

large volumes of rock deformed during plate tectonics processes

34
Q

In the Oceanic and Continental Crust Composition, what does Basalts + Sedimentary rocks equal?

A

Oceanic crust in which the basalt density is 3 g/cubic cm

35
Q

In the Oceanic and Continental Crust Composition, what does Granites + Sedimentary Rocks equal?

A

Continental crust in which the granite density is lower, 2.7 g/cubic cm and it is less dense than the oceanic crust (basalts), in which it is lighter and floats higher than oceanic crust.

36
Q

In the Sea-Floor Spreading and Production of New Crust, what are the two pieces of evidence used to back up the Young Oceanic Crust theory?

A

sea floor basalts are not older than 180-200 million years ago and Earth’s magnetic field reversals, recorded by ocean floor basalts, give evidence of sea floor spreading.

37
Q

plate tectonics

A
  • 65-100 km thick
  • consist of both oceanic and continental crust, plates move slowly over asthenosphere
  • rate of seafloor spreading is around 1-10 cm per year, driven by the sinking of cold lithospheric plates back into asthenosphere and heat exchange (convection) between the mantle and the surface
  • the plates collide, deform and break up, three types of contacts between plates: they may diverge, converge, and slide laterally
38
Q

Divergent plate boundaries

A

most of the midocean ridges basaltic volcanism on the ocean floor in Iceland - on top of the Mid-Atlantic Ridge and on the continents in the East African Rift Valley (Basalts).

39
Q

What are Convergent Oceanic-Continental Plate Boundaries?

A
  • mountain ranges on the continental edges
  • deep oceanic trenches
  • granite volcanism
    (Ex: The Andes)
40
Q

What are Convergent Continental-Continental Plate Boundaries?

A
  • no subduction or volcanism
  • mountain ranges
  • frequent earthquakes
    (Ex: the Alps, the Himalayas, the Appalachians)
41
Q

What are Transform Plate Boundaries?

A

The lateral movement along the boundary line

  • slippage along deep vertical faults
  • no volcanism
  • high earthquake activity (Ex: the San Andreas Fault in California)
42
Q

What are Mantle Plumes?

A

They are hot spots which formed as a result of upwelling of abnormally hot magma within the mantle
- they provide heat exchange across the core-mantle boundary, they are stationary, and the lithospheric plate is moving above the stationary hot spot.
(Ex: the Hawaiian hot spot)

43
Q

Rift Valley: The East African Rift

A
  • linear-shaped lowland between mountain ranges created by a geologic rift (fault)
  • Formed on a divergent plate boundary
  • result of a crustal extension and thinning
44
Q

Oceanic-Oceanic Convergent Boundaries

A
  • deep ocean trenches
  • volcanoes on the ocean floor
  • volcanic island arcs
    Examples: the Aleutian Islands, the Mariana Islands
45
Q

Lithosphere

A

the crust + uppermost rigid mantle

46
Q

Asthenosphere

A

plastic layer that underlines the lithosphere

Climate Change (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions