Brainscape's Knowledge GenomeTM

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


See full index

6-Understanding Planet Earth > Chapter 19: Global Change in the Earth System > Flashcards

Chapter 19: Global Change in the Earth System Flashcards

1
Q

Why does the Earth change constantly?

A
  • A plastic asthenosphere permits tectonic plate motion.
  • A star is close enough to warm Earth and its atmosphere.
  • Liquid water is possible; thus, weathering and erosion.
  • Biotic evolution continually modifies the biosphere.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Life on Earth is due to interactions among the:

A
  • Lithosphere
  • Atmosphere
  • Hydrosphere
  • Biosphere
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the “Earth System” composed of?

A

The “Earth System” is composed of these physical components interacting with the biosphere.

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

What are the types of changes?

A
  • Gradual change
  • Catastrophic change
  • Unidirectional change
  • Cyclic change
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Unidirectional changes include:

A
  • Evolution of the solid Earth
  • Formation of the Moon
  • Evolution of the atmosphere and oceans
  • Evolution of Life
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Explain how evolution of the solid Earth is a unidirectional change

A
  • Planetesimal accretion

- Melting and differentiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Explain how formation of the Moon is a unidirectional change

A
  • Mars-sized protoplanet collides
  • Mantle blasted into space
  • Debris coalesced to form the Moon
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Explain how evolution of the atmosphere and oceans is a unidirectional change

A
  • Volcanic gases created an early atmosphere.
  • CO2, H2O, N2
  • Liquid water condensed to form the oceans.
  • Photosynthetic organisms appeared.
  • O2 becomes a significant component of the atmosphere.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Explain how evolution of life is a unidirectional change

A
  • Life appeared on Earth about 3.8 Ga.
  • Multicellular organisms appeared in Late Proterozoic and early Phanerozoic.
  • Life inhabits all regions, within a few km of Earth’s surface.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Give examples to physical cycles

A
  • the supercontinent cycle

- the rock cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Explain the supercontinent cycle

A
  • Plate tectonics drives continental movement.
  • Ocean basins open and close.
  • Continental landmasses collide and rift apart.
  • Supercontinents (like Pangaea) have formed several times.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Explain the rock cycle

A

there are three types of rock:

  • Igneous—cooled from a melt.
  • Sedimentary—made of weathered and eroded materials
  • Metamorphic—rocks altered by heat and pressure

One rock type may transform into any other type.
The atoms in rocks are constantly being rearranged.

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

How do climate studies reveal our past and suggest our future?

A
  • Distinguish kinds of climate changes
  • Establish rates at which these changes occur
  • Determine the effects on Earth and its inhabitants
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the methods of climate studies?

A
  • Paleoclimates—investigations of past climatic variation

- Computer simulations—modeling past and future changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the greenhouse effect?

A
  • H2O, CO2, and CH4 in Earth’s atmosphere absorb thermal energy and reradiate it, warming the lower atmosphere.
  • This is called the greenhouse effect.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are paleoclimates? Give an example

A

Past climates are interpreted by datable Earth materials that are climate-sensitive.

E.g. Stratigraphic records—sequences of rock strata

  • Depositional environments are often climate-sensitive.
  • Glacial tills—cold and continental
  • Coral reef— tropical marine
17
Q

How do oxygen isotopes determine paleoclimates?

A
  • Oxygen isotopes—two isotopes: 16O and 18O
  • 16O water evaporates faster than 18O water.
  • 18O/16O in ice cores reveal the temperature in which snow formed.
  • Oxygen isotope ratios are preserved in carbonate shells of organisms.
  • The oxygen in CaCO3 shells mirrors oceanic 18O/16O.
  • Sea-floor sediments preserve ocean chemistry and temperature changes.
18
Q

here have been at least _____ major icehouse periods in Earth’s geologic history.

A

five

19
Q

What causes long-term climate changes?

A
  • Complex interactions across the Earth System
  • Plate tectonics modifies the position of continents.
  • Uplift of land surfaces influences atmospheric circulation.
  • Formation of coal and oil removes carbon from atmosphere.
  • Evolution of life affected atmospheric composition.
20
Q

Short-term climate changes regulated by several factors:

A
  • Fluctuations in solar radiation and cosmic rays
  • Changes in Earth’s orbit and tilt
  • Changes in volcanic emissions
  • Changes in ocean currents
  • Changes in surface albedo
  • Abrupt changes in concentrations of greenhouse gases
21
Q

How did humans impacted the Earth’s System?

A
  • Prehistoric humans were few, having a small impact. Today, humans are a huge force of planetary change.
    -Exponential population growth aided by advancements in:
    Industry, agriculture, technology, and medicine; fueled by a suitable supply of natural resources
  • Human demands often rival or exceed some natural processes.
    -Landscape modifications
  • Ecosystem modification—balances are destabilized. Destroys habitats
  • Pollution—materials that harm life forms and resources
  • Modern human society generates contaminants.
  • ## Recent global warming—human greenhouse gas additions alter climate.
22
Q

How do landscape modifications affect the Earth’s System?

A

Human-induced erosion may exceed natural processes.

23
Q

How do ecosystem modifications affect the Earth’s System?

A
  • Human-caused changes occur faster than indigenous organisms can adapt.
  • Rainforest decline is largely the result of human activity.
  • Deforestation
  • Overgrazing
  • Agriculture
  • Urbanization
24
Q

How does pollution affects the Earth’s System?

A

materials that harm life forms and resources

25
Q

How do contaminants affect the Earth’s System?

A
  • Contaminating materials are numerous and diverse.

- They are produced so fast that the natural environmental systems can’t absorb or modify/neutralize them.

26
Q

Explain how human greenhouse gas additions alter climate

A
  • O2 in the atmosphere has steadily climbed since the industrial revolution began.
  • Ice core data show atmospheric CO2 in 1750 was ~ 280 ppm.
  • In 1958, CO2 was ~315 ppm; in 2010, CO2 was ~390 ppm
  • Human additions of CO2 and CH4 exceed natural removals.
  • Fossil fuel combustion (CO2)
  • Rice-paddy decay (CH4)
  • Cow flatulence (CH4)
27
Q

Thousands of observations worldwide have documented effects of recent global warming such as:

A
  • Large ice shelves, like the Larsen B along the Antarctic Peninsula, are breaking up.
  • The summer melt line indicates that melting of the Greenland ice sheet is accelerating.
  • Valley glaciers worldwide are retreating.
  • Arctic Ocean sea-ice is reduced.
28
Q

The predicted effects of global warming are:

A
  • Stonger storms due to a more vigorous hydrologic cycle: - Higher sea-surface temperatures
  • Greater evaporation
  • Greater differential pressures
  • 2005 set a number of storm records
  • A rise in sea level
  • Warming will accelerate this trend by:
  • Thermal expansion of seawater
  • Melting ice
29
Q

Many scientists think that global warming could lead to:

A
  • Interruption of the oceanic heat conveyor system.
  • Polar ice meltwater is freshwater.
  • Would dilute surface ocean water near the poles.
  • This freshwater won’t sink and move southward.
  • Thermohaline circulation would stop preventing warm water from flowing northward.
30
Q

What is going to happen to Earth’s System in millions of years?

A
  • Earth’s surface will be different.
  • Plate tectonics will reshuffle continents.
  • Erosion will reshape the landscape.
  • Seas will invade or expose land.
  • Homo sapiens may no longer be present.
  • A new species of hominids might have evolved by then.
31
Q

What will happen to the Sun in 5 billion years?

A

In about 5 billion years, the Sun will run out of fuel and become a red giant.

  • Earth will dry out.
  • It will become vaporized.

6-Understanding Planet Earth (18 decks)

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