Module 6 : Earth's Processes Flashcards

1
Q

(Earth’s Changing Surface Part 1 : Plate Tectonics)

What is the theory of continental drift? What information was Wegener lacking when he created his hypothesis?

A
  • Wegener’s Idea : continents “fit” together, geologic and fossil similarities, proposed idea of continental drift
  • scientists rejected Wegener’s idea because it did not contain enough evidence to support the theory
  • Wegener failed to provide a suitable mechanism that could cause the continents to move, couldn’t explain how continents moved
  • continents plow through solid rock, no viable mechanism
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2
Q

(Earth’s Changing Surface Part 1 : Plate Tectonics)

What is the role of convection currents in plate tectonics?

A
  • circular currents in the mantle caused by the magma being heated by the core off the Earth
  • they help to drive the movement of the rigid plates making up the earth’s surface
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3
Q
(Earth's Changing Surface Part 2 : Plate Boundaries)
At which kind of plate boundary would you expect to see the following : 
(A) rift valleys
(B) subduction
(C) lateral faults
(D) mid-ocean ridge
(E) volcanoes
(F) chains of volcanic islands
(G) very tall non-volcanic mountains
A

(A) rift valleys : divergent plate boundary
(B) subduction : convergent boundary
(C) lateral faults : transform boundary
(D) mid-ocean ridge : divergent boundary
(E) volcanoes : divergent and convergent boundary
(F) chains of volcanic islands : divergent boundary
(G) very tall non-volcanic mountains : continental continental convergent boundary

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4
Q

(Earth’s Changing Surface Part 3 : Weathering and Erosion)

What is weathering?

A
  • breakdown of rock into smaller pieces from exposure to wind, water, or biological forces
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5
Q

(Earth’s Changing Surface Part 3 : Weathering and Erosion)

What is the difference between mechanical and chemical weathering?

A
  • mechanical weathering : type of weathering in which rock is PHYSICALLY broken into smaller pieces
  • chemical weathering : process that breaks down rock through CHEMICAL changes
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6
Q
(Earth's Changing Surface Part 3 : Weathering and Erosion)
Describe the following types of mechanical weathering. For each type, describe where these forces are likely to occur, what their action does to the rock, and what the resulting changes to the Earth's surface will be : 
(A) frost wedging
(B) exfoliation
(C) thermal expansion
(D) crystal growth
(E) tree roots
(F) abrasion
A

(A) frost wedging :
- mechanical breakup of rock caused by expansion of freezing water in cracks and crevices
(B) exfoliation :
- rock that cracks into layers because of pressure release physical
(C) thermal expansion :
- as sea and ocean temps increase, water molecules near the surface move further apart, so that water volume increases and the sea level rises
- also daily heating and cooling of rocks do not seem to have an effect
- sudden exposure to high temperature though such as in forest fires or a grass fire may cause expansion and eventual breakage of rock
(D) crystal growth :
- salts from sea water can crystallize in pores
- cracks in rocks and the pressure exerted by the growing salt crystals can cause rocks to break apart
(E) tree roots :
- plant roots can extend into fractures and grow, causing expansion of fracture
- growth of plants can break rock
(F) abrasion :
- removing small pieces of rock over time by wind or water
- slowly the rock is just worn away, causes the rounding of angular pieces

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7
Q

(Earth’s Changing Surface Part 3 : Weathering and Erosion)
Describe the following types of chemical weathering :
(A) dissolution
(B) oxidation
(C) hydrolysis

A

(A) dissolution :
- breaking minerals into ionic constituents
- all of the mineral is completely dissolved by water
(B) oxidation :
- chemical change in which a substance combines with oxygen, as when iron oxidizes, forming rust
(C) hydrolysis :
- breaking down complex molecules by the chemical addition of water
- H+ or OH- replaces an ion in the mineral

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8
Q

(Earth’s Changing Surface Part 3 : Weathering and Erosion)

How does acid rain contribute to weathering?

A
  • acid rain contributes to weathering by chemically breaking down minerals are in rocks and soil
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9
Q

(Earth’s Changing Surface Part 3 : Weathering and Erosion)

What is erosion? How is it different than weathering?

A
  • natural process; weathered particles are removed from rocks; transported by streams, glaciers, wind or other mobile agents; rock normally angular and jagged; particle size decreases and edges are rounded off
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10
Q

(Earth’s Changing Surface Part 3 : Weathering and Erosion)
Explain the process of erosion due to gravity, surface water, ground water, wind, and glaciers. How do each of these create changes to Earth’s surface?

A

(A) gravity :
- causes water and glaciers to move downhill and particles carried by wind and water to settle
- can also cause landslides and mudflows; surface water
(B) surface water :
- carries sediment water to other areas
(C) groundwater :
- process of chemical weathering causes much ground water erosion including the formation of caves and sinkholes
(D) wind :
- primarily known for smoothing and rounding landscapes as sand and dust carried by wind wear away rocks and land surface
(E) glaciers :
- when large bodies of ice pick up rocks and soil as they move; can destroy forests, carve out valleys, alter the course of rivers and wear down mountains
- the type of erosion that can cause hills and moraines

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11
Q

(Earth’s Changing Surface Part 3 : Weathering and Erosion)

How do gravity and groundwater contribute to land subsidence?

A
  • water is pulled down from glaciers, rain, etc, due to gravity and therefore holds nutrients
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12
Q

(Earth’s Changing Surface Part 1 : Plate Tectonics)

What is the theory of plate tectonics? What evidence supports this theory?

A
  • theory that pieces of the Earth’s lithosphere are in constant motion, driven by convection currents in the mantle
  • evidence :
    • along sea floor spreading zones, the continents are separating from one another
    • as they spread apart, magma comes to the surface and becomes new continental crust
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13
Q

(Earth’s Changing Surface Part 4 : Convection)

What are convection currents? Draw a diagram of a convection current.

A
  • SEE PAPER
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14
Q

(Earth’s Changing Surface Part 1 : Plate Tectonics)

How did the discovery of sea floor spreading contribute to our understanding of plate tectonics?

A
  • World War II required submarine navigators to know the topography of ocean floor
  • Discovered contains wide variety of land forms
  • sediment is not uniform on ocean floors
  • new crust forms at new volcanic ridges
  • mid ocean ridge : formation of new crust
  • subduction zone : destruction of old crust
  • magnetic stripping : further evidence for sea floor spreading and subduction, poles exchange places, youngest crust at mid ocean ridges and oldest crust at subduction zone
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14
Q

(Earth’s Changing Surface Part 4 : Convection)

Explain how convection cells cause the following types of air movement in the atmosphere : local winds and Hadley cells

A
  • local winds :
    • winds that blow over short distances caused by unequal heating of Earth’s surface within a small area
    • uneven surface heating on small scale, air above warm surface rises and warms, rising air cools and sinks, air moved from high pressure to low pressure (wind)
  • Hadley cells :
    • a large-scale atmospheric convection cell in which air rises at the equator and sinks at medium latitudes, about 30 degrees north or south (aides in creating the trade winds), uneven surface heating on global scale, transports heat from Equator to poles, produces global pressure systems
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15
Q

(Atmosphere Part 1 : Components of Earth’s Atmosphere)

List the layers of Earth’s atmosphere from surface to space

A
  • troposphere :
    • weather occurs
    • lowest and thinnest layer
    • most gases of atmosphere
  • stratosphere :
    • ozone layer
    • temperature increases because of ozone absorption of UV rays
  • mesosphere :
    • middle, cold
  • thermosphere :
    • gets warmer
    • no well defined upper limit
    • absorbs much of the X-ray and UV radiation
  • exosphere :
    • exit, interface between Earth and space
    • beyond 500 km, atoms and molecules can escape to space.
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16
Q

(Atmosphere Part 1 : Components of Earth’s Atmosphere)

What is the ionosphere?

A
  • an area of the atmosphere containing positively charged particles called ions (Aurora Borealis or Northern Lights) and found in the upper mesosphere and lower thermosphere
  • not a true layer
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17
Q

(Atmosphere Part 1 : Components of Earth’s Atmosphere)

What components of the atmosphere are in fixed amounts? List them from most to least plentiful.

A
  • nitrogen, oxygen, argon, neon, helium, methane, hydrogen
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18
Q

(Atmosphere Part 1 : Components of Earth’s Atmosphere)

What components of the atmosphere are in variable amounts?

A
  • water vapor, carbon dioxide, ozone, carbon monoxide, sulfur dioxide, nitrogen dioxide, particles (pollen, dust)
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19
Q

(Atmosphere Part 1 : Components of Earth’s Atmosphere)

What role does carbon dioxide play in the atmosphere?

A
  • humidity : is the mass of water vapor a given volume of air contains; plays a role in weather
  • carbon dioxide
  • plant life : keeps plants alive
  • greenhouse effect
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20
Q

(Atmosphere Part 2 : Air Masses and Fronts)

Describe the different types of air masses.

A
  • maritime arctic : cool, moist, unstable :
    • Arctic
  • continental arctic : cool, dry, stable :
    • Greenland
  • maritime polar : cool, moist, unstable :
    • North Atlantic, Pacific Ocean
  • continental polar : cold, dry, stable : Alaska, Canada
  • maritime tropical : warm, moist, usually unstable :
    • Caribbean Sea, Gulf of Mexico
  • continental tropical : hot, dry, stable aloft, unstable at surface
    • Mexico, Southwestern U.S.
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21
Q

(Atmosphere Part 2 : Air Masses and Fronts)

Explain the difference in how the air masses are moving in a cold front versus a warm front.

A
  • cold front : cold air mass on the move, cold air sinks, forces warm air to lift above cold air
  • warm front : warm air mass rises
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22
Q

(Atmosphere Part 2 : Air Masses and Fronts)

What happens to the weather when a cold front moves into the area?

A
  • cold air moves under warm air which is less dense and pushes air up (produces thunderstorms, heavy rain, or snow)
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23
Q

(Atmosphere Part 2 : Air Masses and Fronts)

What happens to the weather when a warm front moves into an area? How is this different than a cold front?

A
  • warm air moves over cold air and brings drizzly rain or light snow and then are followed by warm and clear weather
  • less dense, warmer air mass flows upward over more dense cooler air, frontal lifting
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24
Q

(Atmosphere Part 2 : Air Masses and Fronts)

airmass

A
  • a volume of air that has a characteristic temperature and humidity throughout.
  • tends to remain intact as it travels
  • acquires temperature and moisture characteristics of its source region
25
Q

(Atmosphere Part 2 : Air Masses and Fronts)

front

A
  • associated with rapid changes

- boundary where air masses meet

26
Q

(Atmosphere Part 3 : Coriolis Effect and Storms)

What is the cause of the Coriolis effect?

A
  • causes moving air and water to turn left in the Southern Hemisphere and turn right in the Northern Hemisphere due to Earth’s rotation
  • deflection of wind varies according to speed and latitude : faster wind, greater direction; deflection greatest at poles, decreases to zero at equator
27
Q

(Atmosphere Part 3 : Coriolis Effect and Storms)

Give an example of the Coriolis effect.

A
  • hurricane formation :
    • do not form at equator
    • if in northern hemisphere the winds will flow counterclockwise
  • air travel :
    • flight path that might look arrow straight on a flat map actually appears curved on a globe
28
Q

(Atmosphere Part 3 : Coriolis Effect and Storms)

What affect does the Coriolis effect have on rotation in storms?

A
  • in the Northern Hemisphere, storms will rotate counterclockwise
  • in the Southern Hemisphere, storms will rotate clockwise
29
Q

(Atmosphere Part 3 : Coriolis Effect and Storms)

Describe the changes in weather associated with a low-pressure center (cyclone) and a high-pressure system (anticyclone)

A
  • low-pressure center (cyclone) :
    • usually associated with wetter, warmer and lousy weather; ascending air, horizontal winds, counterclockwise rotation, cyclonic rotation
  • high-pressure center (anticyclone) :
    • high pressure are created by sinking cold air
30
Q
(Atmosphere Part 3 : Coriolis Effect and Storms)
Explain the different types of storms : 
(A) thunderstorm 
(B) hurricanes 
(C) tornadoes
A

(A) thunderstorm :
- humid air rises, cools, and condenses into a single cumulus cloud
- when fed by unstable, moist air -> thundercloud, contains large amounts of energy
(B) hurricanes :
- rising warm air creates low pressure, winds rotate around a central low-pressure, continuous supply of energy from warm water - weakens as fuel is cut off (land fall or cooler water)
(C) tornadoes :
- rotating column of air that moves around a low-pressure cone, reaches from a thundercloud to the ground
- a funnel cloud is similar to a tornado, but it does not touch the ground

31
Q

(Atmosphere Part 4 : Greenhouse Effect)

What is the greenhouse effect?

A
  • anticipated increase in Earth’s temperature, caused by carbon dioxide (emitted by burning fossil fuels) trapping some of the radiation emitted by the surface
32
Q

(Atmosphere Part 4 : Greenhouse Effect)

Describe the greenhouse effect’s impact on our atmosphere.

A
  • “Greenhouse” gases in the air strongly absorb infrared radiation. This effectively traps more energy in the atmosphere, heating both the atmosphere and surface
  • Greenhouse gas molecules such as carbon dioxide absorb infrared radiation as vibrations of their chemical bonds.
  • With greenhouse gases in the atmosphere, our planet’s surface is 33 degrees (Celcius) warmer than it would be without the greenhouse effect, and water remains unfrozen over most of the Earth. Our technological civilization has been adding greenhouse gases to the atmosphere at an unprecedented rate, resulting in an enhanced greenhouse effect.
33
Q

(Atmosphere Part 4 : Greenhouse Effect)

Summarize the effects of human activities on the levels of greenhouse gases.

A
  • burning of fossil fuels

- deforestation

34
Q

(Atmosphere Part 4 : Greenhouse Effect)

greenhouse effect

A
  • warming of the atmosphere as terrestrial radiation is trapped by “greenhouse gases”
35
Q

(Studying the Earth Part 1 : Seismology)

What is a seismometer? What does it measure?

A
  • instruments that measure motions of the ground, including those of seismic waves generated by earthquakes, nuclear explosions, and other seismic sources.
  • records of seismic waves allow seismologists to map the interior of the Earth, and locate and measure the size of these different sources
36
Q

(Studying the Earth Part 1 : Seismology)

What is the Richter scale?

A
  • numerical scale used for expressing the magnitude of an earthquake on the basis of seismograph oscillations.
37
Q

(Studying the Earth Part 2 : Infrared Imaging)

What is infrared imaging? How does it relate to the electromagnetic spectrum? How is it used to study the earth?

A
  • thermal imaging cameras detect radiation in the infrared range of the electromagnetic spectrum and produce images of that radiation, called thermograms
  • since infrared radiation is emitted by all objects near room temperature, according to the black body radiation law, thermography makes it possible to see one’s environment with or without visible illumination
38
Q

(Studying the Earth Part 3 : Remote Sensing)

What is satellite remote sensing? How can it be used to study the earth?

A
  • use of satellites or other high-altitude devices to collect visual or other data on Earth’s surface.
  • may use lasers, visible light, radar, or other forms of electromagnetic radiation
  • used for : radar, collecting data for dangerous or inaccessible areas
    • analyzing changes in elevation, geology, land use, vegetation over time
    • studying changes in surface temperature
    • observing sea level, ice cap thickness and extent, glacial movements
39
Q

(Studying the Earth Part 4 : Radar)

What is radar, specifically Doppler radar? How is it used to study weather? How is it related to the Doppler effect?

A
  • Radar :
    • use of reflected radio waves to create images
    • radio waves bounce off surfaces
    • travel and reflection time yields distance to surface
  • Doppler Effect :
    • change in perceived frequency of wave when source and observer are in relative motion
    • observable for all types of waves
  • Doppler Effect : Weather
    • radar signals bounce off clouds/precipitation
    • Doppler effect gives information about movements of clouds
  • Uses of Radar and Doppler Radar :
    • mapping and topographic imaging
    • studying and tracking weather and weather systems
    • severe weather warnings and predictions
40
Q

(Studying the Earth Part 5 : GPS)

What is the Global Positioning System (GPS)? How can it be used to study the earth?

A
  • satellites : 27 in orbit (24 functioning, 3 backup) orbits allow complete coverage of Earth’s surface
  • receiver units : determine distance to 4+ satellites, use triangulation to pinpoint location
  • navigation, determining locations of geologic features, mapping, studying plate movement, tracking organisms
41
Q

Quiz A

How do convection currents affect tectonic plate motion?

A
  • Convection cells transfer heat from the core to the crust contributing to the lateral movement of tectonic plates.
  • Convection currents drive tectonic plate motion - Heat from the core moves towards the crust causing convection currents in the oak tic asthenosphere. Warm buoyant magma rises, moves laterally, cools, and sinks contributing to the motion of the lithospheric plates.
42
Q

Quiz A

What statement correctly explains tectonic plate boundaries?

A
  • Earthquakes are common at transform plate boundaries because energy is released when plates slip past one another.
  • Transform boundaries occur when plates slide past one another in opposite directions. Frictions builds up at the boundary (fault line) and when it slips energy is released causing an earthquake.
43
Q

Quiz A

What statement correctly describes a landform associated with convergent plate boundaries?

A
  • Volcanic island chains form at oceanic-oceanic convergent plate boundaries.
  • Subduction of older, denser oceanic plates under less dense oceanic plates results in the melting of the overlying mantle. The resulting buoyant magma rises to the surface and forms volcanic island chains like the Aleutian Islands.
44
Q

Quiz A

How does ice wedging mechanically weather sandstone?

A
  • Repeated freezing and melting of water in the cracks of sandstone breaks the rock into smaller pieces.
  • Mechanical weathering causes rocks to break into smaller pieces while retaining their chemical properties. Ice wedging occurs when water makes its way into rocks and expands when it freezes and contracts when it melts. Over time the cycles of freezing and melting break off pieces of the rock.
45
Q

Quiz A

What statement correctly describes the formation of landforms due to the erosional action of glaciers?

A
  • Rocks and debris are picked up and carried in the ice; moraines and drumlins form when the ice melts and the debris is deposited.
  • Glaciers erode the land slowly by picking up rocks and other debris and carrying it to new locations. Moraines, drumlins, striations, and U-shaped valleys are landforms associated with glaciers.
46
Q

Quiz A

What landforms results from the activity of groundwater?

A
  • Sinkholes and caverns
  • Groundwater dissolves underground rocks and minerals forming sinkholes, caves, and caverns. Land subsidence occurs when sediment compresses because the groundwater in the pore spaces is removed.
47
Q

Quiz A

What statement correctly describes the gases in the Earth’s atmosphere?

A
  • Nitrogen is the most plentiful gas in the Earth’s atmosphere.
  • Nitrogen is the most abundant gas in the making up 78% followed by oxygen at 21%. The elements argon, neon, helium, methane, and hydrogen are permanent gases found in trace amounts. Water vapor, carbon dioxide, ozone, sulfur dioxide, and nitrogen dioxide are also found in the atmosphere in varying amounts.
48
Q

Quiz A

What statement correctly describes the weather changes associated with a warm front?

A
  • Increasing cloudiness and light precipitation followed by warm air and scattered clouds.
  • As warm air masses replace cold air masses (warm front), the warm air rises over the cold air forming nimbostratus, stratus, altostratus, cirrostratus, and cirrus clouds. Light to moderate precipitation precedes the warm front with warm air and scattered clouds following it.
49
Q

Quiz A

How does the Greenhouse Effect warm the Earth’s surface?

A
  • Greenhouse gases absorb radiated infrared energy from the ground and reemit it back to the Earth’s surface.
  • Water vapor and carbon dioxide are Greenhouse gases that are transparent to visible light emitted from the Sun. They absorb longer-wavelength infrared radiation and reemit it back to the Earth’s surface.
50
Q

Quiz A

What is measured using a seismometer?

A
  • Earthquake magnitude and epicenter location
  • Seismometers (seismographs) measure ground motion and determine earthquake magnitude and the amplitude of earthquake waves. They can also be used to determine the speed of P-waves, S-waves, and surface waves and to infer the structure of Earth’s interior.
51
Q

Quiz B

What correctly describes the role of convection currents in the atmosphere?

A
  • Convection currents cause warm, moist air to rise at the equator and cool, dry air to sink to 30 degrees north and south.
  • Convection currents are responsible for mixing the gases in the troposphere on a local and global basis. Globally, Hadley cells cause warm, moist air to rise at the equator and at 60 degrees north and south and for cool, dry air to sink at 30 degrees north and south at the poles.
52
Q

Quiz B

What statement correctly describes processes associated with mountain building?

A
  • As two continental plates collide, the rocks and minerals buckle and are pushed upward into a jagged mountain range.
  • The collision of two continental plates results in the formation of mountain ranges like the Himalayan mountain range. The force of the collision causes the granitic crust to fold into mountains.
53
Q

Quiz B

What landforms are found at a divergent boundary?

A
  • Ocean ridges and continental rifts
  • As plates move apart, material from the asthenosphere erupts through fissures. If the plate boundary is under the ocean. An ocean ridge forms (Mid-Atlantic ridge) and if the plate boundary is within a continents, a continental rift forms (East African Rift Zone).
54
Q

Quiz B

What is an example of chemical weathering?

A
  • Carbonic acid breaks down granite into potassium ions, clay minerals, and quartz.
  • Chemical weathering occurs when rocks decompose by chemical means. Water combines with carbon dioxide in the atmosphere forming carbonic acid which reacts chemically with granite forming potassium ions, clay minerals, and quartz.
55
Q

Quiz B

What statement describes how deltas are formed?

A
  • Rivers pick up sediment when moving downhill; when the river flows into the ocean, it’s speed decreases and the sediment is deposited at the mouth of the river.
  • Deltas form when a river or stream flows into a larger body of water. When the river enters the larger water body, it’s speed decreases and it deposits the sediment it is carrying to form a fan-shaped delta.
56
Q

Quiz B

What forms because of the erosional activity of glaciers?

A
  • Striations and U-shapes valleys
  • Striations form when rocks embedded in glacial ice scour the land creating parallel scratches. The movement of glaciers down V-shaped valleys erodes the sides and makes them rounded, wider U-shaped valleys
56
Q

Quiz B

How is the troposphere different than the other atmospheric layers?

A
  • It has a high density of gases which participate in convection currents, clouds, and precipitation.
  • The troposphere is the thinnest, densest, layer of the atmosphere and the movement of the molecules contributes to weather.
57
Q

Quiz B

What statement correctly describes the Coriolis Effect?

A
  • Winds blowing from the equator toward the poles appear to bend in the opposite direction from winds that blow from the poles toward the equator.
  • The Coriolis Effect is the apparent deflection of the wind because of the daily rotation of the Earth. Wind that blows from the equator toward the poles deflected in opposite directions than wind blowing from the poles toward the equator.
59
Q

Quiz B

How does deforestation affect the concentration of Greenhouse gases in the atmosphere?

A
  • The decreased amount of photosynthesis increases the concentration of atmospheric carbon dioxide.
  • Deforestation increases the amount of atmospheric carbon dioxide because excess carbon dioxide is used as a reactant in the photosynthesis. When trees are removed less carbon dioxide is removed from the atmosphere.
60
Q

Quiz B

The Global Positioning System (GPS) would be most useful studying what?

A
  • Changes in mountain height and tectonic plate movement
  • GPS is used to determine changes in the heir of surface features like mountains, to determine the distance tectonic plates have moved, and to map the Earth’s surface.