Astro 105 Sfa Ch7 Earth And Terrestrial World

Front 1

What produces the most dramatic process that reshapes the surface of the Earth?

Back 1

When an asteroid or comet slams into Earth

Front 2

Name the 5 terrestrial worlds that looked quite similar when they were young.

Back 2

Mercury
Venus
Earth
the Moon
Mars

Front 3

Name the 2 terrestrail worlds that have surfaces that are densely covered by craters except in areas that appear to be volcanic plains?

Back 3

Mercury
the Moon

Front 4

What planet has the solary system's largest volcanoes?

Back 4

Mars

Front 5

What is the term referring to the action of a planet's surface that is continually being reshaped by volcanic eruptions, earthquakes, erosion and other geological processes?

Back 5

Geologically Active

Front 6

T or F
All terrestrial worlds have layered interiors.

Back 6

True

Front 7

List the 3 major categories of layers of the terrestrial worlds?

Back 7

1. core
2. mantle
3. crust

Front 8

What is the terrestrial worlds' layer that is the highest density material, consisting primarily of metals such as nickel and iron?

Back 8

Core

Front 9

What is the terrestrial worlds' layer that consists of rocky material of moderate density-mostly minerals that contain silicon, oxygen, and other elements?

Back 9

Mantle

Front 10

What is the terrestrial worlds' layer that has the lowest-density rock, such as granite and basalt

Back 10

crust

Front 11

What do we know about the Earth's metallic core?

Back 11

It consists of 2 layers:
1. inner core-solid
2. outer core-molten(liquid)

Front 12

In geology, how are interior layer categorized?

Back 12

By rock strength rather than density

Front 13

T or F
Rock mostly empty space between atoms and molecules

Back 13

True

Front 14

What is the term given to the Earth's outer layer that is cool and rigid rock?

Back 14

Lithosphere

Front 15

What does 'lithos" mean?

Back 15

Stone

Front 16

T or F
The Earth's lithosphere "floats" on warmer softer rock beneath.

Back 16

True

Front 17

What does the Earth's lithosphere consist of?

Back 17

1. crust
2. part of the upper mantle

Front 18

What is the term for the process by which gravity separates materials by density?

Back 18

Differentiation

Front 19

What tells us that all of the terrestrial worlds underwent differentiation at the same time in the past?

Back 19

The layered interiors

Front 20

T or F
All of the Terrestrial worlds must once have been hot enough inside for their interior rock and metal to melt and separate by density.

Back 20

True

Front 21

What happened to the dense metals during differentiation?

Back 21

The sank toward the center, driving less dense rocky material toward the surface

Front 22

Why were the terrestrial world's hot inside when they were young?

Back 22

1. planets gained heat from the process of formation itself
2. the metal and rock that made up the terrestrial planets included small amounts of radioactive elements

Front 23

T or F
None of the terrestrial worlds remain hot enough for liquid througout their interiors.

Back 23

True

Front 24

T or F
The terrestrial worlds differ in the amount of heat that they retain.

Back 24

True

Front 25

T or F
A large planet can remain hot for a longer time than a smaller planet.

Back 25

True

Front 26

What is the primary driver of geological activity.

Back 26

True

Front 27

What supplies the energy to move rock and reshape the surface?

Back 27

Heat

Front 28

T or F
Inside a planet, temperatures decrease with depth.

Back 28

FALSE
Inside a planet, temperatures rise with depth.

Front 29

What is the term for the process by which hot material expands and rises while cooler material contracts and falls?

Back 29

Convection

Front 30

What happens to hot rock within the mantle?

Back 30

It usually rises

Front 31

What happens to cool rock within the mantle?

Back 31

It gradually falls

Front 32

T or F
Mantle convection primarily involves molten rock.

Back 32

FALSE
Mantle convection primarily involves solid rock

Front 33

What is the primary factor in the strength of mantle convection and lithospheric thickness?

Back 33

Planetary size

Front 34

What limits volcanic and tectonic activity?

Back 34

A thick lithosphere

Front 35

Name the largest of the terrestrial planets

Back 35

Earth

Front 36

What planet is similar to Earth's in its internal heat?

Back 36

Venus

Front 37

Describe the size of Mercury and the Moon's lithospheres?

Back 37

Very thick, as demonstrated by no geological activity observed

Front 38

What is responsible for Earth's global magnetic field?

Back 38

Heat

Front 39

What does EArth contain that causes its magnetic field?

Back 39

Charged particles moving with the molten material in its liquid outer core

Front 40

What protects the Earth's surface from energetic particles that continually flow outward from the Sun with the solar wind?

Back 40

Earth's magnetic field

Front 41

What is the term for the Earth's protective bubble created by the magnetic field?

Back 41

Magnetosphere

Front 42

What is the term for the beautiful lights produced by the few particles that make it through the magetosphere that tend to be channeled toward the poles, where they collide with atoms and molecules in our atmosphere and produce

Back 42

Aurora

Front 43

T or F
None of the other terrestrial world have a magnetic field as strong as the Earths

Back 43

True

Front 44

List the 4 major geological processes that explain the Earth's surface features:

Back 44

1. impact cratering
2. volcanism
3. tectonics
4. erosion

Front 45

What is the term for the eruption of molten rock, or lava, from a planet's interior onto its surface

Back 45

Volcanism

Front 46

What is the term for the disruption of a planet's surface by internal stresses?

Back 46

Tectonics

Front 47

What is the term for the wearing down or building up of geological features by wind, water, ice and other phenomena of planetary weather?

Back 47

Erosion

Front 48

Name the only geological process that has an external cause?

Back 48

impact cratering

Front 49

What causes an impact crater to form?

Back 49

When an asteroid or comet slams into a solid surface.

Front 50

What is the Greek word for cup?

Back 50

crater

Front 51

T or F
We have never witnesses a major impact on Earth.

Back 51

True

Front 52

T or F
We think we have witnesses a major impact on Jupiter.

Back 52

True

Front 53

What is the theory explaining why most of Earth's impact craters have erased?

Back 53

Geological activity such as volcanic eruptions and erosion

Front 54

T or F
Few impacts have occurred since the heavy bombardment period of our solar system's history.

Back 54

True

Front 55

Name the 3 main reasons why molten rock tend to erupt:

Back 55

1. molten rock is generally less dense than solid rock, so it has a tendency to rise
2. molten rock may be squeezed by the surrounding solid rock, which drives the molten rock upward under pressure
3. molten rock often contains trapped gases that expand as it rises

Front 56

What is the process by which volcanic eruptions released some of their gas into the atmosphere?

Back 56

Outgassing

Front 57

List the 4 common gases released by outgassing:

Back 57

1. water vapor
2. carbon dioxide
3. nitrogen
4. sulfur bearing gases

Front 58

What is the dominant ingredient in our atmosphere?

Back 58

Nitrogen

Front 59

What is the example of tectonic activity created by surface compression?

Back 59

The Himalayas

Front 60

What is the example of tectonic activity created by surface stretching?

Back 60

The Red Sea

Front 61

What is the term given to the more than a dozen of pieces the Earth's lithosphere broke into by the underlying mantle convection?

Back 61

Plates

Front 62

What is the term given to the movement the Earth's plates make over and under each other?

Back 62

Plate tectonics

Front 63

What goes hand in hand with volcanic activity?

Back 63

Tectonic activity

Front 64

What is the blanket term for a variety of processes that break down or transport rock through the action of ice, liquid, or gas

Back 64

Erosion

Front 65

What causes many of the shaping of valleys

Back 65

Glaciers

Front 66

What causes the carving of canyons by river?

Back 66

Liquid (water)

Front 67

What causes the shifting of sand dunes?

Back 67

Wind

Front 68

What is the term for the layers of sediment erosion has piled into layers on the floors of oceans and seas?

Back 68

Sedimentary rock

Front 69

What caused the layers of rock seen in the Grand Canyon?

Back 69

erosion

Front 70

What is unique about earth's temperature and its affect on water?

Back 70

Its the only terrestrial planet where water exists in both liquid and solid form on the surface

Front 71

What percent of our atmosphere is oxygen?

Back 71

21%

Front 72

Where are all of the xrays absorbed in our atmosphere?

Back 72

High up

Front 73

T or F
Ultraviolet photons are absorbed high in the earth's atmosphere?

Back 73

FALSE,
Ultraviolet light passes through our atmosphere unhindered

Front 74

What protects us by only a small fraction from ultraviolet light?

Back 74

Ozone

Front 75

Where does the Earth's ozone reside?

Back 75

Primarily the middle layer or
the STRATOSPHERE

Front 76

What does the Sun emit most of its radiation in the form of?

Back 76

Visible light

Front 77

Why is our sky bright rather than dark? Why cannot see stars during the daytime?

Back 77

Because some of the light photons are scattered by the Earth's atmosphere

Front 78

T or F
Visible light consists of all the colors of the rainbow.

Back 78

True

Front 79

T or F
Not all colors of visible light scatter equally.

Back 79

True

Front 80

Why does our sky appear blue during the day?

Back 80

Because only the scattered blue light gets to us.

Front 81

Why is the Earth so much warmer than it would be from visible-light warming alone?

Back 81

Greenhouse effect

Front 82

What is the term for the process by which our atmosphere traps additional heat?

Back 82

Greenhouse effect

Front 83

T or F
Planetary temperatures are in the range in which they emit energy primarily in the form of infrared rather than visible.

Back 83

True

Front 84

When does the Greenhouse effect occur?

Back 84

Only when the atmosphere contains gases that can absorb infrared kight

Front 85

Name the 3 main gases that are good at absorbing infrared light:

Back 85

1. water vapor
2. carbon dioxide
3. methane

Front 86

Why does water vapor, carbon dioxide, and methane absorb infrared light easily?

Back 86

Because their molecular structures make them ;prone to begin rotating or vibrating when struck by a photon of infrared light.

Front 87

T or F
Greenhouse gases tend to slow the escape of infrared radiation from the lower atmosphere while their molecular motions heat the surrounding air

Back 87

True

Front 88

T or F
The more greenhouse gases present, the greater the degree of surface warming

Back 88

True

Front 89

What accounts for the Moon and Mercury's loss of internal heat and lack of significant atmosphere

Back 89

Their small size

Front 90

What has been the most important geological process on the Moon and Mercury?

Back 90

Impact cratering

Front 91

T or F
Not all regions of the Moon look the same.

Back 91

True

Front 92

What is the term given to the Moon's regions that appear smoother and darker?

Back 92

Lunar maria

Front 93

What is the latin word for "sea"

Back 93

Maria or mare

Front 94

What do lunar maria look like from afar?

Back 94

oceans and/or seas

Front 95

What are the lunar maria essentially circular?

Back 95

They are essentially flooded craters formed by molten rock that was formed by the decay of radioactive elements in the Moon's interior that arrived via impact of asteroids and comets

Front 96

When is it thought that the molten rock on the Moon welled up through the cracks in its lithosphere, flooding the largest impact craters with lava?

Back 96

3 - 4 billion years ago

Front 97

When did the lava floods occur on the Moon, before or after the heavy bombardment period?

Back 97

After the heavy bombardment period

Front 98

What is the only geological change on the Moon?

Back 98

A very slow sand-blasting of the surface by micrometeroites

Front 99

What is the term for the sand-sized particles from space that rain directly onto the surface of the Moon?

Back 99

micrometeroites

Front 100

Why does the lunar surface have a cover of thin powdery soil?

Back 100

Because of the micormeteroites

Front 101

How long will the astronauts' footprints left on the Moon last?

Back 101

Millions of years

Front 102

T or F
The Moon is considered to be geologically dead.

Back 102

True

Front 103

What terrestrial world's surface is very similar to the Moon's?

Back 103

Mercury

Front 104

How long does Mercury's days and nights last?

Back 104

3 months each

Front 105

Name the largest single surface feature on Mercury?

Back 105

Huge impact crater called:
CALORIS BASIN

Front 106

How large is the Caloris Basin?

Back 106

Spans more that half of Mercury's radius

Front 107

What is evident about the Caloris Basin that says that it was a violent impact?

Back 107

It multiple rings around its perimeter, and
evidence of violent surface shaking on the precise opposite side of Mercury from the Caloris Basin

Front 108

What are the most surprising feature of Mercury's surface?

Back 108

Its many tremendous cliffs-evidence of past tectonics quite different from anything we have found on any other terrestrial world

Front 109

What might have caused Mercury to have dramatically tall cliffs?

Back 109

Mercury may have simply shrank

Front 110

T or F
Mercury is geologically dead.

Back 110

True

Front 111

T or F
Mars is more geologically interesting and varied than the Moon but geologically less active than Earth or Venus.

Back 111

True

Front 112

How long is a Martian day?

Back 112

slightly longer than an Earth day

Front 113

What do the Mars' ice caps contain?

Back 113

frozen carbon dioxide

Front 114

Why does Mars have more extreme seasons than EArth?

Back 114

Mars has a more elliptical orbit putting it significantly closer to the Sun during the southern hemisphere summer and farther from the Sun during the southern hemisphere winter

Front 115

What drive Earth winds?

Back 115

primarily by effects of Earth's rotation and by heat flow from the equator to the poles.

Front 116

What drive Marian winds?

Back 116

strongly affected by its extreme seasonal changes.

Front 117

How cold does the Mars winter pole drop?

Back 117

-130C cold enough condense carbon dioxide into dry ice?
At the same time the frozen dry ice at the summer pole sublimates into carbon dioxide gas.

Front 118

What is the term for the process by which an ice turns to a gas without first melting into liquid?

Back 118

Sublimation

Front 119

HOw much does the total carbon dioxide of the Martian atmosphere move seasonally between the north and south polar caps?

Back 119

one-third

Front 120

T or F
Mars had a warmer and wetter past.

Back 120

True

Front 121

What is the reason why we are sending more spacecraft to Mars than any other planet?

Back 121

Conditions might have been enough for life to have arisen.
Its conceivable that such life could still survive in subsurface locales.

Front 122

T or F
No liquid water exists on the surface of Mars today.

Back 122

True

Front 123

T or F
Mars is either so cold as to freeze water immediately or so hot to vaporize water immediately.

Back 123

True

Front 124

T or F
Mars offers ample evidence of past water flows.

Back 124

True

Front 125

What is the most striking feature of Mars?

Back 125

The dramatic difference in terrain around different parts of the planet.

Front 126

Describe Mars's southern hemisphere:

Back 126

relative high elevation and is scarred by numerous large impact craters, including the large crater known as the Hellas Basin

Front 127

Where is the Hellas Basin located?

Back 127

In the southern hemisphere of Mars.,

Front 128

Describe the Mars northern plains:

Back 128

show few impact craters and tend to be below the average Martian surface level.

Front 129

What do the differences in crater crowding tell us about Mars?

Back 129

The southern highlands are a much older surface than the northern plains, which must have had their early craters erased by other geological processes.

Front 130

What was the most important geological process that occured in the Mars northern plains?

Back 130

Volcanism

Front 131

What is the name for the tallest known volcano in the solar system?

Back 131

Olympus Mons

Front 132

T or F
The Olympus Mons is large enough area to cover the size of Arizona.

Back 132

True

Front 133

How tall is the Olympus Mons?

Back 133

@26 kilometers above the average Martian surface level

Front 134

Compared to Mt. Everest, how tall is the Olympus Mons?

Back 134

3 times as tall as Mt. Everest

Front 135

What is the Tharsis Bulge?

Back 135

Located near Olympus Mons, Tharsis is @ 4,000 kilometers across, and most of it rises several kilometers above the avg Martian surface level.

Front 136

What is thought to have created the Tharsis Bulge?

Back 136

Created by a long-lived plume of rising mantle material that bulged the surface upward and provided the molten rock for the eruptions that built the giant volcanoes

Front 137

What is the most prominent tectonic feature on Mars?

Back 137

The long, deep system of valleys called Valles Marineris

Front 138

What physical feature on Mars extends almost a fifth of the way along the planet's equator, is as long as the US is wide and almost four times and deep as Earth's Grand Canyon?

Back 138

Valles Marineris

Front 139

T or F
Martian meteorites have hit the Earth.

Back 139

True

Front 140

T or F
some of the martian meteorites have been dated to be @ 180 million years old.

Back 140

True

Front 141

Describe some of the evidence of water we observe on Mars?

Back 141

1. appearance of dry river beds

Front 142

What is the only substance that could have been liquid under past Martian conditions and that is sufficiently abundant to have created such extensive erosion features.

Back 142

Water

Front 143

What are the "blueberries" found on Mars

Back 143

odd indentations suggesting that they formed in standing water, or possibly by groundwater percolating through rocks.

Front 144

What do the "blueberries" contain?

Back 144

iron rich mineral hematite, and other rocks containing the sulfur-rich mineral jarosite

Front 145

Name the 2 minerals found on mars that form in water?

Back 145

1. hematite
2. jarosite

Front 146

What is the strongest evidence that water existed on Mars?

Back 146

Gullies on crater and channel walls that are similar to gullies we see on almost any eroded slope on Earth

Front 147

Based on what we know, what is thought to be the age of these gullies since that are still visible?

Back 147

No more than a few million years old.

Front 148

When is it thought that Mars had a wetter and warmer period?

Back 148

Probably more than 3 billion years ago.

Front 149

T or F
Mars underwent major and permanent climate change, turning a world that was at least sometimes wet and warm into a frozen wasteland.

Back 149

True

Front 150

T or F
Mars probably had a dense atmosphere from volcanic outgassing, with a stronger greenhouse effect than it has today.

Back 150

True

Front 151

Where is it thought that Mars carbon dioxide went?

Back 151

Lost to space

Front 152

T or F
Mars lacks ultraviolet-absorbing gases.

Back 152

True

Front 153

T or F
Because Mars lacks ultraviolet-absorbing gases, water molecules would have been easiy broken apart by ultraviolet photons

Back 153

True

Front 154

Why is Mars the "red" planet?

Back 154

It is thought that the oxygen that was drawn out of the atmosphere through chemical reactions literally rusted the Martian rocks

Front 155

How do we study Venus's geological features?

Back 155

With radar

Front 156

What is the term for bouncing radio waves off the surface and using the reflection to create three-dimensional images of the surface?

Back 156

Radar mapping

Front 157

How did radar mapping of Venus occurr?

Back 157

When the Magellan spacecraft from 1990-1993 mapped the surface of Venus discerning features as small as 100 meters across.

Front 158

What are the coronae found on Venus?

Back 158

circular in shape, they were probably made by hot, rising plumes of mantle rock.

Front 159

T or F
Venus is not geologically active.

Back 159

FALSE
Venus is almost certainy geologically active today.

Front 160

Why do we think the surface of Venus is geologically young?

Back 160

Because it has relatively few impact craters

Front 161

What do Venus clouds contain?

Back 161

Sulfuric acid which is made from sulfuric dioxide

Front 162

What does the presence of sulfuric acid indicate?

Back 162

That outgassing must continue to supply sulfur dioxide to the atmosphere

Front 163

What is the biggest difference between the geology of Venus and that of Earth?

Back 163

The lack of erosion

Front 164

Why isn't Venus more eroded?

Back 164

1. Venus is far too hot for any type of rain or snow on its surface
2. Venus has virtually no wind or weather because of its slow rotation

Front 165

T or F
Venus lacks glaciers, rivers, rain, or strong winds.

Back 165

True

Front 166

T or F
Venus doesn't show evidence of Earth-like plate tectonics.

Back 166

True

Front 167

What is unique about the Venus impact craters?

Back 167

They are distributed evenly over the entire planet, suggesting that the surface is about the same age everywhere.

Front 168

What is thought to be the age of the Venus surface?

Back 168

750 million years old

Front 169

What is thought to have occurred on the Venus surface 750 million years ago?

Back 169

The surface was "repaved"

Front 170

What is the plausible explanation for Venus lacking tectonics?

Back 170

Venus's lithosphere resists fracturing into plates because it is thicker and stronger than Earth's lithosphere.

Front 171

Why does Venus have such high temperatures?

Back 171

Venus greenhouse effect

Front 172

Why does Venus have such a strong greenhouse effect?

Back 172

the huge amount of carbon dioxide

Front 173

How much carbon dioxide does Venus have?

Back 173

over 200,000 times that in Earth's atmosphere

Front 174

What is the name given to rocks that are rich in carbon and oxygen?

Back 174

Carbonate rock

Front 175

Name an example of a carbonate rock?

Back 175

limestone

Front 176

Where does most of the carbon dioxide on the Earth reside?

Back 176

inside rocks, about 170,000 times more in rocks as in its atmosphere

Front 177

What would happen if all of the Earth's carbon dioxide were in its atmosphere rather than in rocks?

Back 177

We would be as hot as Venus is

Front 178

T or F
Venus has water in its atmosphere.

Back 178

True, a very little amount

Front 179

Why does Venus retain carbon dioxide in its atmosphere?

Back 179

it lacks oceans to dissolve the carbon dioxide and lock it away in rock

Front 180

T or F
Water vapor is a greenhouse gas.

Back 180

True

Front 181

What is the term given to the loops of water vapor adding to the atmosphere meaning higher temperature and even more water vapor?

Back 181

Runaway Greenhouse effect

Front 182

What is thought to be the explanation for why Venus is so hottter than Earth?

Back 182

The greater intensity of sunlight made it just enough warmer that oceans either never formed or soon evaporated.

Front 183

Why did carbon dioxide accumulate in the Venus atmosphere?

Back 183

Without oceans to dissolve carbon dioxide and carbonate rock, carbon dioxide accumulated in the atmosphere, leading to runaway green house effect

Front 184

What are the 4 unique features that turn out to be particularly important to life on Earth?

Back 184

1. surface liquid water
2. atmospheric oxygen
e. Plate tectonics
4. climate stability

Front 185

T or F
Earth is the only planet on which temperature and pressure conditions allow surface water to be stable as a liquid

Back 185

True

Front 186

T or F
Earth is the only planet with significant oxygen in its atmosphere and an ozone layer.

Back 186

True

Front 187

T or F
Earth is the only planet with a surface shaped largely by this distinctive type of tectonics

Back 187

True

Front 188

T or F
Earth has a climate that has remained relatively stable throughout its history.

Back 188

True

Front 189

What does life as we know it in order to survive?

Back 189

Water,
and animal life needs oxygen in atmosphere.

Front 190

What is the origin of Earth's water?

Back 190

Water vapor outgassed from volcanoes rained down on the surface to make the oceans and neither froze nor evaporated thanks to our moderate greenhouse effect and distance from the Sun

Front 191

T or F
Oxygen is a product of outgassing.

Back 191

FALSE
Oxygen is not a product of outassing.

Front 192

T or F
No geological process can explain how oxygen came to make up such a large fraction of Earth's atmosphere.

Back 192

True

Front 193

What gives rise to the reddish color of the Earth's surface area?

Back 193

Reactions between oxygen and surface materials

Front 194

What explains where Earth's oxygen comes from?

Back 194

Photosynthesis takes in CO2, and release O2. The carbon becomes incorporated into living tissues

Front 195

What explains why oxygen concentration of Earth remains relatively steady

Back 195

Photosynthetic organisms return oxygen to the atmosphere in approximate balance with the rate at which animals and chemical reactions consume it.

Front 196

T or F
Climate and plate tectonics are closely linked

Back 196

True

Front 197

What geological feature of the EArth acts like a giant conveyor belt for the Earth's lithosphere?

Back 197

Plate tectonics

Front 198

What is the term for the mantle material that rises upward and erupts to the surface along mid-ocean ridges, becoming new crust for the seafloor?

Back 198

Seafloor crust

Front 199

What is the term for the movement and recycling of the seafloor crust that takes tens of millions of years to complete?

Back 199

Subduction

Front 200

Where does subduction occurr?

Back 200

Where seafloor plates run into continental plates.

Front 201

Why do so many volcanoes tend to be found along the edges of continents?

Back 201

The molten rock erupts from volcanoes over the subduction zones

Front 202

Is the continental crust emerging from these landlocked volcanoes lower or higher in density than seafloor crust?

Back 202

Continental crust is lower in density

Front 203

Why do continents rose above the seafloor?

Back 203

Because the continental crust is lower in density than the seafloor crust

Front 204

T or F
Seafloor crust is never more than a couple of hundred millions years old.

Back 204

True

Front 205

Where do Earthquakes tend to occur?

Back 205

when 2 plates get "stuck" against one another and then lurch violently when the pressure builds to the breaking point

Front 206

What is the key to the Earth's stable climate:

Back 206

Earth has always kept just enough carbon dioxide in its atmosphere to keep the temperature in a range suitable for liquid water and life

Front 207

What is the term for the mechanism by which Earth self-regulates its temperature?

Back 207

Carbon dioxide cycle or
CO2 cycle for short

Front 208

What are the 5 steps in the CO2 cycle:

Back 208

1. atmospheric CO2 dissolves in rainwater, creating a mild acid
2. mildly acidic rainfall erodes rocks on Earth's continents, and rivers carry the broken-down minerals to the oceans
3. in oceans, the eroded minerals combine with dissolved CO2 and fall to the ocean floor, making carbonate rocks such as limestone
4. over millions of years, the conveyor belt of plate tectonics carries the carbonate rocks to subduction zones and subduction carries them down into the mantle
5. as they are pushed deeper into the mantle, some of the subducted carbonate rock melts and releases its carbon dioxide, which then outagses back inot the atmosphere through volcanoes

Front 209

What acts as a long-term thermostat for Earth?

Back 209

CO2 cycle

Front 210

What happens to CO2 if the atmospheric temperature rises?

Back 210

More CO2 is removed

Front 211

What happens when CO2 in atmosphere increases?

Back 211

It strengthens the greenhouse effect

Front 212

What is the term for "natural" cycles that have been linked to small, cyclical changes in Earth's exis tilt and other characteristics of Earth's rotation and orbit?

Back 212

Milandovitch cyles

Front 213

T or F
Global avg temperatures have risen @ 0.8C in the past century

Back 213

True

Front 214

What is the term applied to what appears to by an unnatural warming of the globe?

Back 214

Global warming

Front 215

List the 3 facts about global warming we know:

Back 215

1. fossil fuels & other activity is increasing the amounts of green house gases in the atmosphere
2. a continually rising concentration of greenhouse gases would eventually make our planet warm up
3. computer models of the climate indicate that global temps are increasing in a manner consistent with what we would expect if human activity is the cause

Front 216

What is happening to the EArth's polar regions?

Back 216

They are warming causing ice to melt

Front 217

What will happen to the elevation of the oceans if the temp continues to rise?

Back 217

The oceans will warm

Front 218

What happens to salt content in oceans if polar ice melts?

Back 218

The ocean currents may alter

Front 219

What do warmer oceans produce weather wise?

Back 219

They produce more hurricanes and more severe blizzards

Front 220

What is happening to the great snows of Mt. Kilimanjaro?

Back 220

The glaciers are rapidly retreating and may be gone completely in the next decade.

Front 221

What makes Earth habitable?

Back 221

1. Its size
2. Its distance from the Sun