Earth’s Processes: Climate Change (Unit 3)

Question 1

What is coal’s relationship with carbon?

Answer 1

Coal is a sedimentary rock made mostly of carbon that is burned to generate electricity

Question 2

Where is carbon found? How do plants, such as trees, use it?

Answer 2

The element carbon is found in living things and in all parts of Earth’s systems. It combines with oxygen in the form of carbon dioxide and is taken in by plants to form compounds that make their structure. The trunk of a tree is made mostly of carbon taken from the atmosphere as carbon dioxide.

Question 3

What happens to the carbon inside plants or animals that eat plants when humans eat and metabolize them? How much carbon, by mass, makes up the human body? Where is carbon absorbed? Does the total amount of carbon ever change?

Answer 3

When people eat plants, or eat animals that have eaten plants, the carbon is rearranged to form molecules such as proteins and DNA. Approximately 18 percent of the human body is carbon. Carbon is also dissolved in the oceans and in the geosphere in rocks, such as limestone and coal. As carbon moves between Earth’s systems, the total amount never changes.

Question 4

True or False: Carbon forms the backbone of molecules, such as glucose, amino acids, DNA, and ATP

Answer 4

True

Question 5

How does carbon recycle through the biosphere?

Answer 5

Carbon recycles through the biosphere by changing forms

Question 6

How much carbon dioxide makes up our atmosphere?

Answer 6

0.04%

Question 7

Why do we use fossil fuels for quicker carbon transfer?

Answer 7

When people breathe in and out, they cycle carbon from their bodies to the atmosphere very quickly. Cycling carbon from living organisms to the geosphere can take millions of years. People release the carbon from fossil fuels to the atmosphere quickly for transportation and energy.

Question 8

Fossil Fuel Definition

Answer 8

A substance formed from the remains of once-living organisms used by people for energy

Question 9

How does carbon enter the atmosphere?

Answer 9

Carbon enters the atmosphere through decay of dead organisms, fires, respiration, and burning of fossil fuels, such as gasoline, coal, and methane. Fossil fuels store vast amounts of carbon, and when they are burned, this carbon is released into the atmosphere.

Question 10

What is the relationship between carbon dioxide in the atmosphere and oceans?

Answer 10

Carbon dioxide gas in the atmosphere is in equilibrium with dissolved carbon dioxide in the ocean, so some of it enters the ocean and becomes incorporated into organisms there. Matter from these organisms can settle on the ocean floor and become rock. Green plants also take in carbon dioxide through photosynthesis.

Question 11

What is evidence for how humans have tipped the balance of the carbon cycle?

Answer 11

If you add the movement of carbon into and out of the atmosphere, you can calculate this net increase per year. Reworking this calculation without the contribution by humans burning fossil fuels, you will find that there is a small net decrease of carbon dioxide in the atmosphere. Using this model, you can see that human activity of extracting fossil fuels and burning them for energy has tipped the balance of the carbon cycle.

Question 12

Respiration Definition

Answer 12

The process by which organisms obtain energy by taking in oxygen and releasing carbon dioxide

Question 13

Equilibrium Definition

Answer 13

A state of balance between opposing processes

Question 14

How many bonds can carbon make?

Answer 14

4

Question 15

How do plants use carbon dioxide to maintain structure and grow? (1st part of carbon cycle in biosphere)

Answer 15

Plants take molecular carbon dioxide from the atmosphere and fix the carbon from it to form different molecules, such as glucose, amino acids, and ATP, in the plant. When plants grow, the mass for it comes from the air, allowing it to keep growing

Question 16

What happens when we metabolize the carbon in glucose from plants? (2nd part of carbon cycle in biosphere)

Answer 16

When we metabolize the carbon in glucose from plants, we release it as carbon dioxide, creating a cycle

Question 17

True or False: all organic molecules contain carbon

Answer 17

True

Question 18

(Remember) Carbon Cycle in the Biosphere: atmospheric carbon dioxide —> plants —> organic molecules —> human metabolization —> release of carbon dioxide from humans in respiration

Answer 18

Carbon Cycle in the Biosphere: atmospheric carbon dioxide —> plants —> organic molecules —> human metabolization —> release of carbon dioxide from humans in respiration

Question 19

True or False: Carbon is the chemical backbone of all life on Earth

Answer 19

True

Question 20

True or False: All of the carbon we have on Earth is the same amount we have always had

Answer 20

True

Question 21

Where is most carbon stored? How do these places of storage influence the carbon cycle?

Answer 21

Most carbon is stored in rocks and sediments, while the rest is stored in the ocean, atmosphere, and living organisms. These are reservoirs or sinks through which carbon cycles

Question 22

What are the six stores of carbon in order?

Answer 22

1. Atmosphere
2. Ocean
3. Plants and Animals
4. Soil and Organic Matter
5. Fossil Fuels
6. Sedimentary Rock

Question 23

What are the characteristics of the first of the six carbon stores, the atmosphere?

Answer 23

Most carbon in the atmosphere is in the form of carbon dioxide.

Question 24

What are the characteristics of the second of six carbon stores, the ocean? (Carbon Exchange)

Answer 24

The carbon exchange is the trade of carbon between the oceans and the atmosphere. Oceans dissolve carbon dioxide from the atmosphere. Marine plants use it for photosynthesis and release some back into the atmosphere through respiration. Marine animals use carbon in the ocean to make calcium carbonate—a component of shells and skeletons.

Question 25

What are the characteristics of the third of six carbon stores, plants and animals?

Answer 25

Plants use carbon dioxide during photosynthesis. They also release a little carbon dioxide when they respire. Animals get their carbon from the vegetation or other animals they eat. They also release carbon dioxide when they respire. When plants are burned, carbon dioxide is released into the air.

Question 26

What are the characteristics of the fourth of six carbon stores, soil and organic matter?

Answer 26

When plants and animals die, their carbon-rich remains decay. Decomposers release carbon dioxide into the air as they respire.

Question 27

What are the characteristics of the fifth of six carbon stores, fossil fuels?

Answer 27

Fossil fuels, formed millions of years ago from plants and animals, are carbon-rich. Carbon dioxide is released when humans burn these fuels.

Question 28

What are the characteristics of the sixth and last carbon store, sedimentary rock?

Answer 28

Billions of tons of carbon are stored in ocean sediment and sedimentary rocks. The carbon is released into the atmosphere through volcanic eruptions.

Question 29

What are the two main ways carbon dioxide is absorbed?

Answer 29

The two main ways carbon dioxide is absorbed is through plants and oceans

Question 30

Why is Ireland approximately 40°F warmer than Newfoundland, despite being on the same latitude?

Answer 30

Ireland is about 40°F warmer than Newfoundland in winter because the Gulf Stream current is near its West Coast. Westerly winds passing over the current hit Ireland, allowing some warm-climate plants to flourish

Question 31

How much has Earth’s average temperature risen since 1880? Why is this alarming, considering the last 11,000 years of Earth’s history?

Answer 31

Earth’s average temperature has risen almost 1.11°C (2°F) since 1880, when scientists started keeping this record. That is a significant rise, given that the average global temperature is higher now than it has been for most of the last 11,000 years.

Question 32

Greenhouse Gas Definition

Answer 32

Gas in the atmosphere that traps Earth’s heat

Question 33

Since 1955, how much thermal energy has the ocean been storing? What are the effects of this storage?

Answer 33

Since 1955, the oceans have absorbed and stored about 90 percent of that excess heat, with striking results. There has been a rise in sea level due to thermal expansion of the ocean. Land-based glaciers and ice sheets are also melting at an accelerated rate, pouring meltwater into the oceans. The effects of rising sea levels include more coastal flooding and the slow submerging of low-lying islands.

Question 34

True or False: An important impact of oceans on climate change has been to limit its harmful effects

Answer 34

True

Question 35

In 2019, what did scientists report about the alarming amount of carbon dioxide in the atmosphere?

Answer 35

In 2019, scientists reported that the amount of CO2 in the atmosphere today is higher than it has ever been. It is also rising much faster than at any time on record.

Question 36

How much of the carbon dioxide produced by human activities does the ocean absorb?

Answer 36

One-fourth

Question 37

How is excess carbon changing the chemistry of ocean water in a process known as ocean acidification? What are the effects of this change?

Answer 37

Scientists have found that the excess carbon is slowly changing the chemistry of ocean water. The ocean is becoming more acidic. The process is known as ocean acidification. The increasing acidity of ocean water threatens the survival of some marine species such as corals. They have difficulty making shells in the increasingly acidic water. Scientists have also discovered that the ocean’s ability to absorb CO2 decreases with rising temperatures.

Question 38

Ocean Acidification Definition

Answer 38

The increase in acidity of the ocean due to added carbon dioxide

Question 39

What factors form gyres?

Answer 39

Surface winds drive the currents, and they are deflected by Earth’s rotation and the shape of ocean basins into huge gyres.

Question 40

Gyre Definition

Answer 40

a system of rotating ocean currents

Question 41

True or False: Like winds, currents help to equalize the distribution of Earth’s heat.

Answer 41

True

Question 42

How could climate change’s influence on currents influence the climate of places on Earth?

Answer 42

By changing the strength or course of currents, global warming could trigger drastic climate changes. Recall how westerly winds crossing the warm Gulf Stream moderate climate in Western Europe. Without the influence of the Gulf Stream, Western Europe would be about 5°C (9°F) colder than it is now. Without the cool Canary Current to moderate the influence of the nearby Sahara Desert, the Canary Islands would have a hotter climate.

Question 43

What effects have global warming had on hurricanes and weather?

Answer 43

Increased oceanic surface temperatures, due in part to global warming, have contributed to the recent increase in hurricane activity. The oceans cover more than 70 percent of Earth’s surface, so as they warm, they greatly impact weather and climate.

Question 44

Ocean Acidification Remember: The CO2 dissolves, bonds with the water, H2O, and creates carbonic acid, H2CO3. The acidic ocean waters can hurt marine animals by dissolving calcium carbonate-based shells and exoskeletons.

Answer 44

The CO2 dissolves, bonds with the water, H2O, and creates carbonic acid, H2CO3. The acidic ocean waters can hurt marine animals by dissolving calcium carbonate-based shells and exoskeletons.

Question 45

Global Conveyor Belt Definition

Answer 45

A system of currents that transfers heat between the poles and the equator

Question 46

What happened to the weather in the Northern Hemisphere when the Gulf Stream and Atlantic Current slowed, showing the impact of global warming?

Answer 46

There have been times in the past when the warm Gulf Stream and Atlantic Current slowed and didn’t move as much warm water north as part of the cycle. At these times, the northern hemisphere cooled down, and there were stronger North Atlantic storms. As Earth warms and the oceans absorb more heat, understanding the effect these currents have on climate will be increasingly important.

Question 47

What factors are helpful in studying the history of Earth’s climate?

Answer 47

To study the history of Earth’s climate, it is helpful to measure global average temperature and concentration of gases over Earth as a whole

Question 48

True or False: Scientists have evidence that Earth’s climate has gone through cycles

Answer 48

True

Question 49

How is The Great Oxygenation Event, concerning cyanobacteria, an example of natural climate change (atmospheric composition)?

Answer 49

Natural causes of climate change can be traced back to the earliest form of life on Earth. Aquatic bacteria known as cyanobacteria developed the ability to photosynthesize roughly 2.3 billion years ago, allowing them to add oxygen into the air. This addition of oxygen gas occurred over the course of hundreds of millions of years, as part of what is known as The Great Oxygenation Event

Question 50

What was the effect of The Great Oxygenation Event?

Answer 50

Earth’s atmosphere had been rich in methane, a greenhouse gas. As oxygen displaced the methane in the atmosphere, Earth’s temperature dropped, leading to the longest glaciation period on record. The addition of oxygen also killed off most other life forms at the time, which were mainly anaerobic bacteria. This set the stage for the evolution of oxygen-breathing life forms

Question 51

Note: What does oxygen leading to glaciation tell you?

Answer 51

That oxygen reflects more of the sun’s energy

Question 52

True or False: The Great Oxygenation Event provides a good example of feedback, causing other changes in a system

Answer 52

True

Question 53

Feedback Definition

Answer 53

Ability of change in a system to lead to further changes

Question 54

How have ice cores provided evidence for Earth’s climatic cycles?

Answer 54

Evidence for Earth’s climatic cycles are found in ice cores–samples of ancient ice drilled from deep inside glaciers. Air bubbles and particles trapped in the ice provide evidence of the conditions of the atmosphere long ago

Question 55

How has rust in sedimentary rock contributed to the study of Earth’s climatic cycles?

Answer 55

As oxygen accumulated in the oceans, it bonded with iron in the water, creating rust. This rust fell to the ocean floor, leaving evidence that scientists can study in sedimentary rocks

Question 56

What happened after the oceans were saturated with oxygen?

Answer 56

The oceans were eventually saturated with oxygen which then began to accumulate in the atmosphere

Question 57

How are the Milankovitch Cycles another example of natural climate change?

Answer 57

The way that Earth travels through space has provided another natural cause of climate change. Earth’s orbit changes from nearly circular to slightly oval on a 100,000-year cycle (eccentricity). Earth rotates on its axis at a tilt, which varies between a 22- and 24-degree tilt every 41,000 years (obliquity). The axis also wobbles like a spinning toy top, toward and away from the sun, about every 26,000 years (precession).

Question 58

What is the impact of the Milankovitch Cycles on climate?

Answer 58

Eccentricity, Obliquity, and Precession, known as the Milankovitch Cycles, have an impact on seasons and periodic cycles of change in temperature over a long period of time

Question 59

What do scientists believe explain Earth’s glacial periods and interglacial periods? What are the characteristics of glacial periods and interglacial periods?

Answer 59

Scientists believe that the Milankovitch cycles explain why Earth’s climate has fluctuated between glacial periods and interglacial periods. Earth’s most recent glacial period was between 120,000 and 11,500 years ago. These fluctuations in temperature can be seen by looking at graphs of the Vostok ice core data shown above. The periods of low temperature led to higher rates of glacier formation, which meant that sea levels were lower. The interglacial periods resulted in the melting of glaciers and a rise in sea levels. Colder water is able to absorb more carbon dioxide, meaning that carbon dioxide levels in the atmosphere were lower during glacial periods and higher during interglacial periods. In turn, atmospheric carbon dioxide enhances the Earth’s greenhouse effect. This interaction between Earth’s temperature, atmospheric carbon dioxide levels, and sea level provides another example of a feedback cycle.

Question 60

Glacial Period Definition

Answer 60

A period in Earth’s history marked by prolonged low global temperatures

Question 61

Interglacial Period

Answer 61

A period in Earth’s history marked by prolonged high global temperatures

Question 62

Through studying the history of Earth’s climate, how is it evident that the changes in the past decades are not natural? (parts per million)

Answer 62

It is clear that Earth’s climate has changed due to natural causes throughout its history. The changes in Earth’s climate in recent decades, however, are unprecedented in proportion and scale. When scientists categorize the changes in Earth’s climate over time, it becomes evident that the recent changes in Earth’s carbon dioxide and temperature are of a scale not previously recorded. The recent spike in carbon dioxide began in the late nineteenth century, when human emissions of carbon dioxide increased due to the use of coal-burning combustion engines and later, gasoline-fueled cars. While carbon dioxide levels in Earth’s atmosphere fluctuated between 180 and 280 parts per million over the past 800,000 years, levels are now approaching 420 parts per million. Scientists know from past evidence and understanding of feedback cycles that the changes in carbon dioxide are causing a cascade of changes throughout Earth’s systems, including increased global temperature and sea level, and impacts on many organisms as a result.

Question 63

Scale Definition

Answer 63

A system of measuring and describing quantities

Question 64

How is the lack of snow evidence for climate change?

Answer 64

Across the country, there is less snowpack since 1930, and a higher chance of rain falling and ruining the snow. Some places have had to shorten cross-country skiing routes, and lots of ski resorts have to make snow more often.

Question 65

Remember: Scientists can use carbon isotope markers to figure out where carbon dioxide comes from. The amount coming from burning fossil fuels has been going up.

Answer 65

Scientists can use carbon isotope markers to figure out where carbon dioxide comes from. The amount coming from burning fossil fuels has been going up.

Question 66

True or False: Five of the hottest years on record have happened since 2011

Answer 66

False; 2010

Question 67

How much has Earth’s average surface temperature risen since the late 19th century?

Answer 67

Starting in the late nineteenth century, when the Industrial Revolution swung into full force, Earth’s average surface temperature has risen about 0.9°C (1.62°F)

Question 68

Global Warming Definition

Answer 68

The gradual increase in the overall temperature of Earth’s atmosphere

Question 69

What tools do scientists use to measure climate change?

Answer 69

Measuring climate change is much more complicated than just measuring increasing air temperatures. Scientists use many different scientific tools and tests to measure how Earth’s climate has changed throughout history. There are several measurements scientists use to study climate change:

• • carbon dioxide levels
• • air temperature
• • the amount of sea ice at the poles
• • ocean temperatures
• • sea levels
• • glacier size

Question 70

Climate Change Definition

Answer 70

The long-term change of temperature and normal weather patterns in a place

Question 71

How does the width of tree rings provide evidence for the climatic conditions of Earth’s past?

Answer 71

Scientists know what climate conditions thousands of years ago were like. Things such as tree rings hold information about past climates. A tree’s rings grow wider in warm, wet weather, and they stay thinner in cold, dry weather. Studying the size of the rings, therefore, gives scientists information about rainfall and temperature at the time each ring was formed.

Question 72

True or False: Each tree ring indicates a year of growth

Answer 72

true

Question 73

How can the leftover shells of small animals like foraminifera help scientists estimate the ocean’s temperature long ago?

Answer 73

Scientists can even look at the leftover shells of small animals like foraminifera. The percentage of chemical isotopes found in these shells allows scientists to estimate the ocean’s temperature millions of years ago when the animals lived.

Question 74

How do fossilized pollen grains help identify the climate at a certain point in Earth’s history?

Answer 74

Fossilized pollen grains can also contribute to the record since knowing what kind of plants grew at a particular time indicates what the climate was like.

Question 75

Glacial Retreat Definition

Answer 75

The moving up of the end of a glacier so that it does not extend as far down-valley as it once did

Question 76

Remember: Scientists monitor surface temperatures around the world and air temperatures in different parts of the atmosphere. Ocean temperatures and how they have changed over time also provide important data about climate change. Ocean
temperatures greatly influence weather and, therefore, climate.

Answer 76

Scientists monitor surface temperatures around the world and air temperatures in different parts of the atmosphere. Ocean temperatures and how they have changed over time also provide important data about climate change. Ocean
temperatures greatly influence weather and, therefore, climate.

Question 77

What is Argo? What do they do?

Answer 77

An international effort called Argo measures ocean temperatures. About 3,200 floats measure ocean temperature and salinity, which changes based on freshwater input

Question 78

How are satellites used in measuring climate change?

Answer 78

Satellite images are used to study climate change from space. Images taken at different times allow scientists to see and measure how features change, such as:

• a decrease in spring snow cover in the Northern
Hemisphere

• a decrease in the extent and thickness of Arctic Sea Ice
• glacial retreat

• a decrease in mass of the Greenland and Antarctic ice
sheets

This loss of snow and ice contributes to sea level rise. In the last century, global sea level rose 20 cm (8 in.). The rate at which it is currently rising is alarmingly twice as fast as the last century

Question 79

Why are polar bears considered a threatened species?

Answer 79

Polar bears are considered a threatened species since their ice is melting

Question 80

How is climate change impacting all of Earth’s spheres? Which sphere is most involved in climate change?

Answer 80

All of Earth’s spheres are affected by climate change, but the atmosphere is most involved. In the atmosphere, different gas molecules are constantly moving, reacting with each other and changing states. The concentrations of these gases remained relatively stable over a long period of time. But humans have added gases to the atmosphere that have led to changes in other Earth systems and caused climate change. The composition and energy changes of the atmosphere seem small, but they can upset Earth’s natural balance and have a big impact on all of Earth’s spheres.

Question 81

What are carbon dioxide, water vapor, and methane examples of?

Answer 81

Greenhouse gases

Question 82

What is one way greenhouse gases are added to the atmosphere naturally? What is the predominant way they are added?

Answer 82

Some greenhouse gases are added to the atmosphere by natural occurrences, such as volcanic eruptions. However, most greenhouse gases are added by human action.

Question 83

Greenhouse Gas Definition

Answer 83

an atmospheric gas that absorbs and reradiates the sun’s energy

Question 84

What was the concentration of carbon dioxide in the atmosphere during 2017? How has this affected Earth’s average surface temperature?

Answer 84

The current concentration of carbon dioxide in the atmosphere is approximately 409 parts per million (ppm), which has led Earth’s average surface temperature to increase 0.8°C (1.4°F) since 1880

Question 85

What does the Clean Air Act require states to do?

Answer 85

The Clean Air Act requires most states to conduct vehicle inspections to identify motor vehicles that emit excessive levels of air pollutants.

Question 86

In discussions of climate change, the average global temperature is often brought up, but does that mean each temperature of each place on Earth is raised by that amount?

Answer 86

In discussions of climate change, the average global surface temperature is often cited. This does not mean that the temperature is raised that amount everywhere on Earth. In fact, increases in temperature vary widely from place to place. Higher temperatures may sound like a good thing if you live somewhere cold, but temperature increases affect the climate in different ways.

Question 87

How is climate change affecting different climates?

Answer 87

Climate change can affect the amount of precipitation. This map shows precipitation for February, 2018 compared to an average for February during the period from 1981 to 2010. The white or very light areas indicate very little change compared to historical data, brown shows decreased precipitation, and green shows increased precipitation. Increased temperatures and increased water vapor in the atmosphere also contribute to an increase in the occurrence and the severity of storms in some places. In other regions, climate change results in less precipitation and dry conditions. Compiling data over several months and years and comparing it to historical data indicate rates of change. The patterns that emerge can also help in developing predictive models.

Question 88

What is the biggest affect of climate change in Antarctica? How does this affect the world’s temperature?

Answer 88

The biggest effect of climate change in Antarctica is the rise in global temperature. The average temperature at the Antarctic Peninsula, which extends into the ocean toward the southern tip of South America, has risen 3°C over the past 50 years. This may seem like a small increase, but the rate is five times higher than the average rate on Earth. The water melting from the land ice on the peninsula raises sea levels. Less ice means exposed land absorbs more solar energy, raising surface temperatures. It absorbs almost all the solar radiation that hits it, so when ice melts, global temperatures rise, which affects climates around the world.

Question 89

What is the flooding situation in Wilmington, North Carolina?

Answer 89

In the last few years, this region has seen the largest increase in flooding since 1950. Wilmington has flooded 49 days per year in the 2010s, compared to one or two days per year in the 1950s.

Question 90

How is the flooding situation in Wilmington, North Carolina related to Antarctica?

Answer 90

As Antarctic ice melts and the temperatures increase there, more water enters the atmosphere, contributing to the increased intensity of storms worldwide. In addition, sea level is rising at a rate of 3.3 mm/yr. The combination of severe storms and rising sea levels has caused increased flooding, especially in coastal areas such as North Carolina.

Question 91

True or False: the atmosphere is transparent to light of visible and near-infrared wavelengths, as well as a car

Answer 91

True

Question 92

Is the glass in cars transparent to far-infrared wavelengths?

Answer 92

No

Question 93

Temperatures near the surface of the planet stay at a fairly narrow range. What does this show about the balance in the troposphere?

Answer 93

Temperatures near the surface of the planet stay within a fairly narrow range. This stability indicates a balance between energy entering and leaving the troposphere, the layer of the atmosphere at the planet’s surface.

Question 94

What is the phenomenon known as the greenhouse effect? How does it work in our atmosphere?

Answer 94

Some gases in the atmosphere absorb the far infrared wavelengths radiated upward by Earth’s surface and reradiate them in all directions. Some of this retained heat energy is absorbed by other gas molecules and reradiated again. This cycle warms the atmosphere near Earth’s surface. Because this is similar to the way a greenhouse traps energy near the surface, the term greenhouse effect was coined to describe the phenomenon.

Question 95

Greenhouse Effect Definition

Answer 95

Gases near Earth’s surface absorbing and remitting heat

Question 96

Is there any physical barrier preventing the warm air from rising? What is the atmosphere’s transparency when it comes to far-infrared radiation?

Answer 96

In the greenhouse effect, there is no physical barrier preventing the warm air from rising. Just as glass is not transparent to far infrared wavelengths of light, the atmosphere is not fully transparent to far infrared wavelengths. Instead, the infrared energy radiated upward by Earth’s surface is absorbed by some gases in the atmosphere, called greenhouse gases, and then reradiated into the atmosphere in all directions. This keeps the heat near Earth’s surface, raising the temperature.

Question 97

What are carbon sinks?

Answer 97

Systems that take carbon from the atmosphere

Question 98

How is the greenhouse gas methane produced? What percentage of greenhouse gases in the atmosphere does methane account for?

Answer 98

Methane is produced from landfills, livestock, agricultural practices such as growing rice, and the production and transportation of fossil fuels. Methane accounts for 10% of the greenhouse gases in the atmosphere

Question 99

How many times more efficient Is methane at trapping heat compared to carbon?

Answer 99

21 times

Question 100

What is the greenhouse gas nitrous oxide and how is it produced naturally and industrially? How many times more efficient is it at trapping heat compared to carbon dioxide?

Answer 100

Nitrous oxide is a natural byproduct of the nitrogen cycle. The nitrogen cycle describes the way that nitrogen is circulated among the atmosphere, plants, animals, and microorganisms that live in soil and water. However, nitrous oxide also comes from industrial activities such as wastewater treatment. Nitrous oxide can trap as much as 298 times the amount of the heat that carbon dioxide can.

Question 101

What is the source of the greenhouse gas fluorinated gases? How many times more efficient is it at trapping heat compared to carbon dioxide?

Answer 101

Fluorinated gases have no natural source and only come from products such as refrigerators, circuit breakers, air conditioners, and aerosol cans. Fluorinated gases can retain the equivalent of 10,000 times the amount of heat compared to carbon dioxide

Question 102

What is the concentration of fluorinated gases? What work is being done to limit their usage?

Answer 102

Fluorinated gases are present only in very small concentrations and work is being done to regulate their production

Question 103

What are the characteristics of the greenhouse gas water vapor?

Answer 103

Water vapor depends on the temperature of the atmosphere. As the air becomes warmer, it can hold more moisture. Water vapor is not increased directly by human activity, but instead as human activity warms the atmosphere.

Question 104

What are the characteristics of the greenhouse gas carbon dioxide? How long will it remain?

Answer 104

Carbon dioxide is exchanged through the atmosphere via photosynthesis, respiration, organic decay, and the burning of organic material. In the past two hundred years, the burning of organic material has greatly increased, increasing the concentration of carbon dioxide in the atmosphere by 30%. Carbon dioxide that is added to the atmosphere will remain for hundreds of years.

Question 105

How do methane and carbon dioxide compare?

Answer 105

Methane is a stronger absorber and emitter of infrared radiation than carbon dioxide, but it is present in the atmosphere in much smaller amounts

Question 106

How long will methane remain in the atmosphere?

Answer 106

For around a decade

Question 107

True or False: methane can come from petroleum and natural gas production

Answer 107

True

Question 108

What is causing the concentration of nitrous oxide to increase?

Answer 108

Nitrous oxide has increased in concentration due to agriculture and the use of fertilizers. It is also produced in combustion.

Question 109

Is stratospheric ozone a greenhouse gas? Why or why not?

Answer 109

Stratospheric ozone is not considered a greenhouse gas because it is not in the troposphere. Pollution can cause reactions that produce ozone closer to Earth’s surface.

Question 110

How long do fluorinated gases, such as chlorofluorocarbons, remain in the atmosphere?

Answer 110

For hundreds of thousands of years

Question 111

What Makes a Gas Molecule a Greenhouse Gas?

Answer 111

It has to do with molecular vibrations and interactions with infrared radiation.

Question 112

What happens when two-atom gases, such as nitrogen and oxygen, absorb energy? Why does their vibration make them transparent to infrared radiation?

Answer 112

Nitrogen and oxygen, the most common constituents of the atmosphere, are molecules that are formed of two atoms: N2 and O2. When such a molecule absorbs energy, it vibrates as the two atoms move toward each other and apart. Molecules with two atoms take one shape and have one mode of vibration. As a result of this simpler vibration, oxygen, nitrogen, and similar gases are transparent to infrared radiation.

Question 113

What happens when greenhouse gases, which have three atoms, absorb infrared energy? How does their vibration allow them to interact more with infrared radiation!

Answer 113

Greenhouse gases such as water vapor, methane, carbon dioxide, and chlorofluorocarbons are formed of three or more atoms. They can take multiple shapes and have more modes of vibration, as they bend or stretch. Because of their complexity, they are more likely to interact with infrared radiation and absorb and reradiate it.

Question 114

Remember: actual molecular energy is quantized. That means not all wavelengths of light are absorbed and re-emitted. Instead, greenhouse gas molecules absorb and reradiate only certain energy levels in the infrared range.

Answer 114

Actual molecular energy is quantized. That means not all wavelengths of light are absorbed and re-emitted. Instead, greenhouse gas molecules absorb and reradiate only certain energy levels in the infrared range.

Question 115

What percentage of ozone is in the troposphere? In the stratosphere?

Answer 115

About 10% of Earth’s ozone is in the troposphere. About 90% is in the ozone layer, 10-16 km above Earth’s surface in the stratosphere

Question 116

What is good ozone and what are its benefits? What is bad ozone and what are its effects?

Answer 116

Ozone is a natural and beneficial part of the atmosphere. Ozone in the stratosphere is called good ozone. Here the ozone forms a protective layer that absorbs most of the harmful ultraviolet radiation from the sun. Ozone in the troposphere is called bad ozone. Nitrogen oxides and other harmful gases in the air close to Earth’s surface react with sunlight to produce harmful levels of ozone. The ozone can break down tissue, cause respiratory disease, and increase allergen sensitivity.

Question 117

What are the effects of UV radiation?

Answer 117

Ultraviolet radiation from the sun carries enough energy to damage DNA. Without the ozone layer, sunburn could occur in just a few minutes, and skin cancer rates would be significantly higher.

Question 118

How does the amount of ozone vary with latitude and season?

Answer 118

The amount of ozone varies with latitude and seasons. Intense sunlight produces more ozone near the tropics, but global air circulation transports ozone to other areas. Ozone accumulates at the middle latitudes and the poles. Ozone levels at high latitudes increase in winter and peak in the spring. Levels decrease in summer and fall.

Question 119

What is the ozone hole above Antartica? What was the Montreal Protocol signed in 1987 to stop the hole’s expansion?

Answer 119

In the early 1980s, satellite imaging began to show a depletion of ozone over Antarctica. Seasonal variations modify the effect, but yearly images show a significant increase in this ozone hole. The Arctic also experiences depletion in ozone, but the effect is less extreme there. The ozone hole forms because industry and the use of fossil fuels release harmful gases, primarily those containing chlorine and bromine that react with and destroy ozone in the stratosphere. In 1987, global industries and government signed the Montreal Protocol to stop the production of ozone-depleting gases. Since that time, the ozone hole has slowly begun to decrease.

Question 120

Ozone Hole Definition

Answer 120

Decrease in ozone over Antarctica

Question 121

What is the most common element in industrial polymers?

Answer 121

Carbon

Question 122

Carbon Load Definition

Answer 122

The amount of carbon stored within a living or nonliving reservoir of the carbon cycle

Question 123

How is the increase of carbon dioxide affecting carbon loads?

Answer 123

Due to the increase of carbon dioxide, carbon loads in the global carbon cycle are shifting

Question 124

How does deforestation affect the carbon load in air?

Answer 124

It increase the carbon load in air

Question 125

What transfer of carbon loads do combustion engines cause?

Answer 125

They move the carbon load in fossil fuels to the air

Question 126

True: Global warming is a form of climate change

Answer 126

True

Question 127

What are fluxes in the carbon cycle?

Answer 127

Transfers between living and non-living reservoirs in the carbon cycle are called fluxes

Question 128

How do most power plants produce electricity?

Answer 128

Most power plants produce electricity by burning fossil fuels—generally coal, natural gas, or oil

Question 129

Fossil Fuels Definition

Answer 129

Fuels formed from once-living organisms

Question 130

What is the main source of carbon dioxide?

Answer 130

Combustion of fossil fuels is the main source of carbon dioxide

Question 131

What percentage of the energy used in the United States comes from fossil fuels?

Answer 131

80%

Question 132

How is coal formed? Why are efforts being made to limit its use?

Answer 132

Coal is formed from plants that died in swampy forests, and were then buried by layers of sediment. Over hundreds of millions of years, heat and pressure transformed the buried plants into coal. Because coal produces more carbon dioxide and other harmful pollutants than the other major fossil fuels, there are now efforts to limits its use.

Question 133

How is oil and natural gas formed?

Answer 133

Oil and natural gas both form from the remains of tiny marine plants and animals. After they died, the organisms accumulated at the bottom of seas where sand and mud buried them. As the layers thickened on top of them, intense heat and pressure changed them into petroleum and natural gas. Oil and natural gas can form together or separately. Crude oil as it comes out of the ground is refined into many products, such as gasoline, heating oil, and diesel fuel.

Question 134

What are the fossil fuels oil shale and tar sands? What are their advantages? What are their negatives?

Answer 134

Other fuels include oil shale and tar sands. They produce carbon dioxide when burned, just as other fossil fuels do. The advantage of these “other” fossil fuels is that some of the world’s largest deposits are in the U.S. and Canada. There are environmental challenges of using these fossil fuels. Extracting and processing oil shale and tar sands require large quantities of freshwater and energy and produce toxic substances.

Question 135

True or False: the greenhouse gases in Earth’s atmosphere keep the planet warm enough to support life

Answer 135

True

Question 136

At what temperature do greenhouse gases keep the earth at?

Answer 136

The greenhouse gases keep the planet’s average temperature at about 15.6°C (60°F). Without these gases, Earth’s average temperature would be near freezing. The way greenhouse gases affect Earth’s temperatures is called the greenhouse effect.

Question 137

Remember: Although greenhouse gases are important, they make up less than one percent of Earth’s atmosphere. Still, they have properties that give them the ability to act as a warming blanket around the planet

Answer 137

Although greenhouse gases are important, they make up less than one percent of Earth’s atmosphere. Still, they have properties that give them the ability to act as a warming blanket around the planet.

Question 138

True or False: ozone is a greenhouse gas

Answer 138

True

Question 139

True or False: in general, greenhouse gases are a natural part of Earth’s atmosphere

Answer 139

True

Question 140

Although water vapor is more abundant than carbon, why does it not have an affect on climate change?

Answer 140

Although water vapor is more abundant than carbon dioxide in the atmosphere, the amount of water vapor remains relatively consistent, so it does not change climate.

Question 141

Out of all the greenhouse gases, which one has the biggest affect on climate change?

Answer 141

Of all greenhouse gases, the effect of the increase of carbon dioxide in the atmosphere is the factor that most influences the greenhouse effect and influences climate change.

Question 142

Deforestation Definition

Answer 142

The removal of large areas of forest

Question 143

What was the concentration of carbon dioxide before the Industrial Revolution? How about now?

Answer 143

Just before the start of the Industrial Revolution the concentration of carbon dioxide in the air was about 280 parts per million (ppm). Today it is more than 400 ppm. This is higher than at any other time in human history. That increase is due mostly to human activity.

Question 144

How did the Keeling Curve graph show that the concentration of carbon dioxide is rising?

Answer 144

The trend became obvious in a graph called the Keeling Curve. The graph was named for climatologist Charles David Keeling. Keeling set up the carbon dioxide monitoring system that produced the data in 1958. He placed instruments to monitor carbon dioxide at a weather station atop Mauna Loa, a dormant volcano. The goal was to obtain background readings of carbon dioxide in the air at a location away from cities that have carbon dioxide sources such as power plants, factories, and motor vehicles. The graph shows a steady increase in atmospheric carbon dioxide between 1958 and today. Keeling’s graph has given scientists strong evidence that carbon dioxide in the atmosphere has been rising along with the increased use of fossil fuels.

Question 145

Why is the line on the Keeling Curve a squiggly line rather than a straight one?

Answer 145

The fluctuations are increases and decreases in the amount of CO2 in the atmosphere. The fluctuations are basically the same year after year, suggesting that something occurs in some seasons that decreases the level of CO2, but that event does not occur in the other seasons. During spring and summer when trees are in full leaf, they absorb carbon dioxide during photosynthesis, bringing the amount in the atmosphere down slightly. During the winter season when many trees do not have leaves and photosynthesis does not take place, the amount of CO2 spikes up slightly.

Question 146

How have fossil fuels changed climate?

Answer 146

Temperature extremes and heat waves are increasingly common. Severe drought and heat have affected the Southwest. Heavy precipitation, including day-long downpours, has caused more frequent river flooding in the Northeast, Northwest, and northern Great Plains. A warmer Earth has also produced more frequent and severe storms such as hurricanes.

Question 147

How is climate change affecting ecosystems?

Answer 147

Climate change affects other ecosystems as well. Shorter and milder winters have affected the distribution of some species. Patterns of bird migration are shifting. Spring leaf and flower bloom dates are now earlier in the season for some species to match milder late-winter temperatures. Stream and lake temperatures have risen, changing aquatic habitats. Forests have suffered more frequent wildfires.

Question 148

How much have methane and nitrous oxide increased in terms of concentration?

Answer 148

Methane and nitrous oxide are increasing too. Nitrous oxide has increased by 50 parts per billion in the past 100 years. Methane has increased by 60 parts per billion in just the past 20 years. These may sound like tiny amounts, but remember, methane is 20 times as potent as CO2 in trapping atmospheric heat and nitrous oxide is 300 times more potent than CO2! All these increases in greenhouse gases have some people wondering when we’ll start seeing the effects of climate change.

Question 149

Paleoclimatology Definition

Answer 149

The study of ancient climates

Question 150

How do farming and industry influence anthropogenic climate disruption?

Answer 150

Farming and industry produce gases that affect the composition of the atmosphere, causing anthropogenic climate disruption

Question 151

Anthropogenic Climate Disruption Definition

Answer 151

Disturbance of the climate caused by human activities

Question 152

What percentage of the infrared heat from the surface do greenhouse gases absorb and radiate back?

Answer 152

90%

Question 153

What type of greenhouse gas is sulfur hexafluoride (SF6)?

Answer 153

A fluorinated gas

Question 154

What percentage of greenhouse gas emissions does the transportation sector produce per year? What does the transportation sector include?

Answer 154

The transportation sector generates the largest percentage of GHGs per year, about 30% of all GHG emissions in the United States. The transportation sector includes cars, trucks, buses, trains, planes, ships, and other vehicles used to transport people and goods. It includes the shipping industry and the aviation industry.

Question 155

In the transportation sector, what is the predominant greenhouse gas that is emitted? What is the main cause of this emission? What other greenhouse gases are part of these emission, but in smaller amounts? What types of vehicles are responsible for half of the greenhouse gas emissions in the transportation sector?

Answer 155

Most of the GHG emissions are carbon dioxide generated by the burning of gasoline and diesel fuels in the engines of vehicles. Smaller amounts of methane and nitrous oxide are also part of the emissions. Half of GHG emissions in transportation are from passenger vehicles, such as cars and SUVs.

Question 156

What percentage of greenhouse gas emissions per year are from producing electricity? What gases are emitted? What percentage of electricity in the United States is produced through the burning of fossil fuels? What percentage of the electricity in the United States did coal account for? What percentage of the total amount of greenhouse gas emissions from producing electricity was coal responsible for?

Answer 156

The production of electricity generates about 28 percent of the GHGs—mainly carbon dioxide, but also methane and nitrous oxide—emitted per year in the United States. About 64 percent of the electricity generated in the U.S. is produced by burning fossil fuels such as coal, petroleum, and natural gas. When it is burned to produce electricity, coal emits the most carbon dioxide of the three main fossil fuels. Coal accounted for about 31 percent of the electricity generated in the U.S., and it emitted 68 percent of the carbon dioxide produced by generating that electricity.

Question 157

What is the Goddard Earth Observing System Chemistry-Climate Model used for?

Answer 157

It is used to forecast climate change

Question 158

What are direct emissions of greenhouse gases?

Answer 158

Direct emissions of GHGs are emissions that are produced at the factory or other facility. Direct emissions come from burning fossil fuels on-site for power or heat, through chemical reactions, and from leaks from equipment or processes.

Question 159

What are indirect emissions?

Answer 159

Indirect emissions of GHGs come from burning fossil fuels off-site to generate electricity that is used on-site at the factory or other facility.

Question 160

In 2017, what percentage of the total greenhouse gas emissions were produced by direct emissions? What is the total percentage of greenhouse gas emissions produced by industry?

Answer 160

In 2017, direct emissions of GHGs by industry made up about 22 percent of all GHGs produced that year in the United States. Add in indirect emissions, and industry is responsible for about 30 percent of GHG emissions.

Question 161

Remember: Globally, about half of all carbon dioxide emissions caused by human activity between 1750 and 2010 were released over the past 40 years.

Answer 161

Globally, about half of all carbon dioxide emissions caused by human activity between 1750 and 2010 were released over the past 40 years.

Question 162

Will the atmosphere ever just stop absorbing carbon?

Answer 162

It’s a common misconception that at some point, Earth’s atmosphere will have absorbed all the carbon dioxide that it can hold, and then no more will be absorbed. In reality, that won’t happen until the entire atmosphere is composed of carbon dioxide. Even the atmosphere of Venus, a planet that has already experienced an out-of-control greenhouse effect, is not yet completely “full” of carbon dioxide. Earth’s surface will become unlivable for humans long before its atmosphere is fully saturated with carbon dioxide.

Question 163

Remember: In the past, industry produced emissions of chemicals called chlorofluorocarbons, which are extremely damaging to the atmosphere and which spurred climate change.

Answer 163

In the past, industry produced emissions of chemicals called chlorofluorocarbons, which are extremely damaging to the atmosphere and which spurred climate change

Question 164

When were chlorofluorocarbons created? What were their effects?

Answer 164

Chlorofluorocarbons (CFCs) are chemicals that were invented in 1928. They contain carbon, chlorine, and fluorine atoms. Various industries used CFCs in many products, including aerosol sprays. During the 1970s and 1980s, scientists discovered that when CFCs were released and traveled to the upper stratosphere, the gases reacted with ozone molecules, breaking the bonds between the oxygen atoms and destroying the molecules.

Question 165

True or False: the different facets of agriculture put GHGs into the atmosphere

Answer 165

True

Question 166

What are ruminants? What percentage of greenhouse gas emissions from agriculture are ruminants responsible for?

Answer 166

Cows and sheep belong to a group of mammals called ruminants. These mammals have four-chambered stomachs that contain methane-producing bacteria. Methane escapes from the animals’ bodies into the atmosphere. In fact, about one-third (33%) of the GHGs emissions from agriculture are methane from ruminants, mainly cattle and dairy cows.

Question 167

What percentage of greenhouse gas emissions from livestock is livestock manure responsible for? What are other agricultural sources of GHGs?

Answer 167

Livestock manure is also a source of GHGs. Some methods of manure treatment and storage produce varying levels of methane and nitrous oxide emissions. Gases released by livestock manure represent about 14 percent of all agriculture GHG emissions. Other agricultural sources of GHGs are methane from rice cultivation and methane and nitrous oxide from burning crops.

Question 168

How can soil management lead to the emission of greenhouse gases? What percentage of greenhouse gas emissions from agriculture is soil management responsible for?

Answer 168

Certain methods of soil management, including the use of both synthetic and organic fertilizers, cause nitrous oxide emissions. Using some irrigation practices and growing crops that fix nitrogen in the soil also release nitrous oxide. GHGs released by soil management cause about half (50%) of all agriculture GHG emissions.

Question 169

What percentage of greenhouse gas emissions worldwide is livestock responsible for?

Answer 169

Livestock is responsible for 18% of greenhouse gas emissions worldwide, which also includes the amount of transporting and feeding them

Question 170

True or False: Global meat production has tripled in the last three decades

Answer 170

True

Question 171

How is the water vapor feedback loop both detrimental and beneficial?

Answer 171

Scientists are not yet sure about the net effect of this feedback loop. It does increase the temperature of the atmosphere, but it also helps decrease the temperature of the atmosphere. How is that so? Well, the increased water vapor condenses into clouds, which reflect the sun’s radiation back into space instead of allowing it to reach Earth’s surface. Scientists seek to take more accurate measurements of atmospheric water vapor to help them better understand the importance of the feedback loop.

Question 172

How does an earlier bloom date show that an earlier spring is one affect of climate change?

Answer 172

According to the U.S. Environmental Protection Agency, the peak bloom date of cherry blossoms in Washington D.C. is now five days earlier than it was about 100 years ago. The warmth of spring comes earlier now, coaxing the trees to flower earlier—just one of the impacts of climate change.

Question 173

How is climate change affecting fish populations?

Answer 173

Outside a certain temperature range, it is difficult for fish to reproduce and find food. As ocean waters warm, some fish populations in warmer waters have declined or have shifted their range poleward. Fish that thrive in cooler waters have moved poleward as well, to waters still cool enough for them. Cold-water fish like salmon are finding it more difficult to survive in warmer waters of some rivers in the Pacific Northwest.

Question 174

How has an earlier spring influenced plant and bird populations?

Answer 174

Studies show leaf and bloom dates across the northern hemisphere are now earlier due to warmer late winter weather. The migration times of many bird species have shifted in response to earlier spring weather.

Question 175

What affects will a warmer climate have on tree species?

Answer 175

Warmer climate will cause some tree species to shift their ranges to higher latitudes or elevations for cooler climate conditions.

Question 176

How will a warmer climate affect the maple tree population?

Answer 176

The sugar maple tree’s sap, which is boiled down to make maple syrup, flows when temperatures are above freezing by day and fall below freezing at night. These conditions only happen for a few weeks each year, mostly in late winter and early spring. But warmer, earlier springs and fewer freezing nights will likely push the trees’ preferred habitat northward.

Question 177

How has climate change contributed to a loss of ice? What are the statistics? How does this put Arctic and Antarctic animals in danger?

Answer 177

Ice once covered six million square miles of the Arctic Ocean in winter, decreasing to three million in summer. By 2012, ice covered just one million square miles in summer. Some scientists predict that the Arctic could have its first ice free summer by 2020. The loss of ice also affects animal species, such as polar bears, which need ice as a platform to hunt for their main food, seals.

Question 178

How have the loss of ice and rising temperatures impacted the jet stream? Why is this detrimental?

Answer 178

The loss of ice and rising temperatures have weakened the jet stream. As a result, weather systems are no longer pushed as quickly across the continent from west to east by these winds. They linger, leading to longer cold spells and stormy weather in winter, or droughts and heat waves in summer.

Question 179

Jet stream Definition

Answer 179

a band of strong winds high in the atmosphere

Question 180

How has climate change affected mountain glaciers.

Answer 180

Mountain glaciers have shrunk in the warmer climate. Glacier National Park had almost 150 glaciers in 1910. In 2015 the park had only 26. Glaciers are drinking water reservoirs, storing 70 percent of Earth’s freshwater. The water is released slowly into streams. The meltwater regulates stream temperature for aquatic life, and keeps drinking water flowing even during summer when weather is hot and dry.

Question 181

In 2017, how big was the piece that broke form the Antarctic ice sheet? What are the other affects of the warming climate on ice?

Answer 181

The Antarctic ice sheet is also melting. In July of 2017, a huge ice shelf the size of Delaware broke from the edge of Antarctica and splashed into the ocean. Before that several other ice shelves collapsed and melted into the sea. Between the collapse of Antarctic ice sheets, melting of the Arctic ice cap, and shrinking glaciers, a large amount of additional water is entering the ocean. The ocean water is also warmer. The result has been a rise in sea level. Predictions place the rise at one to four feet by the end of this century.

Question 182

How is climate change increasing the risk of flooding?

Answer 182

Coastal flooding already occurs more frequently, especially during storms. Many coastal cities such as Miami and New York City are just a few feet above sea level. Large areas of these cities could end up underwater. Low-lying islands and coasts will suffer the worst effects of sea level rise. As much as 17 percent of Bangladesh might have to be abandoned by 2050. Most of the Marshall Islands are no more than six feet above sea level. Parts of the islands are already disappearing. As the Pacific Ocean rises around them, the islands could be underwater in coming decades.

Question 183

How has a warmer climate increased the risk of wildfires?

Answer 183

Wildfires that burn thousands of acres of forest land have become more frequent, the result of climate that is hotter and drier than in the past. Drier winters and warmer springs take moisture out of plants, leaving them more susceptible to burning. As a result, “fire season” is no longer just a few months in summer. It starts earlier in spring and lasts into fall.

Question 184

How has a warmer climate increased the amount of precipitation and effected the course of winds and ocean currents?

Answer 184

Average global precipitation has also increased 0.08 inches per decade since 1901, with the U.S. averaging twice that number. The temperature of the atmosphere affects climate by changing wind and precipitation patterns as well as the movement of ocean currents. Increased heat results in more evaporation and precipitation overall, although local conditions can cause some areas to have drought.

Question 185

What is the composition of greenhouse gases in the atmosphere?

Answer 185

0-4% is water vapor, 0.04% is carbon dioxide, and there are trace amounts of methane, nitrous oxide, and fluorinated gases.

Question 186

What did scientists report about the top layer of the ocean in 2018?

Answer 186

Scientists report that the top layer of the ocean, about the top 1,981 m (6,500 ft.), was hotter in 2018 than it has ever been. That has led to absorption of more carbon dioxide and greater ocean acidity.

Question 187

Remember: The ocean’s absorption of carbon dioxide is a natural process. But as the amount of carbon dioxide in the atmosphere increases, the amount absorbed by the ocean will also increase. The ocean absorbs between 25 and 30 percent of the carbon dioxide released into the atmosphere.

Answer 187

The ocean’s absorption of carbon dioxide is a natural process. But as the amount of carbon dioxide in the atmosphere increases, the amount absorbed by the ocean will also increase. The ocean absorbs between 25 and 30 percent of the carbon dioxide released into the atmosphere.

Question 188

How is the ocean’s acidity affecting animals?

Answer 188

When the ocean is more acidic, there are fewer carbonate ions in the water. Marine organisms need carbonate ions to form shells. Because the ions are scarcer in acidic water, an increase in acidity threatens the survival of animals with shells or hard skeletons, such as corals, clams, and oysters.