Deck 19: The Changing Earth System

Question 1

Scientists have developed a number of geo-engineering approaches to limit incoming solar radiation, which would then cool the planet. One of the ideas is to launch enormous orbiting mirrors or reflective shields to limit the amount of incoming solar radiation. Is this a reasonable idea? Other than costs associated with building and launching such a device, can you think of any other inherent risks or issues with such an undertaking?

Answer 1

While the idea of launching enormous orbiting mirrors or reflective shields to limit incoming solar radiation may seem like a potential solution to cool the planet, there are several inherent risks and issues associated with such an undertaking.

Firstly, the environmental and ecological impacts of manipulating incoming solar radiation on a large scale are not fully understood. It is possible that altering the amount of solar radiation reaching the Earth could have unintended consequences on weather patterns, ecosystems, and agriculture.

Additionally, the deployment and maintenance of such a large-scale geo-engineering project would require significant resources and international cooperation. The costs associated with building and launching the necessary devices would be substantial, and there would likely be political and logistical challenges in coordinating such a global effort.

Furthermore, there are potential ethical concerns surrounding the idea of deliberately manipulating the Earth's climate. The long-term effects of such geo-engineering approaches are uncertain, and there is a risk of creating further environmental imbalances or exacerbating existing climate issues.

In conclusion, while geo-engineering approaches such as launching orbiting mirrors or reflective shields may offer a potential solution to limit incoming solar radiation and cool the planet, the inherent risks and issues associated with such an undertaking must be carefully considered before pursuing such a solution. It is essential to thoroughly evaluate the potential environmental, economic, and ethical implications before implementing large-scale geo-engineering projects.

Question 2

How is the concept of the ecological footprint related to that of carrying capacity?

Answer 2

The concept of the ecological footprint is related to the concept of carrying capacity in that both concepts are measures of the impact of human activity on the environment. The ecological footprint measures the amount of biologically productive land and water area required to produce the resources a population consumes and to absorb its waste, while the concept of carrying capacity refers to the maximum population size that an environment can sustain indefinitely.

The ecological footprint helps to illustrate the demands that human populations place on the Earth's resources, while carrying capacity helps to determine the Earth's ability to support those demands. By comparing the ecological footprint of a population to the carrying capacity of the environment, we can assess whether the population is living within the means of the environment or exceeding its capacity to support them.

In this way, the ecological footprint and carrying capacity are closely related as they both provide valuable information about the sustainability of human activity and its impact on the environment. By understanding and considering these concepts, we can work towards living within the Earth's means and ensuring the long-term health of our planet.

Question 3

By 1914, at the beginning of World War I, the abundance of Bowhead whales decreased from 50,000 to about __________ .

Answer 3

3,000

Question 4

One way to quantify the human impact on Earth systems and to explore interactions among population, lifestyle, technology, and the environment is the ___________ equation.

Question 5

One way for decision makers to deal with risk is to rely on the ____________ principle, the concept that if the potential consequences of an event are unacceptably severe, those in authority have a responsibility to take action.

Question 6

____________is the expansion of desert conditions into previously productive land areas.

Question 7

Mining, road construction, and other earth-moving activities contribute dramatically to exposure and ultimately erosion of ___________ .

Question 8

As the __________ has grown and become more industrialized, people have altered the natural flow of rivers and released ever-larger amounts of waste.

Question 9

Surface water reservoirs in industrial areas are susceptible to ___________ pollution -- the release of heat or heated water (which is harmful to aquatic organisms and ecosystems).

Question 10

An algal __________ can occur when an aquatic system is overloaded with nutrients.

Question 11

As __________rise into the upper atmosphere, ultraviolet radiation breaks them down, releasing chlorine in the form of chlorine monoxide.

Question 12

At present, forests are experiencing the greatest impacts from clear-cut logging and other forms of land clearing.

Question 13

The United Nations Food and Agriculture Organization reports that __________ percent of the world's fish stocks are now fully exploited, overexploited, or depleted.

Question 14

The __________ effect results from the absorption of outgoing heat from Earth's surface by radiatively active gases in the atmosphere, such as carbon dioxide, methane, and water vapor.

Question 15

A __________ atmosphere will lead to increased evaporation from oceans, lakes, and streams.

Question 16

___________ gas absorbs infrared radiation 25 times more efficiently that carbon dioxide.

Question 17

___________ have been successful in simulating the general character of present-day climates and have greatly improved weather forecasting.

Question 18

The burning of fossil fuels and the clearing of forested land cause __________ to move from the geosphere and the biosphere to the atmosphere.

Question 19

Scientists estimate that in the past 200 years the rate of species __________ has soared to thousands per decade.

Question 20

__________ reefs are formed by colonies of tiny animals which coexist in a symbiotic relationship with photosynthetic algae.

Question 21

Human actions generally have insignificant, short-lasting impacts on the Earth system.

Question 22

It would take about 10 Earths to meet current resource needs sustainably.

Question 23

Malthus argued that human population grows exponentially while resource availability grows linearly.

Question 24

Because of human's strong understanding of the natural world, the problems associated with global change are relatively simple problems to solve.

Question 25

Human activity affects the hydrosphere but not the geosphere.

Question 26

The open ocean is relatively free of pollution, but marine coastal zones are vulnerable to the impacts of human activity.

Question 27

Local air pollution can become regional or global as a result of longer-range transport.

Question 28

Human activity affects the atmosphere but not the biosphere.

Question 29

Human activity has not changed the composition of the atmosphere since the Industrial Revolution.

Question 30

Changes in the concentration of atmospheric greenhouse gases have the potential to affect the stability of Earth's climate system.

Question 31

Measured average annual temperature curves all show a rise in temperature over the past century of approximately 5 to 10 degrees Centigrade.

Question 32

Global Circulation Models have been successful in simulating present-day climates, which increases the confidence of scientists in their ability to predict future climatic change.

Question 33

The addition of warmer, fresher water to the oceans could inhibit the formation of the cold, deep, saline waters that drive the global thermohaline circulation.

Question 34

Global climate change will have impacts on the hydrosphere, but not on the biosphere.

Question 35

Rising summer air temperatures in the Arctic will thaw permanently frozen ground.

Question 36

Global climate change will have impacts on the geosphere.

Question 37

Some of the responses of natural Earth systems to global climatic warming may further enhance the warming trend, leading to positive feedbacks.

Question 38

There really are no options for dealing with global climate change. The only thing we can do is wait and prepare to adapt to the changes that occur.

Question 39

Over the past few decades, air and water quality have improved.

Question 40

What does ozone protect us from?

A) Infrared Rays.
B) UV Rays.
C) Meteorites.
D) All of these.

Question 41

Which of the following is not a variable in the IPAT equation?

A) Sensitivity.
B) Population.
C) Affluence.
D) Technology.
E) Demographic.

Question 42

Throughout history, there have been times when human population growth __________ as a result of the development of new technologies, and times when population growth __________ as a result of environmental resistance.

A) Surged, slowed.
B) Slowed, surged.
C) Stayed the same, surged.
D) Slowed, stayed the same.

Question 43

Where is desertification occurring today?

A) Denmark.
B) The island of Hawaii.
C) Most of the world's tropical rainforests.
D) Sahel region of Africa.

Question 44

About how many hectares of arid land do some researchers believe have increased since 1931 as a result of a 30% decline in rainfall during this interval in arid regions (versus human contribution to land degradation)?

A) 5 million
B) 100 million
C) 10 million
D) 50 million

Question 45

Which of the following is a reason to build a dam?

A) Flood control.
B) Hydroelectric power.
C) Divert water to other locations.
D) These are all potential reasons to build a dam.

Question 46

Which of the following happened to parts of Lake Erie in the 1970s?

A) Argon-depletion.
B) Carbon-depletion.
C) Nitrogen-depletion.
D) Oxygen-depletion.

Question 47

What happened in Chernobyl, Ukraine in 1986?

A) Nuclear meltdown.
B) Population explosion.
C) Outbreak of a plague.
D) Massive flooding.

Question 48

As a result of measures to cut back on emissions of ozone-depleting substances, stratospheric ozone levels are expected to return to 1980 levels by around __________ in midlatitude regions and __________ in Antarctica.

A) 2080, 2045.
B) 2045, 2080
C) 2100, 2700
D) 2020, 2030

Question 49

What is the pH of natural rain?

A) About 2.6.
B) About 5.6.
C) About 7.7
D) About 5.0

Question 50

How is carbonic acid (HCO3) formed in the atmosphere?

A) Interaction of water and carbon dioxide.
B) Interaction of water and sulfur oxides.
C) Interaction of water and nitrous oxides.
D) Interaction of water and carbon.

Question 51

The only gas in the atmosphere that can absorb UV rays is

A) Methane.
B) Carbon dioxide.
C) Water vapor.
D) Ozone.

Question 52

Depletion of the Earth's ozone layer is expected to lead to which of the following consequences?

A) Increases in sea surface temperatures.
B) Increases in skin cancer.
C) Threats to plankton.
D) These are all consequences of ozone depletion.

Question 53

Acid rain is primarily a problem of

A) Developing nations.
B) Developed nations.
C) Urban areas.
D) Wilderness.

Question 54

The major greenhouse gases in the atmosphere are

A) Carbon dioxide, water vapor, methane.
B) Carbon dioxide, oxygen, water vapor.
C) Carbon dioxide, methane, nitrogen.
D) Carbon dioxide, oxygen, nitrogen.

Question 55

Which of the following statements concerning global warming is false?

A) Carbon dioxide in the atmosphere now totals about 150% of its pre-Industrial Revolution levels.
B) From 1860 to 2010, the mean global temperature rose about 0.5 to 0.8 degrees Centigrade.
C) The seven warmest years in recorded history occurred between 1903 to 1910.
D) These are all false.

Question 56

Which international agreement led to the phase out of the use of CFCs?

A) Kyoto Protocol of 1997.
B) Montreal Protocol of 1987.
C) Intergovernmental Panel on Climate Change of 1988.

Question 57

What do most current climate models suggest will happen to global temperatures by the end of the 21st Century?

A) Temperatures will be at least 2 to 4 degrees Centigrade higher than today.
B) Temperatures will be at least 6 to 8 degrees Centigrade higher than today.
C) Temperatures will be at least 10 to 12 degrees Centigrade higher than today.
D) Temperatures will be at least 14 to 16 degrees Centigrade higher than today.

Question 58

Which of the following greenhouse gases is the most efficient in absorbing infrared radiation?

A) Methane.
B) Carbon dioxide.
C) Water vapor.

Question 59

Tropical areas are biodiversity "hotspots". They represent just __________ percent of the world's land surface, but collectively hold at least 44 percent of all vascular plant species and 38 percent of all vertebrate animal species.

A) 10.
B) 5.
C) 8.
D) 2

Question 60

The results of the Montreal protocol of 1987 include which of the following?

A) Recycling of CFCs.
B) Reduced production of CFCs.
C) Production of alternatives to CFCs.
D) All of these.

Question 61

If you were to build a dam in order to reroute a river, which of the following would be affected?

A) The natural vegetation that exists downstream.
B) The population of fish that lives downstream.
C) Migratory animals that drink from the water.
D) The population of people that live downstream.
E) All of these.

Question 62

Scenario: A large area in a semi arid climate has been affected by a decrease in rainfall over the last decade. This area is in danger of

A) Deforestation.
B) Desertification.
C) Surface water contamination.
D) Groundwater contamination.

Question 63

Water pollution can generally result from all of the following, except

A) Rerouting a river.
B) Urbanization.
C) Excessive fertilization.
D) Mining.

Question 64

Accelerated soil erosion is often closely related to

A) Mining.
B) Dam building.
C) Deforestation.
D) All of these.

Question 65

In different parts of the world, which of the following is a major source of water for human consumption?

A) Desalinated water.
B) Groundwater.
C) Rainwater.
D) All are sources for human consumption.

Question 66

Where do contaminants in surface water mainly originate?

A) Suburban runoff only
B) Urban runoff only.
C) Urban, suburban, and agricultural runoff.
D) Agricultural runoff only.

Question 67

The Mississippi River flows into the Gulf of Mexico. Near the deposition point, there is a "dead zone". At this zone, few animals can live. The water here is depleted in oxygen. Why is this?

A) Mainly due to cultural eutrophication.
B) The water is swamp-like and doesn't circulate oxygen well.
C) Hydrocarbons from the Gulf break-down the oxygen molecule.
D) None of these.

Question 68

Some of the impacts of air pollution are ___________, but many are __________ ; they result from the long-range transport of airborne pollutants.

A) Regional, local.
B) Local, regional.
C) Global, local.
D) Not felt, felt.

Question 69

In what layer of atmosphere is the ozone that projects us from UV rays located?

A) Thermosphere.
B) Mesosphere.
C) Stratosphere.
D) Troposphere.

Question 70

Other than carbon dioxide, methane, and water vapor, both __________ and __________ are greenhouse gases.

A) Oxygen, nitrogen.
B) Oxygen, ozone.
C) Ozone, nitrous oxide.
D) Sulfate, carbonate.

Question 71

Of the following choices, which is the largest reservoir for carbon?

A) Tropical rainforests.
B) Urban centers.
C) Deserts.
D) Temperate zones.

Question 72

New species arise as a result of

A) Speciation.
B) Evolution.
C) Natural Selection.
D) All of these.

Question 73

According to scientists from the International Geosphere-Biosphere Program, three boundaries of the planetary system have already been crossed. What are they?

A) Climate change, the nitrogen cycle, and biodiversity loss.
B) Biodiversity loss, ozone depletion, land-use change.
C) The nitrogen cycle, ocean acidification, biodiversity loss.
D) Climate change, global freshwater use, ozone depletion.