Topic 17: Global Climate Change

Which of the following is not an adaptation strategy for addressing future climate change? A. Planting drought-resistant crops B. Revegetating coastal wetlands C. Erecting a seawall along coastlines D. Switching to renewable energy sources E. Restricting coastal development

D. Switching to renewable energy sources is NOT an adaptation strategy for addressing future climate change. Adaptation strategies are designed to cushion ourselves from the impacts of climate change. In other words, we will adapt to changes that are occurring. Planting drought-resistant crops and revegetating coastlines will help us grow food in a drier environment and help protect coastlines from the impact of severe storms. Erecting seawalls and limiting development along coasts will help protect towns from rising sea levels and more intense storms. Switching to renewable energy sources will prevent greenhouse gas emissions, which is a mitigation (not an adapatation) strategy.

Which of the following has been predicted, and observed, as a consequence of global climate change? A. Coastal flooding B. Wildfires C. Decrease in arctic sea ice D. Changes in the distribution of species E. All of the answers are correct.

E. All of the answers have been both predicted and observed. Low-lying coastal areas are being flooded as sea levels have risen 21 cm (8 inches) since 1900, displacing people and increasing damage and economic costs. Increasing wildfires have been seen in many parts of the world, as droughts and heat waves are intensifying, affecting farms, forests, and health. Polar ice and mountain glaciers are melting, contributing to sea level rise and reduced drinking water supplies. Most organisms and ecosystems are being affected, and some species could go extinct.

How can an El Niño/La Niña Southern Oscillation (ENSO) affect weather? A. Floods B. Drought C. Increased rainfall D. Cooler, wetter winters E. All of these can occur due to ENSO.

E. An El Niño/La Niña Southern Oscillation (ENSO) event involves changes in atmospheric pressure, sea surface temperature, and ocean circulation over the central equatorial Pacific Ocean, which leads to a reversal of the trade winds and can change weather patterns over the entire planet, leading to floods, drought, rainstorms, and cooler, wetter winters.

By burning less gasoline, a hybrid car produces less CO2, which might reduce __________. A. global climate change B. acid rain C. ozone depletion E. bioremediation F. All of the answers are correct.

A. A hybrid car produces less CO2, which might reduce global climate change. The vast majority of scientists now agree that rising concentrations of greenhouse gases, such as carbon dioxide, methane, and nitrous oxide, in the atmosphere are changing global climate patterns.

Which of the following is related to coral bleaching? A. Climate change B. Invasive species C. Habitat destruction D. Overexploitation

A. Climate change is related to coral bleaching. Coral bleaching is the loss of color in corals that can be induced by changes in temperature (climate change). The loss of corals can cause a cascade of effects in these ecosystems. Other factors such as habitat loss, overexploitation, and invasive species are affecting corals but are not the causes of bleaching

In which terrestrial area is global warming most likely to allow coniferous trees to encroach? A. Arctic tundra B. Tropical wet forests C. Temperate forests D. Boreal forests

A. Coniferous trees exist in boreal forests, with warming temperatures, they would be expected to migrate north into areas currently occupied by arctic tundra and not south into temperate or tropical forests.

Which of the following greenhouse gases (GHGs) have decreased in the past few decades? A. None; all of these have increased. B. Carbon dioxide (CO2) C. Methane (CH4) D. Nitrous oxide (N2O)

A. None; all of these have increased, not decreased, in the past few decades: CO2 in the atmosphere has increased almost 25% since 1957, CH4 has more than doubled, and N2O has also steadiy increased in the past few decades. Ozone is not a greenhouse gas.

Which one of the following environmental challenges has so far not shown a slowdown, partial recovery, or significant recovery? A. Phosphate pollution B. Climate change C. Acid rain D. Ozone hole

B. Global climate change has so far not shown a slowdown, partial recovery, or significant recovery. Regulatory measures by the United States and other countries have contributed to at least a slowdown in, if not significant recovery for, phosphate pollution, acid rain, and ozone depletion. The primary concern that has not been adequately addressed is global climate change.

What will be the effect of global warming on global species diversity? A. Overall, biodiversity will remain about the same because new species will evolve to occupy new niches created by global warming. B. Overall, biodiversity will drop. C. It is too soon to tell what the effects of global warming will be. D. Global warming will affect different parts of the globe differently, so species loss cannot be predicted.

B. Although some species might benefit from changes that occur due to global warming, overall, biodiversity will drop across the globe. This is because many species will be unable to adapt to the rapid changes that are occurring associated with global warming.

What can be said about using computer models in climate change research? A. While promising, computer models cannot yet be used by climate scientists. B. Computer models have been proven to be very wrong about future climate changes. C. The climate is far too complex to be accurately modeled. D. Computer models can be used to forecast future climate change. E. Scientists don't trust computer models, so they are hesitant to use them.

D. Climate models are indespensable for modern climate change research because the computer models can be used to forecast future climate change. They allow us to make informed predictions about future climate conditions. In the past, computer models were not very sophisticated, but a recent study showed that the most recent models have reached an unprecedented level of realism.

In 2007, how did the U.S. Supreme Court weigh in on the climate change issue? A. The Supreme Court ruled that carbon dioxide was a pollutant and that the EPA could regulate it under the Clean Air Act. B. The Supreme Court agreed with industry groups that carbon dioxide is not a pollutant and the EPA has no jurisdiction to regulate it. C. The Supreme Court ruled that coal-burning power plants must be phased out. D. The Supreme Court ruled that states have the right to limit carbon dioxide emissions. E. The Supreme Court ruled that the federal government overreached its authority and could not regulate carbon dioxide.

A. In 2007, the Supreme Court ruled that carbon dioxide was a pollutant and that the EPA could regulate it under the Clean Air Act. Since then, the EPA determined that greenhouse gases posed a danger to public health and welfare, so it would regulate carbon dioxide and other greenhouse gases. Many industry groups have been infuriated, and many in Congress want to block the EPA from fulfilling this role.

One way to slow the rate of climate change could be through fertilizing the ocean with nutrients such as iron. This will increase the growth of algae. How would this reduce the greenhouse effect? A. It would produce oxygen, which reflects sunlight from the atmosphere. B. Algae would use CO2 in photosynthesis, reducing atmospheric CO2, which would otherwise trap heat in the atmosphere. C. It would "repair" Earth's ozone layer. D. It would change the color of the ocean, thus reflecting the sun's heat. E. It would trap the sunlight that would otherwise warm Earth.

B. Geoengineers have suggested slowing the rate of greenhouse warming by fertilizing the ocean to increase the growth of algae. This would reduce the greenhouse effect because algae would use CO2 through photosynthesis, which in turn would reduce atmospheric carbon dioxide. Carbon dioxide is one of the most important greenhouse gases and is also a raw material for photosynthesis. While photosynthesis does release oxygen, oxygen does not reflect sunlight. Although O3 (ozone) in the stratosphere protects life on Earth from UV radiation, algae produce O2, not O3. Algae would not change the color of the ocean significantly enough to reflect the sun's heat. Trapping sunlight in the atmosphere would warm Earth, not protect it from the warmth.

Considering the current scientific literature on global warming, which statement best summarizes the most recent findings? A. Scientific experts have concluded that carbon dioxide is the sole cause of global warming. B. Worldwide, scientists agree that there is overwhelming evidence that the rise in temperature is due to increased greenhouse gas emissions that come from burning fossil fuels and deforestation. C. Scientific experts have concluded that current evidence suggests that most of the warming over the past 50 years is attributable to human activities. D. Scientific experts have concluded that current evidence suggests no link between human activity and climate change.

B. The Intergovernmental Panel on Climate Change concluded that the evidence for global warming is unequivocal and that it is very likely due to human-induced changes in greenhouse gases. It does not rule out that this warming can be in part due to a natural cycling of Earth but states that, due to the rate at which warming is occurring, such natural cycling is unlikely to be the sole cause.

The main cause of the increase in the amount of carbon dioxide in Earth's atmosphere over the past 150 years is __________. A. additional respiration by the rapidly growing human population B. the clearing of large areas of forests and burning of fossil fuels C. increased planting of forests D. increased worldwide planting of crops

B. The main cause of the increase in the amount of carbon dioxide in Earth's atmosphere over the past 150 years is the clearing of large areas of forests to make room for crops, pastures, villages, and cities, and also the burning of fossil fuels. Worldwide, forests are being cut faster than they are being planted, with the result that there are fewer trees to remove atmospheric carbon dioxide through photosynthesis. Although croplands are being increased, their photosynthetic rate cannot remove enough carbon dioxide to make up for deforestation and emissions from burning fossil fuels.

Which of the following are the main greenhouse gases contributing to global climate change? A. H2O (water), CO (carbon monoxide), N2O (nitrous oxide) B. aerosols, CH4 (methane), CO2 (carbon dioxide) C. CH4 (methane), CO2 (carbon dioxide), N2O (nitrous oxide) D. N2O (nitrous oxide), PCB, CH4 (methane) E. CH4 (methane), CFC (chloroflurocarbon), PCB

C. CH4, CO2, N2O are the main greenhouse gases contributing to global climate change. The scientific debate about global climate change is over. The vast majority of scientists now agree that rising concentrations of greenhouse gases, such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), in the atmosphere are changing global climate patterns. While water is a greenhouse gas, it has not increased in the atmosphere, and is not considered a major cause of climate change. Carbon monoxide is a colorless, odorless gas that can kill people, but is not considered a greenhouse gas. Aerosols, microscopic droplets and particles can have either a warming or cooling effect, depending on their composition. PCB is a pollutant that acts as an endocrine disruptor, but is not a greenhouse gas. CFCs deplete the ozone.

What can ice cores tell us about Earth's history? A. The type of pollen that existed decades ago B. Tree ring growth C. The atmospheric composition, greenhouse gases, and temperature trends from hundreds of thousands of years ago D. If fossil fuels were abundant E. Whether carbon in sediments was more abundant than it is today

C. Ice cores can tell us Earth's atmospheric composition, greenhouse gases, and temperature trends from hundreds of thousands of years ago. Over the centuries, snow falling in the poles and on high mountains has been compressed into ice, trapping tiny bubbles of the ancient atmosphere. Scientists can examine the trapped air bubbles and obtain information on the atmospheric composition, greenhouse gas concentrations, temperature trends, and solar activity over the past 800,000 years. Pollen, sediments, and tree rings can provide other evidence of past climate, but they are not found in ice cores.

So far, global climate change is having its greatest effect on __________. A. tropical forests B. the deep ocean C. arctic regions D. deserts E. temperate forests

C. So far, global climate change is having its greatest effect on arctic regions. Warming is greater over land than over sea, and the largest increases in temperature are in the northernmost arctic regions of the Northern Hemisphere. In parts of Alaska and Canada, for example, the temperature has risen 1.4°C just since 1961. Some of the consequences of the global climate change trend are already apparent in rising temperatures, unusual precipitation patterns, and melting ice.

Why is the greenhouse effect necessary for life on Earth? A. It allows photosynthesis. B. It removes greenhouse gases from the atmosphere. C. It heats the Earth's surface. D. It provides sunlight to remote regions of Earth. E. This is an incorrect statement; it is not necessary for life on Earth.

C. The greenhouse effect necessary for life on Earth because it heats the Earth's surface. Energy from the sun is either reflected by Earth's atmosphere back to space or absorbed. The absorbed radiation is then reemitted as longer wavelength infrared radiation. Greenhouse gases in the atmosphere absorb the infrared radiation and are warmed, in turn reradiating heat energy back to Earth's surface. Without this greenhouse effect, Earth would be cold and lifeless.

Which greenhouse gas is the most significant contributor to global warming? A. Methane (CH4) B. Nitrous oxide (N2O) C. Carbon dioxide (CO2) D. CFCs E. Water (H2O)

C. While all of these are, indeed, greenhouse gases, carbon dioxide (CO2) is considered the most important because of the enormous amounts that are emitted each year by humans and thus is considered the most significant contributor to global warming. Some gases, such as methane, can absorb more heat per molecule, but they are not emitted in the huge amounts that carbon dioxide is.

A. Nothing, there is no difference between the two terms. B. Global warming is an old term that has been replaced by climate change. C. Global warming scared too many people, so scientists changed it to climate change. D. Global warming refers to an increase in Earth's average temperature, while climate change encompases a wide variety of changes in Earth's climate. E. Global warming is not happening, while climate change is.

D. Global warming refers specifically to an increase in Earth's average surface temperature, while climate change encompasses a wide array of changes in Earth's climate, including global warming.

Climate change, as demonstrated by observations such as the rise in average ambient temperatures and the melting of glaciers, has already had many effects on living organisms. Which of the following might best offer a solution to this problem? A. Continue to measure these and other parameters of the problem. B. Increase the abilities of animals to migrate to more suitable habitats. C. Do nothing; nature will attain its own balance. D. Limit the burning of fossil fuels and limit the loss of forested areas. E. Recycle as much as possible.

D. There is overwhelming scientific evidence that burning fossil fuels and deforestation have increased the amount of greenhouse gases in the atmosphere, which has led to climate change and a warmer planet. Thus, the solution to global warming is to limit the burning of fossil fuels, limit the loss of forests, and replant deforested areas. Although there is a need to continue monitoring, measuring, and studying Earth's climate and the impact of burning fossil fuels and deforestation, there is no longer significant doubt that these activities are causing our climate to change. Animals may or may not be able to migrate to other areas, due to habitat loss, changing habitats in the face of a changing climate, and increased human populations that are limiting the available habitat animals might be able to move to. If we do nothing, and keep burning fossil fuels and cutting forests, scientists predict that the impacts we are already seeing will only get worse. While recycling will help conserve materials, and save on energy costs, we must address the root causes of climate change: burning fossil fuels and deforestation.

What was the main goal of the 1997 Kyoto Protocol? A. To allow developed countries several more years before they had to set targets to reduce emissions B. To force developing countries to set targets to reduce carbon dioxide emissions C. To inhibit economic development by setting targets D. To force countries to set limits on ozone-depleting chemicals E. To reduce emissions of six greenhouse gases based on each country's history and phase of development

E. In 1997, most of the world's nations met in Kyoto, Japan, to formulate a more aggressive treaty to reduce emissions of six greenhouse gases based on each country's history and phase of development. Targets for developed countries were based on historical levels of emissions, while developing countries (such as China and India) had no targets (based on fears that targets would interfere with development). The Montreal Protocol addressed ozone-depleting chemicals.

Which of the following is not a prediction of human-caused climate change? A. More intense storms B. Longer, more frequent heat waves C. Longer growing seasons D. Drier regions having less precipitation E. Lower sea levels due to increased drainage

E. Lower sea levels due to increased drainage is not a prediction of human-caused climate change. The sea level is currently rising at almost 3.2 mm per year and will continue to rise due to thermal expansion and melting snow and ice. As a consequence of climate change, storm intensities will increase, growing seasons will lengthen, and drier regions will get drier.

Which of the following is not a mitigation strategy for addressing future climate change? A. Improving energy efficiency B. Preventing deforestation C. Cap-and-trade policies D. Reduced use of fossil fuels E. Modifying water management practices to cope with drought

E. Modifying water management practices to cope with drought is NOT a mitigation strategy for addressing future climate change. Mitigation strategies focus on reducing greenhouse gas emissions so that the effects of climate change are less severe. To help determine whether something is a mitigation strategy, ask yourself if the activity will prevent greenhouse gases from being released. Improving energy efficiency and reducing use of fossil fuels reduce carbon dioxide emissions. Preventing deforestation leaves vegetation in place, which allows photosynthesis that removes carbon dioxide from the air. Cap-and-trade policies put an economic price on emissions, so industries theoretically will look for ways to reduce their emissions. Modifying water practices to cope with drought does not prevent emissions; it is a response to climate change that has happened or is happening.

Which of these countries do you suppose produces the most carbon dioxide per person? A. Mexico B. Indonesia C. India D. Tanzania E. United States

E. Of the countries listed, the United States produces the most carbon dioxide per person. Fossil fuels consist of biomass that was buried under sediments before completely decomposing. The burning of fossil fuels and wood can be thought of as a rapid form of decomposition. In this process, carbon atoms that make up the organic fuel are released as CO2. The CO2 flooding into the atmosphere from the combustion of fossil fuels comes from heavily industrialized nations such as the United States.