Although most scientists agree that humans have in some way influenced climate change, whether humans should try to stop global warming is one of the most hotly debated topics in the scientific world. In fact, of all the points about which scientists disagree on the global warming issue, a possible solution seems to spark the fiercest debate. Some say that the planet is more robust than fragile—that it has always managed to maintain the right balance in the past, and it will naturally correct itself in the future. Others, however, insist that since people have caused warming, people must take corrective measures to stop it.
The scientists who are most alarmed about global warming insist that in order to fix it, the burning of fossil fuels must be dramatically cut back. This would not make an immediate difference because heat-trapping gases such as carbon dioxide and methane will remain in the atmosphere for many years. But if steps were taken now to reduce emissions, the gases would eventually begin to diminish and the rate of global warming would slow.
However, that would be anything but simple because fossil fuels are used by people all over the world. Petroleum products furnish power for all different kinds of transportation. Oil and natural gas are used to heat homes, stores, and office buildings, as well as everything from small businesses to multimillion-dollar corporations. Coal is burned to operate water treatment plants, and to run power plants that generate much of the world's electricity. If fossil fuel use were suddenly cut, it would require people to make major changes in their lives.
Some scientists warn that reducing the use of fossil fuels would cause great financial hardship. This is especially true in the United States because America's economy is more dependent on fossil fuels than that of other countries. Since economic growth depends on energy, scientists such as Fred Singer believe that any move to restrict the use of coal—the cheapest fuel available—could cause electricity prices to skyrocket. Singer explains his perspective about cutting back on fossil fuels:
I'm not a great believer in buying insurance if the risks are small and the premiums are high. Nobody in his right mind would do that. But +this is the case here. We're being asked to buy an insurance policy against a risk that is very small, if at all, and pay a very heavy premium. We're being asked to reduce energy use, not just by a few percent but . . . by about 35 percent within ten years. That means giving up one-third of all energy use, using one-third less electricity, throwing out one-third of all cars, perhaps . . . it would hit people very hard, particularly people who can least afford it. 43
Like Singer, Thomas Gale Moore believes that the cost of doing away with fossil fuels would be too high of a price for people to pay. He explains: "Let's not rush into costly programs to stave off something that we may like if it occurs. Warmer is better, richer is healthier; acting now is foolish." 44
Other scientists, however, believe that the cost of reducing fossil fuels will be much lower than people think. Studies done by the U.S. Department of Energy show that the United States could reduce its CO 2 emissions at a low cost, and perhaps even save money in the long term. John J. Berger believes that the claims sometimes made about high costs are untrue or exaggerated. He says that an effort to reduce dependence on fossil fuels could actually stimulate the economy and vastly improve the planet. He shares his thoughts on how the planet—and also the world economy—would benefit by cutting back on fossil fuel use: "Lakes and streams would sparkle. . . . The threat of global climate change due to human activities would vanish. The U.S. would go from being the world's major cause of global warming to being the world's premier source of clean energy systems [renewable energy]." 45 Berger points out that if the world reduced its dependence on fossil fuels, the environment would be cleaner, the quality of life would be improved, and people would save money on energy costs.
Scientists who are in favor of cutting back on the use of fossil fuels are the first to say that it will not be easy and it will take time. Stephen H. Schneider says that the world cannot turn off its dependence on carbon-based energy overnight, but that steps must be taken now to move away from fossil fuels. He believes one possible solution is to charge higher prices for carbon-based fuels, as he explains: "If we had a price on carbon, if we weren't all allowed to use the atmosphere as a free sewer, then the inventive genius of our industrial folks . . . to invent non-carbon-based alternatives would be stimulated. As long as the price of energy remains so that a bottle of mineral water at the store costs three times more per gallon than gasoline at the pump, we haven't got incentives for that kind of development." 46
The Union of Concerned Scientists also believes that corrective measures, such as enacting CO 2 emission laws, must be taken now or the planet will suffer permanent damage. The group says that by waiting ten or twenty years, or longer, before taking action, global warming will be much more difficult to address and the problems will be more serious, as they describe:
We're treating our atmosphere like we once did our rivers. We used to dump waste thoughtlessly into our waterways. . . . But when entire fisheries were poisoned and rivers began to catch fire, we realized what a horrible mistake that was. Our atmosphere has limits too. CO 2 remains in the atmosphere for about 100 years. The longer we keep polluting, the longer it will take to recover and the more irreversible damage will be done. 47
The word polluting is at the center of many scientific debates on global warming. Those who believe that the planet would benefit from higher levels of
In the past, we've had these great struggles over pollution in the United States. Sulphur dioxide is a pollutant. . . . Carbon dioxide is a benign gas required for life on earth. It is not a pollutant. It is not regulated. There are no state laws dealing with CO 2 . There are no Congressional laws that give any agency the right to regulate based on CO 2 . So when the environmental community gets their hands on our policy apparatus in the U.S. and says, "we have to put less greenhouse gases in the atmosphere," they come first to us [the coal producers], because we are not only the biggest source of carbon dioxide, we're the biggest source of electricity. 48
Even in the absence of government regulation of CO 2 emissions, a growing number of companies have taken action on their own by setting tough environmental standards for themselves. One example is the Business Environmental Leadership Council (BELC), which was formed to address the problems of global climate change. The group is composed of large oil, gas, chemical, and utility companies that are all committed to adopting environmentally sound technologies, as well as developing better ways to produce energy. Some BELC members include IBM, Intel, Boeing, Alcoa, American Electric Power, DuPont, Whirlpool, Shell International, Sunoco, Lockheed Martin, Toyota, Hewlett-Packard, DTE Energy, Georgia-Pacific, and BP Amoco, among others. Each company sets its own goals for reducing greenhouse gas emissions, and each monitors its own progress.
For instance, DuPont's goal for the year 2010 is to reduce emissions by 65 percent from 1990 levels. Holcium, a large cement manufacturer, vowed to reduce its emissions by 12 percent per ton of product manufactured between 2000 and 2008. BP Amoco has achieved its goal of reducing emissions by 10 percent from 1990 levels, and its target for the future is not to exceed these levels through the year 2012. Shell International's goal for 2002 was to reduce emissions by 10 percent, and the company beat that goal. Shell's commitment to help stop global warming is stated on its website as follows: "The Royal Dutch/Shell Group of Companies shares the widespread concern that the emission of greenhouse gases from human activities is leading to changes in the global climate. We believe action is required now to lay the foundation for eventually stabilizing greenhouse gas concentrations in the atmosphere in an equitable and an economically responsible way." 49
Some members of the BELC are also committed to developing technologies that focus on renewable resources—resources that cannot be used up. In December 2002, BP Amoco announced the start-up of a wind farm in the Netherlands that will generate enough electricity for about twenty thousand Dutch households, without adding a trace of carbon dioxide or other greenhouse gases to the atmosphere.
As an energy source wind power is cheap to produce, pollution free, and readily available. Throughout history, wind power has been used for everything from powering ships to grinding grain, although its popularity waned as new kinds of technology developed. Now, however, according to Berger, wind power is growing faster than any other energy technology in the world. Much of that growth has been in Europe, but in March 2002, the U.S. Department of Energy announced a program called Wind Powering America. The organization's goal is to significantly increase the nation's use of wind energy by the year 2010.
Another renewable resource is hydropower—power generated through the use of flowing water. The most common type of hydropower plant uses a dam on a river or stream to capture water and store it in a reservoir. As water is released from the reservoir it flows through a turbine, causing the turbine to spin, which activates a generator that produces electricity. Not all hydropower plants require dams, though. Instead some, such as most hydropower plants in Hawaii, use small canals to channel river water through a turbine.
Like wind power, hydropower is a clean, nonpolluting energy resource. Currently, about 20 percent of the world's electricity is generated through the use of water; and in the United States, hydropower generates about 10 percent of the nation's electricity. There are some environmental concerns associated with hydropower because building new dams to restrict the flow of rivers or streams can alter natural habitats and disturb aquatic plants and wildlife. However, Berger says that existing capacity for hydropower can be expanded without having to construct new dams, as he explains: "Upgrading dams, by adding new turbines or rewinding old ones, could thus increase hydroelectric power generation by twenty-five percent, at relatively little cost, and it also might present opportunities for improving fish passage, downstream aquatic habitats, and water quality." 50
Just as there is energy potential in the earth's water, there is also great potential in sunlight because the sun emits such an enormous amount of energy. Scientists say that there is enough energy in twenty days of sunshine to equal the total energy stored in the earth's reserves of coal, oil, and natural gas.
Solar technologies harness the sun's energy and use it to provide utilities for businesses, industries, and homes. One product, called a concentrating solar system, for example, uses reflective materials such as mirrors to collect and focus the sun's heat, which then runs generators to produce electricity. Passive solar heating, cooling, and daylighting systems capture solar energy that heats and cools buildings, as well as providing a natural source of light. Solar hot water systems use the sun's energy to heat water. Photovoltaic solar cells, which convert sunlight directly into electricity, are most often used in calculators, watches, and to power outdoor light fixtures. More complex photovoltaic systems have the ability to light houses and other buildings.
Not only is there a tremendous amount of energy available from the sky above, there is also a vast store of energy buried deep in the ground. The production of geothermal energy takes advantage of that by tapping into the ancient heat of the earth's core. This heat is found at several different levels: in shallow reservoirs of hot water and steam; as hot, dry rock found deeper in the earth; and at the planet's deepest levels as molten rock.
Like sunlight, geothermal energy can be used to produce electricity. Unlike traditional power plants, geothermal power plants obtain steam to rotate turbines from a direct source found several miles below the surface of the planet. There are two kinds of geothermal power plants: dry steam plants, which pipe steam from underground wells; and flash steam plants, which convert geothermal reservoirs of hot water into steam, and then inject the unused water back into the reservoir.
There are other uses for geothermal energy besides creating steam. For example, in the western continental United States, as well as in Alaska and Hawaii, geothermal energy is used to provide heat directly to homes and businesses. Wells are drilled into geothermal reservoirs until there is a steady stream of hot water, which is drawn up through the well. Then, a mechanical system delivers the hot water for such uses as heating buildings, raising plants in greenhouses, or drying crops.
Another kind of renewable energy that has tremendous potential is biomass energy, produced from organic matter. Biomass energy makes use of waste materials generated by manufacturing, agriculture, and forestry, as well as common household garbage and sewage. One use for biomass is the generation of electricity. Waste materials are burned to produce steam that is captured by a turbine, and then a generator converts the steam into electricity. In some industries, the steam is also used for manufacturing processes or to heat buildings. For example, wood waste is often used to produce both electricity and steam at paper mills.
Another way that biomass can be used as an energy source is by recycling the methane that is emitted at landfills when organic waste materials decompose. Wells can be drilled in the landfills to release the methane from the layers of decaying matter, and then pipes from the wells carry the gas to a central point where it is filtered and cleaned before burning. One facility in Texas uses this process to generate enough electricity to power more than sixty-five hundred homes.
Because biomass can be converted to ethanol and methanol—liquid fuels that add no carbon dioxide to the air—its use could greatly reduce greenhouse gas emissions. Unlike other renewable energy sources, biomass can be converted directly into liquid fuels, called biofuels, which can be used to run cars, trucks, buses, airplanes, and trains. Many scientists believe that fuels made from biomass could go a long way toward meeting the transportation needs of the world.
Another energy source that can produce fuel for the world's transportation needs is hydrogen, the most plentiful element in the universe. Hydrogen can produce electricity, heat, or synthetic chemicals. One of hydrogen's most valuable benefits is that when it is burned in an engine, it is virtually pollution-free.
Most hydrogen is currently made from natural gas, by using steam to separate the hydrocarbons from the gas. Another way of producing hydrogen uses an electrical current to separate water into its components of oxygen and hydrogen, in a process called electrolysis. Since the 1970s, NASA has used liquid hydrogen to propel the space shuttle and other rockets into orbit. Hydrogen fuel cells power the shuttle's electrical systems, producing a clean byproduct—pure water—that the crew is able to drink. Fuel cells, which are often compared to batteries, combine hydrogen and oxygen to produce electricity, heat, and water. Scientists consider them one of the most promising technologies for the world's future energy needs.
There are no simple answers to the global warming debate. As far back as the nineteenth century, when Svante Arrhenius first proposed his theory about carbon dioxide in the atmosphere, global warming has
Patrick J. Michaels says there have been times in the past when environmental predictions were proven wrong, and he believes that global warming is the same type of issue, as he explains: "We've been throwing increasing amounts of money at this problem for years now and the fact of the matter is that we still can't tell, literally, which way is up when it comes to climate change." 51 In a separate article, Michaels, along with two other authors, writes there is no mechanism that can stop global warming in the near future because what the future holds is unknown. He also says the more serious question provoked by what is known about global warming is this one: "Is the way the planet warms something that we should even try to stop?" 52
Schneider believes that it definitely is the responsibility of humans to stop global warming, and he says measures must be taken now because time is running out for the planet: "The only way to prove it for sure is hang around 10, 20, or 30 more years, when the evidence would be overwhelming. But in the meantime, we're conducting a global experiment. And we're all in the test tube." 53