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How Global Warming Works Gases in the Earth’’s atmosphere act like glass in a greenhouse-trapping heat and making life on Earth possible. But there is a delicate balance. Burning coal, oil and natural gas increases atmospheric concentrations of these gases. Over the past century, increases in industry, transportation, and electricity production have increased gas concentrations in the atmosphere faster than natural processes can remove them leading to human-caused warming of the globe. The Sources Of Global Warming The major source of global warming is carbon dioxide pollution from power plants, auto mobiles, and industry. Another source is global deforestation. ●Power plants are responsible for more than a third of U. S. CO2 emissions, yet there are no caps on CO2 emissions from power plants or any other industry. ●Gas guzzling cars and light trucks are also responsible for a third of U.S. CO2 emissions. Current regulations allow for very inefficient vehicles which spew tons of CO2. ●Trees remove carbon dioxide from the air as they grow. When they are cut and burned that CO2is released back into the atmosphere. Massive deforestation around the globe is releasing large amounts of CO2 and decreasing the forests’’ ability to take CO2from the atmosphere. Solutions The U. S. , with only four percent of the world’’s population, is responsible for 22 percent of the world’’s greenhouse gas emissions. Fortunately, solutions exist to cut our global warming emissions. Decision makers in the United States should take the following steps. ●Increasing fuel efficiency standards for cars and light trucks would cut millions of tons of CO2 pollution as well as decreasing dependence on foreign oil. ●Putting a cap on CO2 from power plants would cut millions of tons of CO2 pollution as well as decreasing pollution that causes acid rain, smog, and respiratory illness. ●Shifting investment from fossil fuels like coal and oil to renewable energy and energy efficiency would allow cleaner, more sustainable sources of energy to take their rightful place as market leaders. ●Ratification of the Kyoto Protocol would be a modest but important first step to ward international emissions reductions. The Evidence Recently, alarming events that are consistent with scientific predictions about the effects of climate change have become more and more commonplace. The global average temperature has increased by about 0.5°C and sea level has risen by about 10 inches (25cm) in the past century. Official confirmation came in 1995, when the Intergovernmental Panel on Climate Change, an officially appointed international panel of over 2,500 of the world’’s leading scientific experts, found that evidence suggests a human influence on the global climate. The following are events which consistent with scientists predictions of the effects of global warming: ●The past two decades have witnessed a stream of new heat and precipitation re cords. The 10 hottest years on record have all occurred since 1980, the hottest year ever on record is 1997, and the hottest January through July on record occurred in 1998. ●Glaciers are melting around the world. Alaska’’s Columbia Glacier has retreated more than eight miles in the last 16 years while temperatures there have increased. A section of an Antarctic ice shelf as big as the District of Columbia broke off. ●Severe floods like the devastating Midwestern floods of 1993 and 1997 are becoming more common. ●Infectious diseases are moving into new areas as seen in the recent outbreaks of Dengue fever in Texas and Malaria in New Jersey. The Opposition The Global Climate Coalition, a powerful coalition of oil, power, and auto companies has followed the lead of tobacco companies by denying the harm they cause. They have spent millions of dollars trying to discredit the scientific consensus of the IPCC and slow steps to combat global warming. The public has not fallen for their deception, but the Global Climate Coalition appears to have had some impact on members of Congress. Health Risks Rates of infectious disease will rise, with the spread of mosquitoes and other disease carrying organisms that thrive in warm, wet climates. More frequent and more severe heat waves will pose a threat to public health, with children and the elderly especially vulnerable. In the 1990s, outbreaks of malaria have occurred in Michigan, Texas, Florida, Georgia, California, New Jersey and New York. Two major heat waves-in Chicago in 1995 and Dallas in 1998-killed more than 600 people. Environmental Destruction Rising global temperatures and melting of glaciers will directly impact ocean and coast al habitats. Ecosystems will, be destroyed and species will die off, as sea levels rise, sea sons shift, and glaciers and polar ice caps melt. Polar bears are threatened with starvation as melting sea ice keeps them from their food. Catastrophic Weather Warmer temperatures will speed evaporation, leading to drought in some places and heavy downpours and flooding in others. Extreme weather events as well as El Ninno events may become more intense and more frequent. In 1999, the U. S. experienced one of the most extreme droughts ever recorded, and Maryland, New Jersey, Rhode Island and Delaware faced their driest growing seasons on record. That same year, the Pacific North west experienced its second wettest year on record. Nevada, California and Iowa all experienced deadly floods. Recent years have seen record hurricanes, including the most destructive ever. Clean Energy Agenda A rapid transition to energy efficiency and renewable energy sources will combat global warming, protect human health, create new jobs, protect habitat and wildlife, and ensure a secure, affordable energy future. In contrast, our reliance on coal, oil and nuclear power imperils the world’’s climate, fouls the environment, harms human health, and results in the proliferation of nuclear materials. We can meet our energy needs without threatening our children’’s future using commonsense ways to mobilize American ingenuity and re sources for a rapid transition to renewable energy sources. It will eliminate energy waste, phase out fossil fuels and nuclear power, and help the United States lead the world into a sustainable energy future, Clean Power In the next decade, increase fourfold the amount of energy obtained from non-hydro renewable sources such as the sun and wind. By 2020, produce at least one-third of the nation’’s energy from renewable sources, and double the efficiency of energy use in homes, buildings, transportation and industry. Clean Air Clean up our power plants by setting progressively tighter limits on all power plant pollution-including carbon dioxide, the major cause of global warming. Close the loophole that allows old coal-fired power plants to pollute much more than newer plants. Clean Cars Hold sport utility vehicles, pickup trucks and minivans to the same air pollution standards as cars. Improve the fuel efficiency of new cars and light trucks to a combined average of 45 miles per gallon (MPG) by 2010 and at least 65 MPG by 2020. Offer incentives that build strong markets for renewable fuels and for clean vehicles powered by hybrid motors and fuel cells. Clean Investments Quadruple federal investments in renewable energy and energy efficiency within five years, and continue this momentum over the long term Stop spending taxpayer dollars to subsidize the coal, oil and nuclear industries. Provide adequate resources and job training for affected workers and communities to ensure a just transition to a sustainable energy economy. The passage gives an overview of the effects of global warming on the United States.