Extensive scientific evidence demonstrates that global warming is real, that it is affecting us now, and that human activitiesparticularly the burning of fossil fuelsare the primary cause.
Science is also clear about what we need to do to address the problem: immediately and significantly reduce emissions of the pollutants that cause global warming. Avoiding the worst consequences of global warming will require the United States and other industrialized countries to stabilize emissions within the next decade and reduce them by about 80 percent by midcentury.
Achieving those reductions wont be easy, but it can be done. By improving the efficiency with which we use fossil fuels and increasing our use of clean, renewable energy, the United States can reduce its global warming emissions in the near future, while putting America on a path toward dramatically lower global warming emissions in the decades to come.
This report lists six challenging but feasible strategies that, if implemented, could achieve these reductions, while improving Americas environment and our energy security.
Global warming is real, is happening now, and poses a serious threat to Americas future.
" Global average temperatures increased by 1Ú F in the 20th century and are now increasing at a rate of about 0.36Ú F per decade. Sea levels are on the rise, ice and snow cover are decreasing, and hurricane intensity has increased.
" The consensus view of the scientific community is that most of the global warming that has occurred is due to human activitiesparticularly the burning of fossil fuels. Fossil fuel consumption releases carbon dioxide, which traps the suns radiation near the earths surface. Since 1750, the concentration of carbon dioxide in the atmosphere has increased by 35 percenta rate of increase unprecedented in the last 20,000 years.
" Should the world continue on its present course, global warming emissions could triple in the next half century, with global temperatures increasing by 8Ú F by 2100. Sea levels would rise by one and a half feet (and possibly more), threatening low-lying coastal areas. And the ecological balance upon which life depends would be irrevocably altered.
The United States has a responsibility to take leadership in reducing global warming pollution.
" The United States is far and away the worlds largest global warming polluter, accounting for 23 percent of the worlds carbon dioxide emissions.
" Should current trends continue, by 2030 the United States will emit 37 percent more carbon dioxide than it does today, increasing the likelihood of dramatic global climate change.
" To avoid the worst consequences of global warming, scientists believe that the United States needs to stabilize emissions within a decade, begin reducing them soon thereafter, and cut global warming pollution by 80 percent by the middle of this century.
The United States can achieve significant reductions in global warming pollution by improving the energy efficiency of our economy and using more renewable energy.
The United States can reduce its global warming emissions by as much as 19 percent by 2020 by taking a set of aggressive but achievable steps toward improved energy efficiency and increased use of renewable energy, within the context of mandatory limits on global warming pollution.
1) Stabilize vehicle travel. Americans drive nearly twice as many miles per year as they did a quarter-century ago, leading to increased emissions of global warming pollutants. Americans are already cutting back on driving as a result of higher gasoline prices, but many Americans have few realistic alternatives to driving. Through changes in public policy and development patterns, Americans can be given more transportation choices, thus reducing the growth in vehicle travel. Such changes include:
o Encouraging the development of compact neighborhoods with a mix of land uses, where more tasks can be completed by foot, bike or transit.
o Expanding the reach and improving the quality of transit service.
o Supporting programs to encourage carpooling, vanpooling, telecommuting and other alternatives to single-passenger car travel.
2) Increase vehicle fuel economy standards to 40 miles per gallon and set fuel economy standards for large trucks. The creation of federal fuel economy standards for cars during the 1970s succeeded in reducing gasoline consumption and oil imports, as well as global warming pollution. But the fuel economy of new vehicles is now lower than it was during most of the Reagan administration.
Several recent studies show that we could increase the fuel economy of new vehicles to 40 miles per gallon within the next decade using technologies that already exist or will be available soon. All types of vehicles from SUVs to compactscan be designed to be far more energy efficient. And most of the improvements in fuel economy can actually save money for consumers over the long term, especially with gasoline prices at nearly $3 per gallon. Similarly, major improvements in fuel economy are possible for heavy-duty trucks, which are currently exempt from fuel economy standards.
3) Replace 10 percent of vehicle fuel with biofuels or other clean alternatives. Ethanol and biodiesel that are produced cleanly and sustainably have the potential to significantly reduce global warming emissions from transportationespecially if these biofuels are produced from plant wastes and cellulose. Other vehicle technologieslike plug-in hybrids, electric vehicles and fuel cell vehicleshave the potential to dramatically reduce global warming emissions in the future.
4) Reduce energy consumption in homes, business and industry by 10 percent from current levels. Dramatic improvements in energy efficiency are possible in virtually every aspect of American life. Studies show that we could reduce our electricity consumption by as much as 20 percent at no net cost to the economy. For now, the U.S. can encourage weatherization of buildings, deployment of more efficient appliances and equipment, and efficiency improvements in industry. Soon, using new technologies such as those in zero-energy homes, we can transform the way we consume energy and achieve even larger improvements in efficiency.
5) Obtain 20 percent of our electricity from new renewable energy sources. America has virtually limitless potential for the generation of power from natural forces. By ramping up our use of wind power, solar power, geothermal and biomass energy and other renewable forms of energyand using much of that energy to replace power production at dirty, coalfired power plantsthe United States could dramatically reduce global warming emissions from electric power production.
6) Hold emissions from other sources to current levels. The five strategies listed above would address the largest sources of energy use and global warming emissions in the United States But some other sources of global warming pollutionsuch as emissions from air travel and emissions of some non-carbon dioxide global warming gasesare projected to increase significantly in the years ahead. The United States must remain vigilant about stabilizing, and eventually reducing, global warming pollution from all sectors of the economy. Mandatory limits on global warming emissions would help to achieve that goal.
These six steps would enable the United States to reduce its global warming emissions by 19 percent below 2004 levels by 2020.
" Taking these six steps would reduce U.S. carbon dioxide emissions by about 23 percent and global warming emissions by about 19 percent by 2020. (See Table ES-1.)
Table ES-1. Global Warming Emission Impact of the Six Steps (million metric tons carbon dioxide equivalent) Strategy Savings MMTCO2E Stabilize Vehicle Travel 0* 40 MPG Fuel Economy and Heavy-Duty Truck Fuel Economy Standards 383 10% of Transportation Fuel from Renewables 61 10% Reduction in Energy Consumption 400 20% of Electricity from New Renewables 511 Total Savings 1355 2004 U.S. Global Warming Emissions 7122 Reduction Relative to 2004 19% * Avoids increase in emissions resulting from projected increases in vehicle travel between now and 2020.
" In addition, taking these steps will reverse the trajectory of global warming emissions, putting the United States on a path to achieving the even greater reductions in global warming pollution that will be required in the decades to come.
The United States should adopt a series of public policies designed to quickly and significantly reduce emissions of global warming pollutants:
Cap global warming emissions. The United States should establish mandatory, science-based limits on carbon dioxide and other global warming pollutants that reduce emissions from todays levels within 10 years, by 15-20 percent by 2020, and by 80 percent by 2050.
Adopt complementary policies to reduce global warming emissions. The United States should adopt policies that would achieve the targets laid out in this report, including, but not limited to:
" Transportation policies designed to reduce growth in vehicle travel and promote alternatives to automobile travel.
" An increase in federal fuel economy standards for cars and light trucks.
" Creation of federal fuel economy standards for heavy trucks.
" A renewable fuel standard requiring a significant share of transportation fuel to come from renewables by 2020.
" Policy support for the development and introduction of plug-in hybrid, electric and fuel-cell vehicles.
" Stronger appliance efficiency standards, energy efficiency programs and other policies designed to improve energy efficiency.
" A federal renewable energy standard requiring a large and increasing share of the nations electricity to come from renewable energy.
Encourage action at the state level. Federal action to reduce global warming pollution should promote innovative approaches at the state level and not impede individual states or groups of states from pursuing policies that go above and beyond the commitments made by the federal government.