Global Warming

Climate scientists say drastic reductions in greenhouse gas emissions are needed to prevent or delay environmental catastrophe. John McCain and Barack Obama are both strong supporters of a “cap-and-trade” system to reduce carbon dioxide emissions by giving businesses a financial incentive to become greener.

Obama wants to cut carbon emissions to 80 percent below 1990 levels by 2050, while McCain wants a cut to 60 percent below 1990 levels by 2050.

Energy Funding

Both McCain and Obama say they want to dramatically increase investment in renewable sources of energy and technology to reduce emissions from coal-fired power plants, boost tax credits for energy research, and offer federal incentives to develop more fuel efficient vehicles. One major difference: corn-based ethanol. McCain opposes federal subsidies for that bio-fuel, while Obama supports them.

Nuclear Power

A new nuclear power plant has not been built in this country in decades because of safety concerns, but interest in nuclear power has surged in recent years. Nuclear facilities do not release carbon dioxide into the atmosphere, unlike coal-fired power plants, which release thousands of tons of the global-warming gas each year.

McCain wants to speed construction of 45 new plants over the next 25 years. Obama is less enamored with nuclear power. He thinks new nuclear plants should be built, but only if a national plan is developed to safely capture and store waste somewhere other than a controversial site at Yucca Mountain, in Nevada.