Official positions of Obama and Romney on climate change

From a questionnaire produced by sciencedebate.org:

Question: Climate Change. The Earth’s climate is changing and there is concern about the potentially adverse effects of these changes on life on the planet. What is your position on cap-and-trade, carbon taxes, and other policies proposed to address global climate change—and what steps can we take to improve our ability to tackle challenges like climate change that cross national boundaries?
Barack Obama: Climate change is the one of the biggest issues of this generation, and we have to meet this challenge by driving smart policies that lead to greater growth in clean energy generation and result in a range of economic and social benefits. Since taking office I have established historic standards limiting greenhouse gas emissions from our vehicles for the first time in history. My administration has made unprecedented investments in clean energy, proposed the first-ever carbon pollution limits for new fossil-fuel-fired power plants and reduced carbon emissions within the Federal Government. Since I took office, the U.S. is importing an average of 3 million fewer barrels of oil every day, and our dependence on foreign oil is at a 20-year low. We are also showing international leadership on climate change, reaching historic agreements to set emission limits in unison with all major developed and developing nations. There is still more to be done to address this global problem. I will continue efforts to reduce our dependence on oil and lower our greenhouse gas emissions while creating an economy built to last. Additional questions for Obama: 1. What specific "economic and social benefits" have your "smart policies" provided? 2. What evidence do you have to support your claim that the trace, essential gas carbon dioxide, 96% of which is produced by nature, is "pollution"? 3. Regarding the 3 million fewer barrels of oil imports, how many are due to economic contraction, and how many are due to new fracking technology developed by the domestic oil industry without your help? 4. What "historic agreements to set emission limits in unison with all major developed and developing nations" have you reached? Why did you skip the Rio+20 Earth Summit on what you claim is "one of the biggest issues of this generation."?		Mitt Romney: I am not a scientist myself, but my best assessment of the data is that the world is getting warmer, that human activity contributes to that warming, and that policymakers should therefore consider the risk of negative consequences. However, there remains a lack of scientific consensus on the issue — on the extent of the warming, the extent of the human contribution, and the severity of the risk — and I believe we must support continued debate and investigation within the scientific community. Ultimately, the science is an input to the public policy decision; it does not dictate a particular policy response. President Obama has taken the view that if global warming is occurring, the American response must be to slash carbon dioxide emissions by imposing enormous costs on the U.S. economy. First he tried a massive cap-and-trade bill that would have devastated U.S. industry. When that approach was rejected by Congress, he declared his intention to pursue the same course on his own and proceeded through his EPA to impose rules that will bankrupt the coal industry. Nowhere along the way has the President indicated what actual results his approach would achieve — and with good reason. The reality is that the problem is called Global Warming, not America Warming. China long ago passed America as the leading emitter of greenhouse gases. Developed world emissions have leveled off while developing world emissions continue to grow rapidly, and developing nations have no interest in accepting economic constraints to change that dynamic. In this context, the primary effect of unilateral action by the U.S. to impose costs on its own emissions will be to shift industrial activity overseas to nations whose industrial processes are more emissions-intensive and less environmentally friendly. That result may make environmentalists feel better, but it will not better the environment. So I oppose steps like a carbon tax or a cap-and-trade system that would handicap the American economy and drive manufacturing jobs away, all without actually addressing the underlying problem. Economic growth and technological innovation, not economy-suppressing regulation, is the key to environmental protection in the long run. So I believe we should pursue what I call a “No Regrets” policy — steps that will lead to lower emissions, but that will benefit America regardless of whether the risks of global warming materialize and regardless of whether other nations take effective action. For instance, I support robust government funding for research on efficient, low-emissions technologies that will maintain American leadership in emerging industries. And I believe the federal government must significantly streamline the regulatory framework for the deployment of new energy technologies, including a new wave of investment in nuclear power. These steps will strengthen American industry, reduce greenhouse gas emissions, and produce the economically-attractive technologies that developing nations must have access to if they are to achieve the reductions in their own emissions that will be necessary to address what is a global issue.