From his speech today in Portland, OR:

Some of the most compelling evidence of global warming comes to us from NASA. No longer do we need to rely on guesswork and computer modeling, because satellite images reveal a dramatic disappearance of glaciers, Antarctic ice shelves and polar ice sheets. And I've seen some of this evidence up close. A few years ago I traveled to the area of Svalbard, Norway, a group of islands in the Arctic Ocean. I was shown the southernmost point where a glacier had reached twenty years earlier. From there, we had to venture northward up the fjord to see where that same glacier ends today – because all the rest has melted. On a trip to Alaska, I heard about a national park visitor's center that was built to offer a picture-perfect view of a large glacier. Problem is, the glacier is gone. A work of nature that took ages to form had melted away in a matter of decades.

To lead in this effort, however, our government must strike at the source of the problem – with reforms that only Congress can enact and the president can sign. We know that greenhouse gasses are heavily implicated as a cause of climate change. And we know that among all greenhouse gasses, the worst by far is the carbon-dioxide that results from fossil-fuel combustion. Yet for all the good work of entrepreneurs and inventors in finding cleaner and better technologies, the fundamental incentives of the market are still on the side of carbon-based energy. This has to change before we can make the decisive shift away from fossil fuels.

We will cap emissions according to specific goals, measuring progress by reference to past carbon emissions. By the year 2012, we will seek a return to 2005 levels of emission, by 2020, a return to 1990 levels, and so on until we have achieved at least a reduction of sixty percent below 1990 levels by the year 2050. In the course of time, it may be that new ideas and technologies will come along that we can hardly imagine today, allowing all industries to change with a speed that will surprise us. More likely, however, there will be some companies that need extra emissions rights, and they will be able to buy them. The system to meet these targets and timetables will give these companies extra time to adapt – and that is good economic policy. It is also a matter of simple fairness, because the cap-and-trade system will create jobs, improve livelihoods, and strengthen futures across our country.

As we move toward all of these goals, and over time put the age of fossil fuels behind us, we must consider every alternative source of power, and that includes nuclear power. When our cap-and-trade policy is in place, there will be a sudden and sustained pursuit in the market for new investment opportunities in low-emission fuel sources. And here we have a known, proven energy source that requires exactly zero emissions. We have 104 nuclear reactors in our country, generating about twenty percent of our electricity. These reactors alone spare the atmosphere from about 700 million metric tons of carbon dioxide that would otherwise be released every year. That's the annual equivalent of nearly all emissions from all the cars we drive in America. Europe, for its part, has 197 reactors in operation, and nations including France and Belgium derive more than half their electricity from nuclear power. Those good practices contribute to the more than two billion metric tons of carbon dioxide avoided every year, worldwide, because of nuclear energy. It doesn't take a leap in logic to conclude that if we want to arrest global warming, then nuclear energy is a powerful ally in that cause.

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