The Great Debate

Ahead of a U.N. summit in Copenhagen next month, scepticism is growing that an agreement will be reached on a global climate treaty to replace the Kyoto Protocol, due to expire in 2012.

The protocol set targets aimed at reducing greenhouse gas emissions, which are believed to be responsible for the gradual rise in the Earth's average temperature. Many scientists say that reducing carbon dioxide emissions is key to preventing climate change.

But authors Steven D. Levitt and Stephen J. Dubner argue in their new book SuperFreakonomics that humanity can take an alternative route to try and save the planet.

"If the goal is to stop warming then geo-engineering solutions are worth considering because they are far cheaper, probably much more do-able and easily reversible," Dubner told Reuters before a talk at the Royal Society for the encouragement of Arts, Manufactures and Commerce in London.

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John Chen has served as chairman, chief executive officer and president of Sybase, Inc. since 1998. All views are his own.

As I watched the news showing President Obama reaching out to University of Notre Dame graduates eager to shake his hand, I was impressed by the coalition of colors and nationalities in the faces all round the President that says much good about the United States. I also wondered who, among those shaking President Obama’s hand, will be told by an immigration official next week, ”Congratulations, graduate. Now hit the road, leave the U.S., go home!”

When that happens, if it hasn’t already happened to thousands of graduates across the country, the U.S. will be the loser.