Obama raced clock, chaos, comedy for climate deal

Barack Obama didn't pause, however. "I'm going to sit by my friend Lula," he said, moving toward Brazilian President Luiz Inacio Lula da Silva.

A Brazilian aide gave the U.S. president his chair, and Obama spent the next 80 minutes helping craft new requirements for disclosing efforts to fight global warming. Along with India, South Africa and Brazil, the key member in the room was China, which recently surpassed the U.S. as the world's top emitter of heat-trapping gasses.

At the table this time for China was Premier Wen Jiabao, not an underling as before. Obama was bent on striking a deal before flying home to snowbound Washington.

He would later hail the achievement as a breakthrough. But even Obama said there was much more to do, and climate authorities called Copenhagen's results a modest step in the global bid to curb greenhouse gasses that threaten to melt glaciers and flood coastlines.

Obama's 15-hour, seat-of-the-pants dash through Copenhagen was marked by doggedness, confusion and semi-comedy. Constrained by partisan politics at home, and quarrels between rich and poor nations abroad, he was determined to come home with a victory, no matter how imperfect.

Experts and activists may debate its significance for years. Some, like Jeremy Symons, who watched the talks for the National Wildlife Federation, said it was "high drama and true grit on the part of the president that delivered the deal."

Others were far less kind. The Copenhagen agreements are "merely the repackaging of old and toothless promises," said Asher Miller, executive director of the Post Carbon Institute.

Even though a weary, bleary-eyed Obama had added six hours to his planned nine-hour visit, he was back in Washington by the time delegates at the 193-nation summit approved the U.S.-brokered compromises on Saturday. The agreements will give billions of dollars in climate aid to poor nations, but they do not require the world's major polluters to make deeper cuts in their greenhouse gas emissions.

This account of Obama's hectic day is based on dozens of interviews and statements by key players from numerous countries.