No details yet, but President Obama says a "meaningful" climate deal has been reached between the US, China, India, Brazil, and South Africa. The deal has no emissions cap but sets a goal of limiting global warming to two degrees Celsius. On the one hand, this is great news given the deadlock that gripped these countries over the past few days. On the other hand, it sounds like the deal is pretty weak and may not do nearly enough to combat climate change. I take heart in the fact that this is merely "politically" binding. After US legislation passes, we'll see if the "legally" binding treaty that comes out of Mexico City next year is any tougher.

It was Obama's arrival, speech, and personal diplomacy that led to the deal, which while weak is better than no deal at all. You can argue that no Senate bill would be fine since the EPA would step into the void, but there is no global EPA to take COP15's place. I have to wonder, however, how much stronger the deal would have been if the president's deal-making presence had been there all along. Opportunity lost? Probably not, since Mexico City still looms. Anyway, from Politico:

"[A] meaningful agreement was reached," the official said. "It's not sufficient to combat the threat of climate change but it's an important first step... No country is entirely satisfied with each element, but this is a meaningful and historic step forward and a foundation from which to make further progress."

The official added: "We entered this negotiation at a time when there were significant differences between countries. Developed and developing countries have now agreed to listing their national actions and commitments, a finance mechanism, to set a mitigation target of 2 degrees Celsius and to provide information on the implementation of their actions through national communications, with provisions for international consultations and analysis under clearly defined guidelines."

It's not clear how many nations -- particularly poorer nations who felt shut out of the process -- were included in the final deal or how they will react to the announcement.

Earlier Friday, a visibly angry Barack Obama threw down the gauntlet at China and other developing nations Friday, declaring that the time has come "not to talk but to act" on climate change.

Obama's public ultimatum kicked off a furious round of bilateral negotiations between the world's two largest pollution emitters as the conference entered its final hours, with Obama plunging into a pair of bargaining sessions involving Chinese Premier Wen Jiabao, who had earlier boycotted a larger, multi-nation meeting with Obama.

No reaction yet from the expert-written climate blogs I regularly check.

Update 5:50 EST by Nathan Empsall: Obama has already left Copenhagen due to the immense snowstorm heading DC's way. Sounds fun; wish I was there (in Copenhagen or the DC snow, either one.) More importantly, though, reactions to the climate deal are slowly beginning to trickle in. 350.org tweets, "A tweet cannot express the level of frustration & disappointment I feel w/Obama right now. So much for change." Still waiting to hear from Real Climate and Climate Progress, or from an environmental group on a platform of more heft than Twitter.

Update 6:09 EST by Nathan Empsall: The Sierra Club has a decidedly more positive take than 350. Their headline is "President Obama Leads World to Historic, If Incomplete Climate Deal." I am inclined to agree with Executive Director Carl Pope's statement:

"The world's nations have come together and concluded a historic--if incomplete--agreement to begin tackling global warming. Tonight's announcement is but a first step and much work remains to be done in the days and months ahead in order to seal a final international climate deal that is fair, binding, and ambitious. It is imperative that negotiations resume as soon as possible.

President Obama and the rest of the world paid a steep price here in Copenhagen because of obstructionism in the United States Senate. That a deal was reached at all is testament to President Obama's leadership--all the more remarkable because of the very weak hand he was dealt because of the Senate's failure to pass domestic clean energy and climate legislation. Now that the rest of the world--including countries like China and India--has made clear that it is willing to take action, the Senate must pass domestic legislation as soon as possible. America and the world can no longer be held hostage to petty politics and obstructionism...

"The agreement reached here has all the ingredients necessary to construct a final treaty--a mitigation target of 2 degrees Celsius, nationally appropriate action plans, a mechanism for international climate finance, and transparency with regard to national commitments. President Obama has made much progress in past 11 months and it now appears that the U.S.--and the world--is ready to do the hard work necessary to finish what was started here in Copenhagen.