The United Nations Climate Change Conference (Cop15) turned ugly today when police officers beat back hundreds of demonstrators, including a group of 50 to 100 delegates that were trying to meet with the protesters.

More than 250 people were arrested, including spokespeople for Climate Justice Action (CJA), a global network of NGOs that organized a walkout at the Bella Center today. CJA’s spokesperson Dan Glall told Mantoe Phakathi at Inter Press Service that “as a condition for going back to the negotiations, we demand industrialized nations uphold the Kyoto Protocol, commit adequate funds to adaptation and reduce greenhouse gas emissions significantly.”

OneClimate has video (below) of today’s walkout.

“More than 1,000 people have been arrested, detained and released over the course of the past week,” Jennifer Prediger writes for Grist. “Some were made to sit on freezing sidewalks for six hours in a nasty version of time out. The people who threw rocks and set cars on fire were rightfully detained.  But the droves who were dragged in last night for dancing awkwardly in Christiana?  Seems like overkill to me.”

The chaos outside reflects the increasing pressure inside the Bella Center, as delegates turn to the United States and China for leadership in the final days of the summit. Together these countries account for 42 percent of the world’s carbon emissions.

In order to finalize a global climate agreement in Copenhagen, both countries need to take a big step forward, as David Doniger and Barbara Finamore report for Grist. For the U.S., this means aid for the world’s poorest and most vulnerable people; for China, this means making steady progress to meet the country’s carbon reduction goals.

The U.S. has already committed to pay its share of a $30 billion fund to last through 2012. “But to lead in Copenhagen, the U.S. needs to back even larger investments to meet these core needs for the longer-term—2015 or 2020,” Doniger and Finamore write. “China has the opportunity to enhance its standing as a responsible world leader by building global confidence in the implementation of its carbon reduction goals.”

But as David Corn reports for Mother Jones, China and the U.S. are apparently “stuck in a standoff.” An Obama administration official insisted that it’s not about the money: “‘We have to get the developing nations into an international agreement,’ the official said… Yet China has forcefully resisted the idea of incorporating their self-professed emissions goals (essentially, slowing the growth rate of emissions) into a binding agreement. China has also repeatedly said that it will not submit its performance to official outside vetting.”

Corn writes, “But with 115 heads of states beginning to arrive, the Copenhagen talks have left some fundamental gaps for the last minute. Even if those gaps are bridged, the resulting agreement could fall far short of what experts say is necessary to redress the dire consequences of rising global temperatures. Just ask the scientists roaming the halls.”

Secretary of State Hillary Clinton arrived in Copenhagen today in a last minute appearance. Clinton has booked a full day of meetings on Thursday and will join President Barack Obama in negotiations when he arrives Friday. Like Obama’s schedule switch at the conference (he originally planned to be there last week and instead will arrive Friday), Clinton’s arrival could indicate the U.S.’s intention to seal a deal by the end of the week.

For live updates of the negotiations and protests, check out The Uptake’s live video stream from the Bella Center.

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