Some 20,000 pairs of empty shoes were lined up in downtown Paris ahead of the start of international climate negotiations Sunday, filling in for global warming protesters who were not permitted to march because of security after this month's attacks. The footwear ranged from high heels to boots, and included a pair of shoes sent by the Vatican on behalf of Pope Francis, reports Reuters. Instead of protests, environmental advocacy groups held marches outside of Paris and around the world. A nearly empty conference center seemed to have more security guards than negotiators as country delegations and media started dribbling into the venue where two weeks of intense talks are expected. Formal negotiations between lower level officials are scheduled to begin late Sunday.
On Monday, more than 140 leaders are expected to arrive, including leaders of the United States, China, and Russia, to talk about their commitment to fight climate change and reduce ever-rising carbon dioxide emissions. The climate negotiations happen as weather officials across the globe proclaim that this is the hottest year on record. And they say that Earth has crossed some significant thresholds in climate. The world has warmed by almost 2 degrees Fahrenheit since pre-industrial times and carbon dioxide levels now are pretty much permanently above the 400 parts per million mark, scientists say. Armed security was noticeable nearly everywhere at the Le Bourget center where negotiations will take place. (Read more Paris stories.)