Speaking to the BBC, Emma Ruby-Sachs from global campaigning group Avaaz said the display symbolized “an outpouring of determination from Parisians to be heard nonetheless.”

As climate change marches take place in other parts of the world ahead of the summit, campaigners and activists have been sharing their messages of support and solidarity on social media.

COP21, which stands for the 21st Conference of the Parties, runs through Dec. 11. The inaugural COP meeting was held in Berlin in 1995.

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