A woman walks past a map showing the elevation of the sea in the last 22 years during the World Climate Change Conference 2015 (COP21) at Le Bourget, near Paris December 11, 2015. REUTERS/Stephane Mahe 

Hundreds of environmentalists arrange their bodies to form a message of hope and peace in front of the Eiffel Tower in Paris, France, December 6, 2015, as the World Climate Change Conference 2015 (COP21) continues at Le Bourget near the French capital. REUTERS/Benoit Tessier 

A participant wearing a virtual reality headset attends the World Climate Change Conference 2015 (COP21) at Le Bourget, near Paris, December 8, 2015. REUTERS/Stephane Mahe 

A particiapant holds a piggy bank as she looks for contributions during the World Climate Change Conference 2015 (COP21) at Le Bourget, near Paris December 10, 2015. REUTERS/Stephane Mahe 

A replica Statue of Liberty is displayed with a smoke trailing from its torch during a street parade as part of the "Global Village of Alternatives" events held in Montreuil, near Paris, France, December 5, 2015 as the World Climate Change Conference 2015 (COP21) continues at Le Bourget near the French capital. REUTERS/Benoit Tessier 

A participant holds an apple marked with the logo of the World Climate Change Conference 2015 (COP21) during a meeting at Le Bourget, near Paris, France, December 7, 2015. REUTERS/Stephane Mahe 

Visitors and ecological stands are reflected on a giant ball suspended from the roof of the Grand Palais during the Solutions COP21 in Paris, France, December 4, 2015 as the World Climate Change Conference 2015 (COP21) continues at Le Bourget near the French capital. REUTERS/Benoit Tessier 

A Greenpeace activist hangs with a banner reading "Mister Hollande, renew energy" from the top of the Arc de Triomphe during a protest on the Champs Elysees avenue in Paris, France, December 11, 2015 as part of the World Climate Change Conference 2015 (COP21). REUTERS/Charles Platiau 

People gather at the Place to B, in Paris, France, December 9, 2015, as the World Climate Change Conference 2015 (COP21) continues at Le Bourget near the French capital. REUTERS/Benoit Tessier 

Visitors walk through ice blocks harvested in Greenland and installed on the Place du Pantheon for a project called Ice Watch Paris, in Paris, France, December 3, 2015 as the World Climate Change Conference 2015 (COP21) continues at Le Bourget near the French capital. REUTERS/Benoit Tessier 

A tree is pictured at the World Climate Change Conference 2015 (COP21) at Le Bourget, near Paris, December 9, 2015. REUTERS/Stephane Mahe 

People set-up a pannel during the World Climate Change Conference 2015 (COP21) at Le Bourget, near Paris, December 9, 2015. REUTERS/Stephane Mahe 

Participants are seen in silhouette as they look at a screen showing a world map with climate anomalies during the World Climate Change Conference 2015 (COP21) at Le Bourget, near Paris, December 8, 2015. REUTERS/Stephane Mahe