World Leaders Meet on Urgent Climate Change Goals, Paris

U.S. President Barack Obama delivers a speech on the opening day of the World Climate Change Conference 2015 (COP21) in Le Bourget, near Paris, France, November 30, 2015.

U.S. President Barack Obama is seen on a giant screen as he delivers a speech for the opening day of the World Climate Change Conference 2015 (COP21) at Le Bourget, near Paris, France, November 30, 2015.

Zimbabwe's President Robert Mugabe is greeted by French President Francois Hollande, left, as he arrives for the COP21, United Nations Climate Change Conference, in Le Bourget, outside Paris, Monday, Nov. 30, 2015.

ក្មេង​ៗ​ជញ្ជូន​ទឹក​នៅ​ក្នុង​ភូមិ​លេចទឹក​មួយនៅទីក្រុង​ Pansor រដ្ឋ Lanao del Norte ភាគ​ខាងត្បូង​ហ្វីលីពីន។

Anak-anak mengangkut jerigen-jerigen air minum yang ditarik sapi di desa yang hancur akibat banjir bandang di Pansor, Salvador, Lanao del Norte, Filipina selatan.

(L to R) Zimbabwe's President Robert Mugabe, Egyptian President Abdel Fattah el-Sisi (back), Chad's President Idriss Deby, and Benin's President Thomas Boni Yayi pose pose for a family photo during the opening day of the World Climate Change Conference 20

Zimbabwe's President Robert Mugabe arrives for the COP21, United Nations Climate Change Conference, in Le Bourget, outside Paris, Monday, Nov. 30, 2015.

U.S President Barack Obama shakes hands with South Africa's President Jacob Zuma (R) during a family photo for the opening day of the World Climate Change Conference 2015 (COP21) at Le Bourget, near Paris, France, November 30, 2015.

World leaders pose for a family photo during the opening day of the World Climate Change Conference 2015 (COP21) at Le Bourget, near Paris, France, November 30, 2015.

Nigeria's President Muhammadu Buhari delivers a speech for the opening day of the World Climate Change Conference 2015 (COP21) at Le Bourget, near Paris, France, November 30, 2015.

Kenyan President Uhuru Kenyatta delivers a speech for the opening day of the World Climate Change Conference 2015 (COP21) at Le Bourget, near Paris, France, November 30, 2015.

World leaders come together to discuss their goal of curbing fossil fuel emissions and limiting the rise in global temperatures at opening day of the World Climate Change Conference 2015 (COP21) at Le Bourget, near Paris, France, November 30, 2015.