UN Secretary Ban Ki-moon at a press conference in Hangzhou on September 4 (LIU YUNYUN)

China and the United States may disagree on many things, but climate change isn't one of them.

On September 3, just prior to this year's G20 Summit in Hangzhou, Chinese President Xi Jinping and U.S. President Barack Obama handed their nations' ratification documents of the Paris Agreement on Climate Change to UN Secretary General Ban Ki-moon.

The move shows the world's two largest carbon emitters, who jointly account for 38 percent of global emissions, have come together to enforce the Paris deal in order to make the world less hazardous for future generations.

Some U.S. Senate members, however, still question Obama's use of an executive order to "ratify" the agreement and have threatened to repeal it. Republican presidential candidate Donald Trump has openly stated his opposition to the accord and said he would "cancel" the agreement.

The UN chief commended both nations' commitment to curbing carbon emissions and said they will serve as an example for other countries to follow suit. He told Beijing Review that climate change skepticism and controversy have already ended due to concrete scientific evidence.

When asked whether signatories to the accord that fail to implement it will be punished, Ban said nations which implement climate change policies will reap "more rewards" and that "early actions" will benefit humanity's well-being to a greater degree and are conducive to the common good. "The 2030 Sustainable Development Goals and climate change are interlinked. If one country only focuses on social policies, it may have short-term gain but may have serious long-term problems," Ban said.

Chinese President Xi said, "Only commitment and decision will lead to great achievement." China has been active in developing clean energies. According to the 2016 Global New Energy Development Report, published at a forum in April this year, China has ranked first for four consecutive years since 2012 on clean energy investment. In 2015 alone, China's investment in clean energy reached $111 billion, accounting for 33.6 percent of the world's total and almost equaling the combined investment by the United States and the EU.

The Paris Agreement on Climate Change was signed in December last year in the French capital by more than 190 countries with the goal of keeping global temperature growth below 2 degrees Celsius compared with pre-industrial levels.

(Reporting from Hangzhou)

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