LI MIN/CHINA DAILY The Climate Ambition Summit 2020 held on Dec 12 will not only help unite the world to fight the greatest challenge facing our planet, but also stabilize the turbulent relationship between China and the United States after Joe Biden is sworn in as US president on Jan 20. At the virtual summit, attended by governmental and nongovernmental leaders on the 5th anniversary of the Paris Agreement, President Xi Jinping announced that China will reduce its carbon dioxide emissions per unit of GDP by more than 65 percent by 2030 from the 2005 levels while greatly increasing the share of non-fossil fuels in primary energy consumption, forest stock and installed wind and solar power capacity. In late September, Xi had already pledged that China's carbon emission will peak before 2030 and the country will achieve carbon neutrality before 2060.Despite facing huge challenges as the largest developing country, China has forged ahead on the environmental front. It is by far the largest wind and solar power producer in the world and has the highest numbers of electric buses and cars. China has made these achievements despite US President Donald Trump quitting the landmark Paris accord and rolling back many climate policies introduced by the Barack Obama administration. The trade and technology wars Trump has launched, and the other unilateral and protectionist measures he has taken have created major hurdles for the climate fight in China and many other countries, as they have disrupted other countries' supply chains and created trade barriers. Biden's pledge to rejoin the Paris accord and convene the leaders of major economies for a climate summit within his first 100 days in office is indeed an encouraging sign. His climate envoy John Kerry, who was secretary of state during the Obama presidency, described China as a "climate partner" last week. The incoming US administration has a lot to do to correct the course and rebuild the US' credibility in the world, because the Trump administration's measures have undermined the global fight against climate change over the past almost four years. One concern is the sharp partisan division over the issue. According to a Pew survey in June, 72 percent Democratic Party leaders and supporters believe that human activity is mainly responsible for the climate change while only 22 percent of Republicans and Republican supporters believe so. The fact that Trump, a climate denier, won more than 73 million popular votes in the recently concluded presidential election is a cause for concern. Indeed, China and the US, the world's two largest economies, should again join hands in the fight against climate change, because it is a far greater threat to both countries than their many differences. That said, the US is by far the biggest historical emitter, and its per capita emission is still more than twice that of China's. The European Union, another major historical emitter, is aspiring to be a global leader in the fight against climate change. In survey after survey, most European countries have listed climate change as the single biggest threat, even bigger than the COVID-19 pandemic. China and the EU agreed in September to launch a "high-level environment and climate dialogue" to pursue joint commitments in the fight against climate change. And on Saturday, UN Secretary-General Antonio Guterres said that the central objective of the UN in 2021 will be to build a truly global coalition for carbon neutrality by the middle of the century. It's hard to believe that such a coalition would even exist without the genuine and full cooperation between China, the US and the EU. And it means they should cease or at least drastically lower the temperature of geopolitical rivalries triggered by some politicians and the military industrial complex. Otherwise, the global battle against climate change is doomed to failure. The author is chief of China Daily EU Bureau based in Brussels.email@example.com If you have a specific expertise and would like to contribute to China Daily, please contact us at firstname.lastname@example.org, and email@example.com.