Time to turn up the heat on action

Climate crisis leaves no room for complacency

The past three years have been the hottest on record. Research shows that such extreme heat is virtually impossible without warming caused by humans. With modest assistance from El Nino, the continued burning of fossil fuels made this possible.

The World Meteorological Organization estimates that there is an 86 percent likelihood that this temperature record will be broken within the next five years. With another El Nino event brewing in the tropical Pacific, that new record could be set as early as next year. The planet will keep getting warmer as long as we keep releasing carbon pollution by burning fossil fuels for energy and transportation.

Global average temperature, however, is an abstract measure. We do not "feel" it. What we experience instead are the consequences of that warming, particularly the role that warming plays in intensifying extreme weather events that we are witnessing across the world.

Whether it was record-breaking stifling May heat in Philadelphia, the United States, a few weeks ago and in Europe over the past week, or the deadly floods and landslides in central and southwestern China in recent days, the consequences of climate change are now upon us.

Climate science deniers like to cite scientific uncertainty as a reason for not taking action. But the cost of inaction is far greater. Research shows that climate models may be underestimating the extent to which climate change influences extreme weather disasters. They may also be underestimating the potential impact of global warming on ice sheet disintegration, rising sea levels and the occurrence of deadly typhoons.

The question is no longer whether climate change is a threat. The question is how severe we are willing to allow that threat to become. The case for urgency is clear.

Equally important is the recognition that it's not too late to act. A recent study, which was widely misrepresented by opponents of climate action, showed that the efforts underway to transition toward clean energy are paying dividends. The world is making real progress in lowering emissions that lead to climate change.

A decade ago, worst-case emissions scenarios projected catastrophic warming of 4 C to 5 C by the end of this century. Today, those projections have reduced to 3.5 C to 4 C. Even a "business-as-usual" scenario, where no further policy action is taken, would likely lead to around 3 C warming, still dangerous but considerably less than what we faced just a decade ago. This improvement reflects the policy progress the world has made.

But even a 3 C increase is a very dangerous level of planetary warming, which could lead to potentially irreversible climate impacts. We have made progress, but it is not nearly enough.

Part of the problem is that the US, once a leader in climate action, is now backsliding under its current leadership. The bilateral climate agreement between China and the US during the Barack Obama administration set the stage for the landmark Paris Agreement in 2016.

Since then, only China has made good on its end of the bargain. In 2014, it promised to peak carbon emissions before 2030. Driven by an expansion in renewable energy deployment, including wind, solar, battery technologies, electric vehicles and high-speed rail, China's carbon emissions have entered a "flat or falling" trend well before the 2030 deadline.

In 2025, renewable energy accounted for nearly 86 percent of newly added power generation and reached nearly 50 percent of installed power capacity worldwide. The leading US scientific journal, Science, named the renewable energy surge as the 2025 Breakthrough of the Year. It singled out China's role: "China's mighty industrial engine is the driver. After years of patiently nurturing the sector through subsidies, China now dominates global production of renewable energy technologies."

In contrast, the US is moving in the opposite direction. The current US administration and its Republican supporters have rejected global climate agreements, partnered with oil-producing countries and doubled down on fossil fuel extraction, thereby sabotaging clean energy efforts.

The US once prided itself on being the hub of technological innovation. That honor has now shifted to China. Chinese automaker BYD has developed technology that charges EV batteries to 97 percent capacity in just 12 minutes even in freezing temperatures, putting the US EV industry to shame. The Chinese all-electric and now largely renewable-driven bullet trains are breaking records both for usage and speed. More than 4 billion passenger trips were made on the network in 2025, and trains routinely move at speeds of 350 kilometers per hour. Meanwhile, the US national rail service, Amtrak — long underfunded and under assault from fossil-fueled Republicans — languishes with aging equipment. Its flagship Acela high-speed service struggles to maintain an average speed of 132 km per hour.

The US is no longer the conductor of the bullet train that is the global clean energy revolution. It should decide whether to climb on board or get left behind at the station. The rest of the world, and China in particular, should remain resolute in moving toward a global clean energy economy. The stakes could not be higher.

The author is the presidential distinguished professor of earth and environmental science at the University of Pennsylvania.

The author contributed this article to China Watch, a think tank powered by China Daily. The views do not necessarily reflect those of China Daily.

Contact the editor at editor@chinawatch.cn.