BEIJING - Record heat and historic floods in China this summer have failed to ignite domestic public debate about how the world's top carbon polluter can mitigate climate change, leaving campaigners frustrated at an opportunity missed.

While state media and officials have said in the past that climate change makes China more vulnerable to extreme weather, few have made the connection this year, and have been even more reluctant to link it to China's own emissions - now around a third of the global total and rising.

"I actually see that as a big missed opportunity, actually, for the Chinese government to garner enough social support for its climate agenda," Li Shuo, senior adviser with Greenpeace in Beijing, said.

"And at the very minimum to reach a sort of a new narrative that is closer to the reality on the ground."

There was no major spike in searches for climate change in recent weeks on either the popular Weibo microblog platform or China's biggest search engine, Baidu, according to their official search indexes. That's despite widespread discussion about severe weather, in which at least 33 people died in Beijing alone.

Several residents in Beijing and flooded areas in surrounding Hebei province said that they were aware of changing climate trends, but were reluctant to say more.

"Extreme weather, nowadays, is becoming more frequent," said a 53-year-old resident in the Hebei city of Zhuozhou, who gave his name only as Su.

"We can't comment on that. We're not the authorities. The summers are hotter than before, the winters are not as cold as before," said Su, whose crops and home were damaged by the floods.

A Baidu search for the question "should China be more responsible for climate change?", or variations of it, did not produce any articles critical of China's climate policy in the first few dozen results.

Instead, the results, many from state media outlets, focused on China's leadership in the fight against climate change and calls for developed countries to take more responsibility.

China's foreign ministry did not immediately respond to a request for comment on this story, but government spokespeople have long defended China's record on climate change and press freedom.

In developed countries, environment campaigners are also anxious as governments, seeking to be re-elected, have lowered climate ambitions in response to a backlash from those resistant to the life-style changes needed to curb emissions.

TOP-DOWN

China in principle is well-placed to impose top-down, state-led campaigns that support government policy that could make it a climate action leader.

But Fang Kecheng, from the Chinese University of Hong Kong, who published a paper on what he termed Beijing's "authoritarian environmentalism" in June, said climate messaging was used differently.

"Like many other issues in China, climate change basically is used as an issue by media to glorify the state and the supreme leader and also to attack the United States and other western countries," he said.

This has not always been the case. Around a decade ago, a grassroots-led campaign on air pollution prompted China's leaders to clean up its smog-filled skies, especially in the capital Beijing.

Professor of Communications at the University of Wisconsin-Madison, Pan Zhongdang, said part of the issue was fear of what could be unleashed by freedom of expression.

"It doesn't have minimum self confidence to allow for debate or discussion," he said of the Chinese government.

A crackdown on NGOs, civil society and media freedoms under President Xi Jinping has made any grassroots climate change very unlikely, forcing campaigners to adapt and try instead to influence an increasingly centralised leadership.

"I think, in general, this seems to be a situation where they have kept sort of a very tight lid on freedom of speech to the point where they don't even know how to walk back," said Yifei Li, assistant professor of Environmental Studies at New York University's Shanghai Campus.

China has set some bold green targets, including Xi's pledge to make the country carbon neutral by 2060, but experts want Beijing to act faster, and worry that the failure to engage the public could slow the transition.

China's CO2 emissions grew 10% in the first quarter of 2023 from a year earlier, rising by approximately 1% above record levels in 2021, according to research by the Centre for Research on Energy and Clean Air (CREA) on Thursday.

Despite the extreme weather, China has reinforced its message about energy security rather than climate change in recent months, said CREA's lead analyst, Lauri Myllyvirta.

"In this context, emphasising the role of China's emissions, even to say that there are policies in place to bring them down, would not fit the narrative and might hit too close to home," he said.

(Additional reporting by the Shanghai and Beijing Newsroom; Editing by David Stanway and Barbara Lewis)