As my colleague Emily Rauhala wrote earlier today, the northeastern Chinese city of Harbin, close to the border with Russia, is suffering through some truly horrible air pollution. And given that this is mainland China — home to some of the most polluted cities in the world — that’s saying something:

State media said the PM 2.5 reading [which measures the level of harmful particulate matter in the air] ‘exceeded’ 500. A Reuters report put the figure at 1,000, or 40 times higher than what the World Health Organization deems safe. Photographs from the city show air so murky it would be easy to mistake Monday morning for deep, dark night.

The intensification of the smog has to do with weather — as temperatures dip in more northern cities like Harbin, the coal plants that provide most of China’s energy and heat kick into overdrive. (It doesn’t help that in 1950, the Chinese government declared that everyone who lived north of China’s Huai River and Qinling Mountains — which includes major cities like Harbin, Shenyang and Beijing — could receive coal-powered heating for free.) The pollution was so bad that the police had to close off highways and the provincial airport because of accidents, while admissions into Harbin’s hospital spiked because of patients with breathing problems.

None of this is new. Anyone who has spent even a short time in China’s major cities knows the air quality on many days is often worse than the worst you might experience in European or American cities. I got my start as an environment writer almost 10 years ago covering the worsening air pollution in Hong Kong, which was mostly due to emissions from cars, coal plants and factories across the border in China’s bustling Guangdong province. Along with glass-covered skyscrapers and hellish traffic, smog has been the most visible manifestation of the startling economic growth China has experienced over the past quarter-century.

It’s hard to know for sure whether air pollution in China’s cities really is getting worse — the data from the central government can be less than credible, so much so that Beijingers came to rely on the U.S. embassy, which tweets out daily air-quality readings from its own sensors. But what’s clear is that awareness of the bad air is rising, even as Chinese citizens have become more emboldened — and more able, thanks to the rise of microblogging services — to complain about environmental problems. During the first six months of the year — which began with reports of an “airpocalypse” in Beijing — foreign visitors to China fell by 5% over the same period of time from the previous year, and the number of tourists visiting Beijing fell by 15%. Concerns over H7N9 bird flu may have played a role, but the idea that China is literally hazardous to your health can’t help either.

At least foreign visitors have a choice. Chinese citizens have to live in polluted cities like Lanzhou, Xining and Jinan, cities where particulate readings are at least six times higher than the target set by WHO guidelines. The health effects are dangerous — researchers estimated that the half a billion people in northern China will live an average of 5½ years less than their southern counterparts, thanks to the thick air pollution in the north. Just last week, the WHO declared that air pollution is officially a carcinogen, and a leading environmental cause of cancer. The 2010 Global Burden of Disease study found that air pollution accounted for 1.2 million premature deaths in 2010. Even as China’s citizens get richer, air pollution will ensure that they get sicker too.

The silver lining in the smog is that China’s government is beginning to get serious about cleaning the air, thanks in no small part to popular anger from average Chinese. (One line from China’s popular Twitter-like site Sina Weibo captured the sarcastic discontent in Harbin: “After years of effort, the wise and hardworking people of Harbin have finally managed to skip both the middle-class-society and the communist-society stages, and have now entered a fairyland society!”) Earlier this month the Chinese government announced that it would give rewards amounting to more than $800 million for reducing air pollution in six regions in the north. And in September the government unveiled a plan to reduce air pollution nationwide by putting limits on coal burning and taking high-polluting vehicles off the roads on certain days.

But like so much else in China, the success of the new regulations will depend on whether officials at the provincial and city level — where ensuring economic growth is still seen as the prime directive and the best way to guarantee career advancement — actually implement them. And if China really intends to clean up its air, it needs to reduce demand for coal and switch to cleaner sources of energy. There are already signs that the Chinese hunger for coal is slowing down, along with the country’s economy — and tougher environmental regulations could curb that even further. But unlike the U.S., which has been able to use cheap and clean shale gas in place of coal, China is still years away from developing unconventional gas. Which means the skies over cities like Harbin could stay smoggy for years.