Following the “airpocalypse” in the city of Harbin this week, a question now hovers in the minds of many residents across northern China. It was summed up in a headline that ran on Thursday with a commentary in People’s Daily, the Communist Party mouthpiece: “In this season of central heating, will PM 2.5 drop?”

PM 2.5 is shorthand for the fine, invisible particulate matter that scientists consider among the deadliest of pollutants — it can penetrate deep into the lungs and enter the bloodstream. The smog that enveloped Harbin and other parts of northeastern China in a spectacular gray haze has made many Chinese fearful of what will happen when other cities start switching on central heating, much of it coal-powered. Following a central government decree from decades ago, cities north of the Huai River provide central heating in winter months. A study published in July by The Proceedings of the National Academy of Sciences, a prominent American journal, concluded that this policy had resulted in the life spans of Chinese living north of the Huai being shortened on average by five years because of pollution generated by the coal used in heating.

As the surge in pollution in Harbin showed, the use of such central heating remains a major factor in air quality, even though officials have been trying to diminish the role of coal in energy production. On Monday and Tuesday, air-quality monitoring stations in some parts of Harbin reported concentrations of PM 2.5 exceeding 1,000 micrograms per cubic meter — at the top of the measurement scale, and 40 times the limit deemed safe by the World Health Organization. The pollution was attributed to the unfortunate convergence of several factors: weather patterns, post-harvest fires on farms and local governments switching on cities’ central heating. People have called it the first “airpocalypse” of the season, similar to the one that hit Beijing, Tianjin, Hebei Province and other parts of northern China last January.

The People’s Daily commentary on Thursday said that Beijing, Tianjin and other areas of northern China had the day before activated an “air pollution coordination control mechanism.” That presumably refers to elements of a broad plan announced by the State Council in September that requires, among other things, three heavily industrialized and populated regions in China to reduce coal use and levels of pollutants within the next several years. The Beijing-Tianjin-Hebei area is required to bring PM 2.5 levels down 25 percent from 2012 levels. It is the most polluted region in China, and it also happens to be where Chinese leaders and their families live.

Environmental advocates have praised the State Council plan for laying out requirements for entire regions, since it is obvious that pollution is generated on a region-wide basis — what one factory emits in Shandong Province or Inner Mongolia contributes to the degraded air in Beijing. People’s Daily said, “Now there is a consensus that no one single area can do well in the face of air pollution from overlapping regions.” And the “first test” of the regional coordination plan, it said, will be whether levels of PM 2.5 drop this winter and early spring, despite the use of central heating.

Environmental advocates say one of the toughest tasks will be getting local officials in the provinces and companies to comply with curbs on coal use. “The local governments in general still want growth,” Ma Jun, an environmental advocate in Beijing, said in an interview on Wednesday.

The People’s Daily commentary also provided some statistics aimed at inspiring optimism in people anxious about the air quality this coming winter: This year, 44,000 homes have switched from using individual coal-powered heating to electric heating; 184 heavily polluting factories have been shuttered, with perhaps another 207 to follow before the end of the year; and 247,000 vehicles have been upgraded with cleaner technology.

The effectiveness of those measures will be judged by those living in northern China, whether they are ordinary citizens or Communist Party leaders. This month, residents of Beijing have already suffered through several days of hazardous air. I will be going online every day this winter, as I do now, to check levels of PM 2.5 in my neighborhood before taking my baby daughter outside or going for a run in the park. Many others will be doing the same. At least this Thursday morning, there was a strong wind in Beijing, and the sky was blue, and Harbin felt far away.