Response to a City's Smog Points to a Change in Chinese Attitude BEIJING - Emergency measures came swiftly in Harbin, the northeastern city blanketed with hazardous smog this week: Schools were shut down, buses ordered off the roads, the airport closed, police roadblocks set up to check tailpipe emissions from cars. City officials even fanned out in the surrounding countryside, ordering farmers to stop burning the cornstalks left in their fields after the harvest. They were reacting to the first notable surge of air pollution in China this autumn. Residents across the nation's north fear that the smog is a sign of things to come. With winter approaching, cities north of the Huai River are turning on their coal-fired municipal heating systems, whose emissions were found in one study to shorten residents" life spans by an average of five years. In Harbin, still, moist air trapped the pollution at ground level, leaving people to walk through a gray miasma wearing face masks. Visibility was so bad that two buses got lost plying their routes. But the emergency measures showed that the government was trying to address the problem rather than merely cover it up, as it might have done in past years, some environmental activists said. Action plans in Harbin, Beijing and other cities, along with broad national policies meant to curb air pollution announced last month, signal that some officials are serious about tackling the chronic problem. On Thursday, the Ministry of Environmental Protection said it was sending inspection teams to cities across China for the winter to ensure that environmental regulations were enforced. Awareness of various kinds of pollution - air, water and soil - has risen quickly this year, especially among middle-class urbanites. Chinese news media, including official state outlets, are reporting more aggressively on the causes and effects of pollution. An editorial in Beijing News on Wednesday took note that last week the World Health Organization had classified air pollution as a leading cause of cancer, and said that on days when the air is hazardous, "containing the pollution and protecting the health of residents is the highest priority." But the advocates say enforcement is often a weak point, even when leaders understand that cleaning up the environment has become critical to maintaining social and political stability. "I give credit to the local government for taking these measures," Ma Jun, an environmental advocate, said of the emergency actions in Harbin. Of course, they will have some problem with their image, the city's image - but on the other hand, it shows they put people's health ahead of saving face. "Having said that, I think it's not enough," he added. I think people won't be satisfied with just knowing which day to put on face masks or not go to school or keep their children indoors. They really want blue-sky days. Under pressure from the public, Beijing in 2012 became the first Chinese city to announce levels of an especially hazardous category of particulate matter, known as PM 2.5, in the air. Since then, 113 other cities have followed suit. The data can be seen online in real time, which was how much of China followed the crisis in Harbin. On Monday and Tuesday, air-quality monitoring stations in some parts of the city reported PM 2.5 concentrations that exceeded 1,000 micrograms per cubic meter - 40 times the level deemed safe by the W.H.O. Since 2007, the Ministry of Environmental Protection has published an annual list of high-polluting industrial plants around China. The latest identifies 4,189 factories that, together, release 65 percent of the China's total industrial air pollutants. "We need to know where they are, what kinds of pollutants they discharge, the volume and whether they are in compliance with discharge standards," Mr. Ma said, adding that local governments gather that data but do not release it. Advocates hope that identifying the polluters publicly will help to shame them into improving, Mr. Ma said, with pressure coming from "whoever invests in the polluting factories, the banks giving them loans, the brands that source from these polluters." The central government is apparently stepping up pressure as well. One goal of the national plan announced last month was to reduce the concentration of PM 2.5 in three heavily populated industrial regions by 15 to 25 percent, compared with 2012 levels. Prime Minister Li Keqiang said last month that the cities of Beijing and Tianjin and the province of Hebei, all in northern China, would cut down their use of coal, the main source of air pollution, by 80 million tons a year in the near future. Still, environmentalists worry that growth-minded local officials and businesses will be reluctant to go along. "Chinese leaders have produced an impressive flurry of policies on air pollution this year, but regulators still suffer from insufficient authority; rapid economic growth means that a steady stream of pollution sources come on line every day; and vested business interests are sure to scream bloody murder every step of the way," Alex L. Wang, a scholar of Chinese environmental policy and a law professor at the University of California, Los Angeles, said in an e-mail. "It's one thing to have a strategy, and another to execute it well," he added. Huang Wei, who works on climate and energy issues at Greenpeace East Asia, said officials needed to focus on bigger solutions, not stopgap measures. "The situation will not change as long as China has an over 70 percent energy dependency on coal," she said. The long-term solution is to get rid of heavy energy-consuming industries. Until that happens, Chinese citizens are bracing for many more days of heavy pollution, and officials are announcing a wider array of emergency measures for the worst days. On Tuesday, the Beijing government adopted a plan for emergencies when the forecast calls for three or more days with pollution rated as serious. A "red alert" would be issued, schools would be shut down and use of private cars would be limited to alternate days, depending on their license plate numbers. Skeptics point out that wealthier households can buy extra vehicles to get around that rule. And Beijing News said in its editorial that on "red alert" days, everyone should stay home, not just children. "Faced with the increasingly serious pollution levels in Beijing," it said, "coupled with the carelessness of residents in protecting themselves against pollution, the emergency plan is still inadequate." Mia Li and Chen Jiehao contributed research.