While New Delhi and other Indian cities choke amid worsening air conditions and half-hearted government measures, neighbouring China -- the world's largest polluter -- is slowly winning its war against pollution.
Over a dozen Indian cities today are where their Chinese counterparts used to be some five years ago.
Until 2009, 16 of the world's 20 most polluted cities were in China. This year, the first 14, including New Delhi, are in India, and only the last four -- minus Beijing -- are in China.
China is notorious for pollution and it's not just an offshoot of four decades of furious industrialisation. The problem stretches back centuries when dynastic leaders ignored the environmental costs of development.
China had no environmental institution until 1972, six years after which the country went into an almost four-decade-long economic frenzy that saw smoke-billowing factories sprout across its landscape.
The government woke up to the problem only in late 2013 when a severe smog descended on Beijing -- dubbed "airpocalypse" -- and an eight-year-old girl in Jiangsu province was diagnosed with lung cancer attributed to air pollution, making her the youngest cancer patient in the country.
This triggered a huge public outcry and, surprisingly, the state-owned media joined the chorus.
"That was a watershed moment. People were angry. It was then that the government decided to monitor PM (particulate matter) 2.5 in 74 cities and make the data public," Ma Jun, Director at the Institute of Public Environmental Affairs, a Chinese NGO, told IANS.
The stability-obsessed Chinese government also realised that merely disseminating data was not enough and announced an ambitious plan to wage a "war on pollution".
Green activists say although China has a long way to go to curb pollution, its efforts have begun to pay off.
The Chinese Environment Ministry said in September that over half of some 650 cities saw air quality improve year-on-year. Now the skies over Beijing are blue -- and on some days exceptionally clean.
"Political will and ambitious targets set by the government in 2013 have delivered very impressive gains, but the level of determination going forward needs to be reaffirmed," Lauri Myllyvirta, senior global campaigner, coal and air pollution, Greenpeace, told IANS.
"Of course, things could still change this year if the first month or two of the winter period show negative progress," he added.
China is the world's largest coal producer and burns half of it itself, causing severe air pollution. But over the years, China has shut many coal-fired power plants and shifted to natural gas heating. This leaves many homes outside Beijing and other provinces extremely cold in winter but reduces smog.
In a bolder decision this October, the Chinese government said it will switch another 1.18 million residential households in the country to natural gas heating this winter.
"If you look at Beijing, the capital's coal consumption has dropped from 22 million tonnes in 2012 to five million tonnes this year," said Ma. "Beijing's 2.5 PM has dropped from 90 to 58 in 2018."
The Chinese standard for PM 2.5 is 35.
China has also cracked down heavily on polluting factories, shutting tens of thousands of them. It has a "green police" which has the power to send its inspection teams to any part of the country, a privilege enjoyed only by the Central Commission for Discipline Inspection.
In 2017, 18,000 companies for were punished for pollution and fines worth $125 million were levied.
The green police also has the power to sack officials for being lax in controlling pollution. Last year, 12,000 officials were disciplined.
Setting off crackers is completely banned in 444 cities, including Beijing.
The glut of cars in Beijing is responsible for 30 percent of the city's air pollution. And to tackle this, the government has placed a limit on license plates of cars. Car rationing is implemented with ease when pollution shoots up.
In another major decision last month, the Chinese market regulator decided to set up a system to recall vehicles that violate the country's pollution and emissions standards. Besides, China has the most number of electric vehicles in the world and it subsidises their manufacture.
The country is, in fact, spending heavily on clean energy -- more than twice the amount invested by the US.
"More actions are needed. The coal consumption has stagnated but we need to reduce it further," Ma said.
"There are many cities in China's coal-belly, Shanxi, which still cannot meet the modest air quality standards. Things have improved, but we have a long way to go."
The World Health Organisation has acknowledged China's efforts in curbing pollution and reckons that India can take a cue from it.