But especially for the people of Beijing -- and Delhi and Tehran, among other cities currently choking on dirty emissions -- that final goodbye can't come soon enough.
The images are hard to miss and harder to ignore: women, men, children and even pets enveloped in an almost tangible haze, forced to wear face masks as they go about their daily lives -- bicycling, shopping, getting married.
The statistics are equally alarming: More than 4,000 Chinese die daily from air pollution. And that figure may even be an underestimate, as pollution levels have risen since researchers crunched those numbers earlier this year.
A tragedy is indeed unfolding, and threatening to escalate.
On multiple days this December, the air in Beijing measured at least 20 times dirtier than what the World Health Organization deems safe to breathe.
The concentration of PM2.5 -- the tiny air particles that pose the greatest health risks – reportedly reached 647 micrograms per cubic meter near Tiananmen Square on Christmas morning.
This Tuesday, parts of Beijing again registered counts above 500. The WHO sets their limit of exposure at no more than 25 micrograms per cubic meter over a 24-hour period.
Experts warn that the situation will likely worsen in the weeks ahead.
"We're just getting into high season," said John Groopman, an environmental health expert at Johns Hopkins Bloomberg School of Public Health, as he prepped for a trip to China this week to research the issue.
Cold weather, he explained, can trap polluted air near the surface of the earth.
Meanwhile, more pollution is generally created during winter months due to increased heating, which is mostly supplied in China by burning coal.
The poster child for air pollution troubles, China also offers a cautionary tale for other parts of the world.
Pollution is currently soaring in parts of Iran and Italy, for example, where schools, vehicles, football matches and even pizza ovens have shut down in efforts to clean up the toxic air.
Groopman suggests tha India, whose rapidly growing population is even more dependent on coal than China, may be in the worst shape of all.
A study released in February found that 660 million Indians lose an average of 3.2 years of life due to air pollution exposure.
Bad air from Asia can also travel overseas, contributing to the mercury and other pollution plaguing the U.S. West Coast.
Overall, according to the WHO, bad air causes the premature deaths of more than 7 million people every year.
And the list of air pollution's effects is well-known and staggering: heart disease, lung disease, cognitive problems, obesity and even increased crime rates.
"It's really quite obvious that no one should be breathing this," said Groopman.