The sky is no longer the limit for China's air pollution. Experts say it is spiraling out of control, despite government measures.
Victoria Peak in Hong Kong has drawn tourists to its grand view of the bustling port-city almost 400 meters below for many years.
On a good day, approaching ships are clear from more than 30 kilometers away.
But these days the smog cloaking Hong Kong is so thick that skyscrapers at the base of Victoria Peak are barely visible. Each breath of the coal and carbon dust and sulfur dioxide mix burns the lungs.
Some of the worst air pollution this city has ever experienced is streaming over the border from mainland China.
Edu Hassing, an energy specialist at the Asia Development Bank, says the blackened skies are the unfortunate by-product of China's booming economy.
"Because of the recent economic development, the use of coal has risen dramatically," he says. "Coal is really [the] dominant source of energy in a lot of sectors."
China's industrial furnaces and boilers consume most of the coal and produce most of the air pollution.
Each year, their smoke stacks pour out more than 21 million tons of sulfur dioxide, as gas that causes health problems and damages crops.
And the pollution respects no borders, traveling over Hong Kong, South Korea, and Japan. Traces of coal particles from China have even been found as far away as southern California.
The United Nations has shown that each year this pollution costs China at least $5.3 billion dollars in health care, and with sick workers staying home, countless more dollars in lost productivity.
Chinese authorities say they are dealing with the problem but, for experts, it is far from enough.
For years, China insisted coal use was dropping, but recent government figures show it actually rising, an average 10 percent over the past three years.
And, says Sergio Miranda-da-Cruz, director of the U.N.'s Industrial Development Organization in Beijing, coal use will keep rising.
"The Chinese government intends by 2020 to double their consumption, to three billion tons of coal," he notes.
Scientists say China's coal-burning factories are old and do not use new, cleaner technologies that are available elsewhere.
But Greg Priddy, an energy consultant for the U.S. government, says Beijing is reluctant to enforce clean-up measures that may slow the economy.
"The real problem is that they can't really retire facilities that are obsolete because of the current energy shortage," he explains.
Instead, Mr. Priddy says, Beijing has been seeking alternatives that encourage change, but will not cut energy production or force factories to close.
Major cities in China have implemented new "blue skies" environmental targets. Their goal is for residents to be able to see the sky, not smog, more each year. It looks like Beijing's goal of 227 clear days in 2004 will go down to the wire.
City governments also have put new limits on car emissions, and begun a sulfur-dioxide trading program that sets new emissions standards and deadlines. More-polluted cities can buy credits from those cities that are ahead of schedule in meeting emission standards.
Beijing's attempts to clear the air have received international support and acclaim. But many cities and industries have been reluctant to follow the new regulations.
The U.N.'s Mr. Miranda-da-Cruz says China's environmental authority is doing its best, but is struggling.
"They have promulgated a series of laws which are very well-formulated," he says. "On the other hand, law enforcement in China is not that easy, because of limitations in resources, particularly human resources."
Government officials concede they are fighting an uphill battle. For every new policy they introduce, a hundred new factories spring up, and a thousand new cars hit the roads. Reforms simply cannot keep up with China's roaring economy.