Smog over Hong Kong

Smog over Hong Kong (Photograph by Sailen Barik, National Geographic Your Shot)



n rapidly growing cities such as Beijing and New Delhi, air pollution has become so severe that respiratory disease is on the rise, flights have been grounded, and the public is often warned against letting children play outside.

Chokingly thick blankets of smog are often a byproduct of economic growth, which results in more vehicles on the road and more burning of fossil fuels, especially coal. The bad air can be deadly: Outdoor air pollution, both in cities and rural areas, prematurely killed 3.7 million people worldwide in 2012, according to the World Health Organization. With two-thirds of the population expected to live in cities by 2050, the need to ease urban pollution is particularly acute.

The problem goes beyond respiratory health and quality of life: A recent study published in the Proceedings of the National Academy of Sciences found that in India, short-lived air pollutants such as ozone and black carbon, along with the changing climate, cut 2010 crop yields in half.

Los Angeles offers an example of what cities can do to reduce pollution. Long notorious for its smog, the car-centric city has seen some air pollutants decline by 98 percent over the past 50 years, even though an increasing population has used more gasoline. Rules to make cars and fuels cleaner helped achieve the reductions, but the city still struggles with air quality issues. In 2014, Los Angeles saw an uptick in smog due to heat and drought, suggesting the fight against air pollution remains a challenge for cities dealing with both climate change and population growth.

In the drive to build smarter cities around the world, what is the most important thing we should do to tackle air pollution?

Give your rating for the answers below and share your thoughts in the comments.

  • OPTION 1

    Reduce tailpipe emissions from vehicles.

    Regulations aimed at transportation-related emissions, including fuel standards, idling restrictions for trucks, and manufacturing requirements for vehicles have helped California cut air pollution despite increases in road travel.

  • OPTION 2

    Speed the transition away from coal.

    The burning of coal, a key contributor to air pollution, accounts for about 70 percent of energy consumed in China and about 44 percent in India, according to the U.S. Energy Information Administration. Clean energy advocates are pushing for a transition to solar and wind, but for now, but the reliability and low price of coal power have made it difficult for many countries—including the United States—to abandon.

  • OPTION 3

    Place stronger rules on industry.

    Factories and shipping ports—key sources of dirty air—are going unchecked in many developing regions. In China, the desire to clean up its air for the 2014 Asia-Pacific Economic Cooperation summit led to a temporary shutdown of thousands of factories, along with bans on driving. Powering factories, and shipping the goods they make, causes air pollution. But the problem could be mitigated with rules aimed at making operations cleaner and more efficient. (See related story: "How Much Is the U.S. to Blame for Made-in-China Pollution?")

  • OPTION 4

    Push for binding international targets.

    In a surprise pact with the United States announced in November 2014, China agreed to halt the growth of its emissions by 2030, while the U.S. pledged to cut emissions 26 to 28 percent below 2005 levels by 2025. The agreement, though voluntary, is seen as a signal for other developing nations to make similar commitments. Whether such pledges will be enough—and whether they will actually lower emissions—could help determine the world's progress in curbing emissions that stoke air pollution. (See related story: "3 Obstacles Ahead for U.S.-China Climate Deal")

DrAvnesh Sharma
DrAvnesh Sharma

I am TOTALLY in favor of  mass TRANSPORT  SYSTEM and that to exclusively RAILWAYS, As it is the only system we can modify and use less space rather conserve space if needed (by putting every thing on pillers) as in Delhi Metro. Lot transit money can be saved and  less energy  utilisation if my ideas given a chance.

Jeff Schimpff
Jeff Schimpff

Electric rail transit, powered by clean, renewable energy, would help a lot. Adding more and better bicycle infrastructure has helped increase the numbers and percentages of people who commute to work by bike, and who travel on errands by bike. Even in a cold and snowy climate where I live, shoveling residential sidewalks (where it IS legal and safe to ride) and plowing bike paths makes it easy for me at age 65 to commute by bicycle EVERY WORKDAY OF THE YEAR. Many more people can get off their butts and do the same - or at least participate in carpools with neighbors and co-workers.

Recognizing commuter parking as largely a negative land use rather than a positive use, we need to tax private commuter parking at a rate higher than general property taxes and apply the revenue to efficient, safe public transit.

Afin Azmi
Afin Azmi

I think we have to push productions of car and motorcycle, cause alot emission out of them, I mean here invite u to prefer provide the general transportation, so that emission loss can decrease

Alok Jhaldiyal
Alok Jhaldiyal

In developing countries like India huge population moves to bigger cities due to availability of better opportunities. This has led to increased population and hence increased pollution. One way to provide better living conditions in these urban center is plan the city such that it remains properly ventilated. This is not a permanent cure but will reduce respiratory disease and other pollution related unhealthiness. A properly ventilated cities enables wind flow inside the urban area, that helps in dispersion of pollutants out of it and it also helps in countering the effect of urban heat island.

Ste Schlappi
Ste Schlappi

The US will cut emissions by up to 28% by 2025. China will stop its buildup of pollution by 2030. Damn those Americans; when will they do something toward helping the problem???

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