Where is smog a problem

The improvements to air quality that result from the North American ECA are expected to have large benefits to public health. By the ECA will prevent up to 14, premature deaths annually and reduce respiratory symptoms for nearly five million people each year in the U.

The Ports Initiative is working to develop and implement environmentally sustainable port strategies through partnerships between EPA and ports.

The program identifies opportunities to reduce air pollution and improve air quality in port communities, and reduce the carbon pollution that contributes to climate change while supporting jobs and the economy. EPA is supporting these efforts through a number of programs, including funding through the Diesel Emission Reductions Act.

EPA standards for transportation sources and voluntary programs have resulted in significant reductions in mobile source air toxic emissions. Mobile source hazardous air pollutants have been cut in half since With additional fleet turnover, EPA expects that emission to be cut by 80 percent by the year To achieve the benefits of our regulations, EPA must ensure that the standards set for vehicles, engines and fuels are being met. One way EPA achieves this is by surveillance testing of cars, trucks and engines at our state-of-the-art National Vehicle and Fuel Emissions Laboratory.

The laboratory also provides critical resource to accomplish the vehicle and engine testing work necessary to set vehicle and engine emissions standards and fuel standards. In states and communities throughout the country, state and local leaders are seeking to balance their air quality, climate, and transportation goals.

EPA provides useful information, tools, and links to resources that identify emission reduction strategies, national policies, regulations, incentive-based programs, funding sources, calculators, and other types of assistance to help states and local areas achieve their air quality and transportation objectives.

Skip to main content. Whereas photochemical smog is a more modern phenomena commonly produced by vehicle emissions in contact with sunlight —mostly from burning gasoline and diesel. Visit the page here to learn more about photochemical smog. This page does not include the chemical formulas in the formation of smog—to see them, along with more detail about smog, visit the UC Davis ChemWiki.

Smog forms when pollutants are released into the air. The pollutants are formed both naturally and by humans, however, the human-induced pollutants are of most concern due to the magnitude of pollutants produced by the burning and extraction of fossil fuels , which are known to cause extreme health effects.

The location of smog formation is also of great concern, especially for human health, as a good portion of it is produced within cities where large portions of the population live. One of the primary constituents, ozone, is created through chemical reactions between sunlight and certain pollutants. The other primary constituent, particulate matter, can also form through chemical reactions but is introduced to the atmosphere through other means as well.

Wind may disperse these particles among land, thereby decreasing the amount within a given area. In addition, rainfall may wash these pollutants out of the local atmosphere, [2] however, this can result in other unwanted events like acid rain.

When smog encounters an inversion layer caused by warm areas in the upper atmosphere it can stay over a region for an extended period of time—exposing people to its effects for longer. Visit the inversion layer page to see how this phenomena occurs. The health effects from smog and its components can be severe, and depend on many variables. Smog is harmful when inhaled, with the severity of it depending on the amount inhaled, the types of pollutants contained in it, as well as the individual's age, weight, activity level, and well-being.

Types of effects smog has include: [2]. When sunlight hits these chemicals, they form airborne particles and ground-level ozone —or smog. Ozone can be helpful or harmful. But when ozone is close to the ground, it is bad for human health.

Ozone can damage lung tissue , and it is especially dangerous to people with respiratory illness es like asthma. Ozone can also cause itchy, burning eyes. Smog is unhealthy to humans and animals, and it can kill plants. Smog is also ugly. It makes the sky brown or gray. Smog is common in big cities with a lot of industry and traffic. Cities located in basin s surrounded by mountains may have smog problems because the smog is trapped in the valley and cannot be carried away by wind.

Los Angeles, California, and Mexico City , Mexico, both have high smog levels partly because of this kind of landscape.

Many countries, including the United States, have created laws to reduce smog. Some laws include restriction s on what chemicals a factory can release into the atmosphere, or when the factory can release them.

Some communities have "burn days" when residents can burn waste such as leaves in their yard. These limits on chemicals released into the air reduce the amount of smog. Smog is still a problem in many places. Everyone can do their part to reduce smog by changing a few behaviors, such as:. Today, however, Mexico City is one of the smoggiest places on Earth. More than 4, people died from respiratory ailments as a result. The smog was so thick that the city had to shut down roads, railways, and the airport.

Robbers used the cover of smog to break into houses and shops. Ultraviolet is often shortened to UV. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.

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