Why is photochemical smog called LA smog?

Why is photochemical smog called LA smog?

Photochemical smog: This type of smog was observed in Los Angeles(1940s) and hence named as Los Angeles smog. It is formed when the air contains NO 2 and hydrocarbons and the mixture is exposed to sunlight. As the reaction take place in the presence of light to form the smog, it is called photochemical smog.

How is photochemical smog formed?

Photochemical smog is produced when sunlight reacts with nitrogen oxides and at least one volatile organic compound (VOC) in the atmosphere. Nitrogen oxides come from car exhaust, coal power plants, and factory emissions. VOCs are released from gasoline, paints, and many cleaning solvents.

What is photochemical smog and its effects?

Photochemical smog is formed when sunlight interacts with certain chemicals in the atmosphere. Ozone is the main component in this type of air pollution. Ozone in the stratosphere protects us against harmful ultraviolet radiation, but on the ground, it is hazardous to human health.

What is the main component of photochemical smog?

The major undesirable components of photochemical smog are nitrogen dioxide (NO2), ozone (O3), PAN (peroxyacetylnitrate), and chemical compounds that contain the –CHO group (aldehydes). PAN and aldehydes can cause eye irritation and plant damage if their concentrations are sufficiently high.

What is the difference between the two types of smog?

Smog formation and entrapment over Los Angeles. Smog, community-wide polluted air. Sulfurous smog, which is also called “London smog,” results from a high concentration of sulfur oxides in the air and is caused by the use of sulfur-bearing fossil fuels, particularly coal. …

Why is smog bad for the environment?

Environmental Impacts Smog affects much more than just human lives; it also has a large impact on the surrounding physical environment. Ozone and PM in particular cause damaging effects: Ozone can damage plant cells and inhibit their growth, reducing the amount of carbon dioxide that they take in during photosynthesis.

How are plants affected by smog?

Air pollutants have a negative impact on plant growth, primarily through interfering with resource accumulation. Once leaves are in close contact with the atmosphere, many air pollutants, such as O3 and NOx, affect the metabolic function of the leaves and interfere with net carbon fixation by the plant canopy.

What are the two components of smog?

Smog, formed mainly above urban centres, is composed mainly of tropospheric ozone (O3); primary particulate matter such as pollen and dust; and secondary particulate matter such as sulphur oxides, volatile organic compounds, nitrogen oxides (NOx) and ammonia gas.

What are smog types?

At least two distinct types of smog are recognized: sulfurous smog and photochemical smog. Sulfurous smog, which is also called “London smog,” results from a high concentration of sulfur oxides in the air and is caused by the use of sulfur-bearing fossil fuels, particularly coal.

When does photochemical smog occur in the air?

What is photochemical smog? Photochemical smog is a mixture of pollutants that are formed when nitrogen oxides and volatile organic compounds (VOCs) react to sunlight, creating a brown haze above cities. It tends to occur more often in summer, because that is when we have the most sunlight. Primary pollutants

Where can you find photochemical smog in California?

Photochemical smog can be severe in the Los Angeles basin of the California coast (see Fig. 17.7 ). Commuting in Los Angeles requires many cars, which produce high emissions of NO x and hydrocarbons.

Where does most of the smog in the world come from?

Today, most of the smog we see is photochemical smog. Photochemical smog is produced when sunlight reacts with nitrogen oxides and at least one volatile organic compound (VOC) in the atmosphere. Nitrogen oxides come from car exhaust, coal power plants, and factory emissions.

What are the primary and secondary pollutants of smog?

These primary pollutants include nitrogen oxides, particularly nitric oxide (NO) and nitrogen dioxide (NO 2 ), and volatile organic compounds. The relevant secondary pollutants include peroxylacyl nitrates (PAN), tropospheric ozone, and aldehydes. An important secondary pollutant for photochemical smog is ozone,…