Unit 7 Air Pollution

Air pollution

Refers to harmful substances in the air affecting human health and the environment.

Primary pollutants

Substances emitted directly from sources like burning coal and fossil fuels.

What do coal and fossil fuels release when they are burned

carbon dioxide, sulfur dioxide, nitrogen oxide, and particulate matter

Examples of primary pollutants

Carbon monoxide, nitrogen oxides, sulfur dioxide, ammonia, VOCs

What health issues can primary pollutants cause

cardiovascular disease and respiratory problems

Secondary pollutants

Formed when primary pollutants interact with other substances in the air.

Examples of Secondary pollutants

sulfur trioxide, sulfuric acid, nitric acid, O3, and ammonia

What do secondary pollutants cause?

formation of particulate matter and acid rain

Photochemical smog

Formed by the reaction of nitrogen oxides and volatile organic compounds with tropospheric ozone (03).

Economic / social impact of Photochemical smog

reduces crop yields for farmers —> less profit

Where is Photochemical smog most commonly found

Hot and dry urban areas

What season is photochemical smog more intense

summer because temperatures are higher and there is more sunlight

What are the effects of Photochemical smog

adverse health affects (respiratory damage) and plant / crop damage

Ways to reduce Photochemical smog

reducing vehicle emissions, increase in renewable energy usage

Thermal inversion

Meteorological phenomenon trapping pollutants near the earth's surface due to warm air above cooler air —> creates a temperature reversal in the atmospheric temperature gradient

What causes Thermal inversion

• movement of cold and warm air masses

• presence of high pressure systems

• tropospheric features that trap warm air

When is it most common for thermal inversion to happen

In the winter

Effects of thermal inversion

• trap pollutants near the earth’s surface —> leads to poor air quality and reduced visibility

• prevents clouds from forming —> clear skies with increased solar radiation

What regions are susceptible to thermal inversion

cities situated in valleys or surrounded by mountains

CO2

CO2 is a greenhouse gas released through human activities that traps heat from the sun, increasing the temperature of the Earth

Particulate Matter

tiny particles suspended in the air from natural and human-made sources

Problems with PM

Have serious health affects, especially for those with respiratory and cardiovascular conditions

How does CO2 relate to PM

CO2 emissions from burning fossil fuels can release PM into the air, contributing to air pollution and health problems

What can happen if CO2 levels get to be too high

 lead to an increase in the frequency and severity of wildfires and dust storms, which can release large amounts of PM into the air.

Natural sources of PM

volcanic eruptions, wildfires, dust storms, sea spray, biological processes, natural radioactivity, lightning strikes, forest fires, plants, and volcanoes.

Natural sources of VOCs

Plants (pine trees)

Natural sources of CO2

Aerobic decomposition, Anaerobic decomposition, all living organisms

Indoor air pollutants

Come from sources like tobacco smoke, building materials, and household products.

Carbon Monoxide

a colorless, odorless gas produced by incomplete combustion, such as from a car or fireplace, and can cause asphyxiation

Radon-222

radioactive gas found in the Earth's crust and can cause certain cancers if inhaled or ingested.

How to remove Radon-222 from your house

Proper ventilation

What household products contain VOCs

formaldehyde in upholstery, furniture, and carpets

Asbestos

commonly used in ceilings and insulation, can cause lung cancer if its small fibers are inhaled

Sick Building Syndrome

occur when indoor pollutants are trapped due to lack of ventilation and can cause illness, such as from the buildup of ozone from copier machines

Reduction of Air Pollutants

Achieved through regulations, conservation, and methods like vapor recovery nozzles and catalytic converters.

What was the goal of the Kyoto Protocol and the Paris Agreement

aimed at reducing greenhouse gas emissions and mitigating climate change

Technology to reduce VOCs

Vapor Recovery Nozzles and catalytic converters are installed in vehicles to reduce the release of VOCs and toxic gasses into the air

Ways to remove pollutants from industrial factories

wet and dry scrubbers and electrostatic precipitators are used to remove pollutants from building exhausts and coal-burning power plants

Laws that have been implemented to address air pollution on a national and international level

Clean Air Act, Montreal Protocol, Thematic Strategy on Air Pollution, and Beijing Action Plan

Acid Rain

Occurs when NOX and sulfur dioxides react with water, affecting living and non-living things and can be mitigated by reducing emissions.

Effects of Acid Rain

affects both living and non-living things, damaging plant leaves, lowering soil pH, harming aquatic life, and dissolving rocks and statues

How to reduce Acid rain

educing emissions of SO2 and NOx, increasing efficiency of fossil fuel use, promoting renewable energy sources, planting vegetation, and using pollution control technologies like scrubbers