ESCI 1 Lecture Notes - Lecture 7: Tropospheric Ozone, Ozone Layer, Passive Smoking
Air Quality
Air Quality and
Air Pollution
● Air quality
○ Gases and small particles in atmosphere that influence
ecosystems or human well-being
● Air pollution
○ Gases and particles present in high enough concentrations to
harm humans, organisms, and structures
● Gases of atmosphere
○ Nitrogen (N2), oxygen (O2), argon (Ar) is over 99% of the
atmosphere
● Trace gases are present in concentrations of parts per million
○ Some are stable while others vary widely in place and time
● Volatile Organic Compounds (VOCs)
○ Chemicals that vaporize into the air
○ Either natural or anthropogenic
● Aerosols
○ Tiny solid and liquid particles suspended in the air like
clouds and fog
● Primary air pollutants
○ Chemicals and particles directly released into the air
● Secondary air pollutants
○ Chemicals and particles that are formed by reaction of other
chemicals or aerosols in the atmosphere
■ Ozone (O3): ground level is dangerous while
atmospheric ozone protects us from the sun
Photochemicals
● Secondary pollutants facilitated by sunlight
○ Causes the sunniest cities are also some of the most polluted
● Ground level ozone: vehicle emissions containing nitrogen oxides
and VOCs interact in the presence of sunlight
○ From paints, solvents, and fuel evaporation
Point/Nonpoint Sources
● Point sources
○ Stationary, localized sources like smoke stacks or factoriest
● Non-Point Sources
○ Numerous sources that produce a relatively small amount
like cars or residential fireplaces
Indoor Air
Pollution
● Generally more polluted than outside air
○ Cleaning products and domestic chemicals (pesticides, bug
spray, beauty products)
● Combustion by-products
○ Carbon monoxide, nitrogen, and sulfur oxides, VOCS,
Document Summary
Gases and small particles in atmosphere that influence. Gases and particles present in high enough concentrations to harm humans, organisms, and structures. Nitrogen (n2), oxygen (o2), argon (ar) is over 99% of the. Trace gases are present in concentrations of parts per million. Some are stable while others vary widely in place and time. Tiny solid and liquid particles suspended in the air like clouds and fog. Chemicals and particles directly released into the air. Chemicals and particles that are formed by reaction of other chemicals or aerosols in the atmosphere. Ozone (o3): ground level is dangerous while atmospheric ozone protects us from the sun. Causes the sunniest cities are also some of the most polluted. Ground level ozone: vehicle emissions containing nitrogen oxides and vocs interact in the presence of sunlight. Stationary, localized sources like smoke stacks or factoriest. Numerous sources that produce a relatively small amount like cars or residential fireplaces.