Air Quality and Environmental Issues
Why is Clean Air Important?
Humans breath in oxygen to provide energy for their bodies and breath out carbon dioxide, as a waste product. Pollutants can cause complications for gas exchange, introduce foreign bodies which may cause illness, irritation/allergies or asthma. Air pollution can increase risk of death for individuals who suffer from heart disease and puts the very young and very old at greater risk as well.
Your Nose as a Filter
Humans - air is in contact with our eyes and lungs - it passes through our nose and nose hairs, mucus (snot), and cilia (small hairs) help filter out some particulate matter. What ever gets past the mucus and cilia enters our lungs, which are delicate.
Monitoring Air Qualty
WHO: Environmental Protection Agency (EPA) - monitors air quality, as well as other environmental conditions
WHAT: Several types of pollutants are monitored
Airnow.gov
WHAT: Several types of pollutants are monitored
Airnow.gov
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Air Quality Index
Pollutants: substances that contaminate air, water, or soil (we are focusing on air this week)
Ex. CO2, particles, sulfur dioxide, volatile organic compounds (VOCs)
Pollution: the contamination of Earth’s air, water, or soil
SOURCES:
Natural Sources:
Human Activities:
Fossil Fuel: gasoline, oil, coal, natural gas
Effects of Air Pollution
Enhanced Natural Occurrence: The Greenhouse Effect
The greenhouse effect is what allows the sun’s energy to reach the Earth and keeps the troposphere warm. It is a natural phenomenon that is key to life on Earth, as we know it. However, there can be too much of a good thing!
Ex. CO2, particles, sulfur dioxide, volatile organic compounds (VOCs)
Pollution: the contamination of Earth’s air, water, or soil
SOURCES:
Natural Sources:
- Volcanic eruptions
- Forest Fires
- Dust Storms
- Wind borne pollen and mold
Human Activities:
- Burning fossil fuels/Vehicle emissions
- Farming and Construction
- Household Products: paint thinners, air fresheners, etc.
Fossil Fuel: gasoline, oil, coal, natural gas
Effects of Air Pollution
Enhanced Natural Occurrence: The Greenhouse Effect
The greenhouse effect is what allows the sun’s energy to reach the Earth and keeps the troposphere warm. It is a natural phenomenon that is key to life on Earth, as we know it. However, there can be too much of a good thing!
- Green House Effect
- Primary Source: Burning Fossil Fuels
- Effect:
- Increased amount of solar radiation is able to reach Earth’s surface (CO2 and H2O act as windows, letting sunlight in)
- Increased amount of heat trapped near Earth’s surface
- Potential to contribute to global climate change
- Timing: Year Round
- Health Impacts: none health specific, changes in Earth’s climate may be severe
- Flooding, changes in climate patterns, melting of ice caps/glaciers
Problem: Thinning of Ozone Layer (in Stratosphere)
- What: The ozone layer protects us from UV radiation, but is thinning over the poles
- Primary Source: Chlorofluorocarbons (CFCs) - from spray bottles
- Effect: Increased UV radiation passing through ozone layer
- Timing: Worst in spring over respective poles
- Health Impacts: increased skin cancer and eye damage
Problem: Smog
- What: Smoke (chemicals) + fog (moisture in air) = SMOG (smoke/fog)
- Primary Source: Burning of Fossil Fuels
- Burning Fossil Fuels - combining pollutants with moisture in the air
- Coal is the type of fossil fuel most often associated with London/Industrial Smog
- Gasoline and other types of fossil fuels create Photochemical Smog
- Burning Fossil Fuels - combining pollutants with moisture in the air
- Effect:
- Photochemical Smog: sunlight + pollutants (from fossil fuels) + moisture in air = ozone + other pollutants
- London/Industrial Smog: coal smoke + moisture in air = smokey fog and acid rain
- Timing:
- Photochemical Smog - warm sunny days, low breeze
- London/Industrial Smog - overcast, humid days
- Heath Impacts: breathing complications including asthma, damage to lungs, reduced lung function
Problem: Ground Level Ozone
- What: O3 - provides protection when located in ozone layer of the stratosphere, harmful in the troposphere (ground level)
- Primary Source: Burning Fossil Fuels - largely car exhaust
- Chemicals from Fossil Fuels + Sunlight = O3
- Effect: O3 levels in troposphere increase, negative effects on crops, damages some textiles
- Timing: Hot, sunny, low breeze conditions
- Health Impacts: lung irritation, increase asthma attacks, eye irritation, chest pain, coughing, nausea, headaches, etc.
*Note: Ozone is beneficial in the stratosphere, but not in the troposphere!*
Problem: Acid Rain
- What: Lower pH of rain (or other precipitation) than normal.
- Primary Source: Chemicals from Fossil Fuels
- Chemicals from Fossil Fuels + Moisture = acidic precipitation
- Effect: The acidic water changes the nutrient composition of the soil and any body of water it becomes a part of, harming plants and aquatic animals.
- Timing: year round
- Health Impacts: acid rain is not “dangerous” to humans, nitrogen oxides and sulfur oxides can cause breathing problems