Air Pollution Types and Effects

Air Pollution

• Definition: Air pollution refers to the presence of harmful substances in the air that can cause damage to humans, animals, and the environment.
• Types of pollutants:
  • Primary pollutants: directly emitted from sources (e.g. vehicles, industries)
  • Secondary pollutants: formed in the atmosphere through chemical reactions (e.g. ozone, smog)
• Effects of air pollution:
  • Respiratory problems
  • Cardiovascular diseases
  • Cancer
  • Environmental damage

Wind Patterns

• Global wind patterns:
  • Trade winds: blow from high pressure to low pressure near the equator
  • Westerlies: blow from high pressure to low pressure in mid-latitudes
  • Jet stream: fast-moving winds in the upper atmosphere
• Local wind patterns:
  • Sea breezes: blow from sea to land during the day
  • Land breezes: blow from land to sea at night
  • Mountain and valley breezes: caused by temperature differences

Air Pressure

• Definition: Air pressure is the force exerted by the weight of air in the atmosphere.
• Measurement units: atmospheres (atm), millibars (mbar), pounds per square inch (psi)
• Factors affecting air pressure:
  • Temperature: warm air rises, reducing pressure
  • Humidity: moist air is heavier, increasing pressure
  • Altitude: pressure decreases with increasing altitude
• Effects of air pressure:
  • Weather patterns: high pressure brings fair weather, low pressure brings storms
  • Aviation: air pressure affects aircraft performance

Oxygen Cycle

• Definition: The oxygen cycle is the process by which oxygen is exchanged between the atmosphere, biosphere, and geosphere.
• Steps in the oxygen cycle:
  1. Photosynthesis: plants produce oxygen as a byproduct
  2. Respiration: animals and plants consume oxygen and release carbon dioxide
  3. Decomposition: microorganisms break down organic matter, releasing oxygen
  4. Weathering: oxygen is released from rocks and minerals

Atmospheric Composition

• Gases in the atmosphere:
  • Nitrogen (78.08%): inert, non-reactive
  • Oxygen (20.95%): essential for life
  • Argon (0.93%): noble gas, non-reactive
  • Carbon dioxide (0.04%): greenhouse gas, affects climate
  • Water vapor (variable): influences weather and climate
• Other atmospheric components:
  • Aerosols: particles suspended in the air
  • Ozone: formed in the stratosphere, protects from UV radiation

Air Pollution

• Air pollution is the presence of harmful substances in the air that can cause damage to humans, animals, and the environment.
• There are two types of pollutants: primary pollutants, which are directly emitted from sources such as vehicles and industries, and secondary pollutants, which are formed in the atmosphere through chemical reactions, such as ozone and smog.
• Air pollution can cause respiratory problems, cardiovascular diseases, cancer, and environmental damage.

Wind Patterns

• Global wind patterns include trade winds, which blow from high pressure to low pressure near the equator, westerlies, which blow from high pressure to low pressure in mid-latitudes, and the jet stream, which are fast-moving winds in the upper atmosphere.
• Local wind patterns include sea breezes, which blow from sea to land during the day, land breezes, which blow from land to sea at night, and mountain and valley breezes, which are caused by temperature differences.

Air Pressure

• Air pressure is the force exerted by the weight of air in the atmosphere.
• Air pressure is measured in units such as atmospheres (atm), millibars (mbar), and pounds per square inch (psi).
• Factors that affect air pressure include temperature, humidity, and altitude, with warm air rising and reducing pressure, moist air being heavier and increasing pressure, and pressure decreasing with increasing altitude.
• Air pressure affects weather patterns, with high pressure bringing fair weather and low pressure bringing storms, and also affects aircraft performance.

Oxygen Cycle

• The oxygen cycle is the process by which oxygen is exchanged between the atmosphere, biosphere, and geosphere.
• The oxygen cycle involves four steps: photosynthesis, in which plants produce oxygen as a byproduct, respiration, in which animals and plants consume oxygen and release carbon dioxide, decomposition, in which microorganisms break down organic matter and release oxygen, and weathering, in which oxygen is released from rocks and minerals.

Atmospheric Composition

• The atmosphere is composed of several gases, including nitrogen (78.08%), oxygen (20.95%), argon (0.93%), and carbon dioxide (0.04%), which is a greenhouse gas that affects climate.
• Other atmospheric components include aerosols, which are particles suspended in the air, and ozone, which is formed in the stratosphere and protects from UV radiation.
• Water vapor is also present in the atmosphere, with variable levels, and influences weather and climate.

Composition of Air

• Air is a mixture of gases, comprising 78% nitrogen (N2), 21% oxygen (O2), 0.93% argon (Ar), 0.04% carbon dioxide (CO2), water vapor (H2O) in varying amounts, and trace amounts of other gases like neon (Ne), helium (He), and methane (CH4).

Properties of Air

• Air is an invisible, odorless, and tasteless gas.
• As a mixture, air is not a compound.
• Air has mass and occupies space.
• Air exerts pressure on surfaces it comes into contact with.
• Air expands and contracts in response to changes in temperature and pressure.

Importance of Air

• Air is essential for human and animal respiration.
• Air supports combustion and fire.
• Air plays a crucial role in weather and climate.
• Air is necessary for plant growth and photosynthesis.
• Air affects the environment and ecosystem balance.

Layers of the Atmosphere

Troposphere

• The lowest layer of the atmosphere, extending up to 12 km high.
• This is where weather occurs.

Stratosphere

• The layer between 12-50 km high.
• The ozone layer in this layer protects from UV radiation.

Mesosphere

• The layer between 50-80 km high.
• Meteors burn up in this layer.

Thermosphere

• The layer between 80-600 km high.
• Atmospheric gases interact with solar winds in this layer.

Exosphere

• The outermost layer of the atmosphere.
• Atmospheric gases escape into space from this layer.