Energy, Air Pollution, Ozone Depletion & Atmospheric Layers

Energy and Units

Energy is the capacity to do work. The joule is a standard unit of measurement for work and energy. Potential energy is stored energy. Kinetic energy is the energy of motion.

Fossil Fuels and Consumption

Fossil fuels: oil, natural gas, and coal. Fossil fuels provide 90% of many energy systems. Industry is the single largest consumer of commercial energy. Less than 10% of our commercial energy comes from renewable sources.

Nuclear Energy and Waste Storage

Nuclear energy is generated by the fission of enriched uranium. A noted storage site for radioactive waste is Yucca Mountain in Nevada.

Alternative Energy Sources

Alternative energy sources include wind, currently one of the fastest-growing renewable energies. Solar collectors can be passive or active.

Regulatory Actions and Air Pollutants

Regulatory actions: Clean Air Act (1970). (see tab 12.2)

Major Air Pollutants

• Carbon Monoxide (CO) — colorless, odorless; sources include cigarette smoke and incomplete combustion. CO reacts with hemoglobin in red blood cells, reducing oxygen transport.
• Nitrogen Dioxide (NO2) — reddish-brown gas from fossil fuel burning in motor vehicles; causes lung irritation and damage.
• Sulfur Dioxide (SO2) — colorless gas from coal burning in power plants; can cause breathing problems in healthy people.
• Suspended Particulate Matter (SPM) — a variety of particles and droplets; from burning coal in power and industrial plants.
• Ozone (O3) — a highly reactive, irritating gas with an unpleasant odor that forms in the troposphere by chemical reactions with volatile organic compounds; causes breathing problems. Bad ozone occurs in the troposphere; good ozone is in the stratosphere.
• Lead — a solid toxic metal and its compounds emitted into the atmosphere as particulate matter; accumulates in the body and brain, can cause nervous system damage and developmental delays, and can harm wildlife.

International Protocols

Montreal Protocol — reduces chlorofluorocarbons (CFCs) that destroy O₃ in the stratosphere.

Primary and Secondary Pollutants

Primary: NOx and SOx. Secondary: nitric and sulfuric acids formed in the atmosphere.

Global Warming and Greenhouse Gases

Global warming: understand the relationship between greenhouse gases (primarily CO₂) and climate change.

ESSAY: Air pollution affects the Earth's atmosphere and climate in several ways. 3

Greenhouse Gases (GHGs):

• Methane
• Nitrous oxide
• Carbon dioxide (primarily from fossil fuel burning, agriculture, and deforestation)

Mitigation: use renewable energy and cleaner practices to reduce emissions.

Ozone Depletion and Acid Deposition

Ozone Depletion: CFCs and halons (used in refrigerants and aerosols) destroy stratospheric ozone; the Montreal Protocol addresses these substances.

Acid Deposition (acid rain, acid snow): sources include volcanoes and wildfires; reduce emissions by using cleaner energy sources — renewable energy, natural gas, and by reducing fossil fuel use — to limit acid deposition.

Atmospheric Layers

• Troposphere: the lowest layer of the atmosphere.
• Stratosphere: contains the ozone layer.
• Mesosphere: the layer above the stratosphere.
• Thermosphere: a high-altitude layer of the atmosphere.