Environmental Issues Exam 3

Green Revolution

A period of increased agricultural production due to high-yield crops, synthetic fertilizers, and advanced irrigation.

Primary causes of the global food crisis

Climate change, conflict, population growth, unequal food distribution, and reliance on industrial agriculture.

GMOs (Genetically Modified Organisms)

Crops modified for higher yield, pest resistance, or environmental tolerance.

Integrated Pest Management (IPM)

A sustainable pest control strategy combining biological, cultural, and chemical practices.

Impact of high-input agriculture

Increased yields but also soil degradation, water pollution, and high fossil fuel use.

Pesticides and Rachel Carson

Carson's "Silent Spring" exposed dangers of DDT, sparking the environmental movement.

Factors that influence water renewal and contamination

Precipitation, filtration, land use, pollution sources, and water infrastructure.

Desalination

Removing salt from seawater; expensive and energy-intensive, with environmental concerns.

Bottled water and microplastics

Bottled water can contain tiny plastic particles that contribute to pollution and may affect health.

Point source pollution

Pollution from a single, identifiable source, like a pipe or factory discharge.

Non-point source pollution

Diffuse pollution from multiple sources, like runoff from agriculture or urban areas.

Love Canal

Famous toxic waste site in NY that led to public health crises and Superfund legislation.

Three Mile Island (TMI)

A partial nuclear meltdown in Pennsylvania in 1979 that raised safety concerns.

Valley of the Drums

A major hazardous waste site in Kentucky, highlighting poor industrial waste practices.

Cultural eutrophication

Nutrient enrichment in water bodies causing algal blooms and oxygen depletion.

Riparian buffers

Vegetated areas along waterways that filter runoff and reduce water pollution.

Superfund (CERCLA)

A U.S. law to clean up hazardous waste sites and make polluters pay for damages.

World/US commercial energy use pie chart

Majority use is fossil fuels (oil, coal, natural gas), with smaller shares from renewables and nuclear.

Why we continue to use fossil fuels

They are energy-dense, affordable, and supported by existing infrastructure.

Net energy

The usable energy left after subtracting the energy used to produce it.

Life expectancy of commercial energy sources

Fossil fuels last decades; renewables are potentially infinite; depends on usage rates.

Environmental impact of commercial energy sources

Fossil fuels pollute; nuclear has waste risks; renewables have low impact but some land use.

Coal: pros

Pros: cheap, abundant.

Coal: cons

Cons: high CO₂, air pollution.

Oil: pros

Pros: high energy density.

Oil: cons

Cons: spills, emissions.

Natural gas: pros

Pros: cleaner than coal.

Natural gas: cons

Cons: methane leaks, fracking concerns.

Nuclear energy: pros

Pros: low emissions.

Nuclear energy: cons

Cons: radioactive waste, high cost.

Solar energy: cons

Cons: intermittent, expensive upfront, weather dependent

Solar energy and Wind energy: pros

Pros: renewable, clean.

Wind energy: cons

Cons: variable output, wildlife concerns.

Renewable energy: disadvantages

Intermittent output, higher upfront costs, land and resource use.

Hydropower: cons

habitat disruption, displacement.

Hydropower: pros

Pros: reliable, renewable.

Hydrologic fracturing (fracking)

Extracting oil/gas using pressurized fluid; can contaminate groundwater and is loosely regulated.

Clean Water Act and fracking

Fracking is exempt from key Clean Water Act provisions (Halliburton Loophole).

PA State Bill 367 (if covered)

State-level legislation—check course notes for specific content covered.

Natural gas boom's effect on coal and oil

Lower demand and prices for coal/oil due to abundant, cheap natural gas.

Renewable energy: advantages

Sustainable, clean, reduces dependence on fossil fuels.