Study Guide: Agriculture, Air Pollution, Climate Change, Fossil Fuels

Under-nutrition

Lack of sufficient calories.

Over-nutrition

Excess calorie intake leading to obesity.

Malnutrition

Poor nutrient balance.

Food security

Access to sufficient, safe, and nutritious food.

Food insecurity

Limited access due to poverty.

Subsistence agriculture

Small-scale, for family consumption.

Nomadic herding

Seasonal movement of livestock.

Industrial agriculture

Large-scale, mechanized farming.

Agroforestry

Integration of trees and crops.

Organic farming

No synthetic chemicals.

Agricultural Revolution

domestication of plants and animals

use of plows and irrigation

crop rotation techniques

use of fertilizers

mechanization of farming

development of high-yield crops.

Green Revolution

A period of agricultural advancement (1940s-60s) that used high-yield crop varieties, synthetic fertilizers, and pesticides, increasing food production but leading to environmental issues.

Soil Management Systems

Includes crop rotation, drip irrigation, terracing, contour plowing, cover cropping, conservation tillage, and composting.

Feedlots

Benefits include high meat production and economic efficiency; costs include water contamination, antibiotic resistance, and ethical concerns.

GMOs

Genetically modified organisms for improved yield and resistance, with pros like higher yields and pest resistance, and cons like unknown long-term effects and biodiversity concerns.

Atmosphere Composition

Nitrogen (N2): ~78%, Oxygen (O2): ~21%, Other gases (argon, CO2, etc.): ~1%.

Good ozone

In stratosphere, protects from UV radiation.

Bad ozone

In troposphere, a component of smog.

Climate

Long-term atmospheric conditions.

Weather

Short-term atmospheric changes.

Atmospheric Inversion

A layer of warm air trapping pollutants below.

Sources of Air Pollution

Natural sources include volcanos and wildfires; man-made sources include coal burning and vehicle emissions.

Primary Pollutants

Directly emitted pollutants such as CO and SO2.

Secondary Pollutants

Formed by chemical reactions, examples include ozone and acid rain.

Lead Pollution (1970s)

Major source was leaded gasoline.

Smokestack Scrubbers

Reduce emissions by trapping pollutants.

Smog

Industrial smog is sulfur-based (coal burning); photochemical smog involves NOx & VOCs reacting with sunlight.

Montreal Protocol

Reduced CFCs to protect the ozone layer.

Acid Deposition

Caused by sulfur & nitrogen oxides from fossil fuel combustion, leading to acid rain and soil degradation.

Climate Change

Long-term shifts in temperature, precipitation.

Global Warming

The increase in Earth's average temperature.

Factors Influencing Climate

Solar radiation, Greenhouse gases, Ocean currents.

Greenhouse Effect

Natural: Maintains Earth's temperature. Human-enhanced: Excess GHG emissions.

Greenhouse Gas Warming Potentials

Methane (CH4) > Nitrous Oxide (N2O) > CFCs > CO2.

Keeling Curve

Shows CO2 increase since the 1950s.

CO2 Historical Data

Determined using ice cores (800,000 years). CO2 historically < 300 ppm, now exceeding 400 ppm.

Evidence of Climate Change

Ice loss, sea level rise, glacial retreat, climate refugees.

Impact of Ice Melt

Greenland/Antarctica melt → Sea-level rise.

Ocean Acidification

CO2 dissolves into oceans, affecting corals.

Climate Change & Organisms

Early plant leafing, bird migration shifts.

Climate Change & Society

Health risks, economic shifts, displacement.

Mitigation vs Adaptation

Mitigation: Reduce emissions. Adaptation: Adjust to climate effects.

Conventional Fossil Fuels

Coal, Oil, Natural Gas.

Formation of Fossil Fuels

Organic matter buried under heat & pressure for millions of years.

Carboniferous Period

~280-340 million years ago, high biomass burial led to coal deposits.

Dominant Energy Source (2020)

Fossil fuels (Coal, Oil, Gas) still dominate over renewables.

Fracking

Extracts oil & gas from shale rock.

Pros & Cons of Fossil Fuels

Coal: High CO2, mining damage. Oil: Versatile, but spills & CO2. Natural Gas: Cleaner, but methane leaks.

Natural Gas Formula

CH4 (Methane).

Non-Conventional Fossil Fuels

Oil sands, shale gas (fracking).

Coal Mining Methods

Strip mining, subsurface mining, mountaintop removal.

Environmental Impacts of Coal Mining

Acid mine drainage, deforestation.

Reclamation Laws

Surface Mining Control and Reclamation Act (1977).

Why Shift Away from Coal?

Black lung disease, CO2 emissions, transportation costs, oil versatility.

CO2 Emissions by Fuel Type

Coal > Oil > Gas.

Fractional Distillation of Oil

Separates crude oil into usable products (fuel, plastics, etc.).

Hubbert's Peak

Predicts peak oil production and decline.

Marcellus Shale

Large natural gas deposit in the U.S.

Nuclear Energy

Uses Uranium-235. Pros: Low emissions, high energy output. Cons: Waste disposal, radiation risks.

Nuclear Disasters

Chernobyl (Human error), Fukushima (Tsunami).