Science, Matter, Energy, Systems, and Sustainability

Fundamentals of Environmental Science and the Scientific Process

Definition of Science: Science is an interdisciplinary field focused on showing how nature works and using that knowledge to describe what is the likely effects.
Core Assumptions: Scientific inquiry operates on the fact that events in the real world follow cause-and-effect patterns, which can be identified, measured, and understood through observations, measurements, and experimentation.
The Scientific Method Process:
- Identify a Problem: Recognize observation or existing data.
- Literature Search: Finding out what is already known about the problem.
- Formulate a Question: Define the specific aspect to be questioned
- Perform Experiments & Gather Data: Conduct controlled investigations to collect empirical facts.
- Analyze Data: Search for patterns, trends, or mathematical relationships.
- Propose a Scientific Hypothesis: Formulate a testable, tentative explanation for the observed data.
- Make Testable Projections & Test: Design further experiments to test predictions derived from the hypothesis.
- Accept or Revise Hypothesis: Modify the hypothesis if data fails to support projections.

Controlled Experiments and Ecosystem Dynamics: Core Case Study

Hubbard Brook Experimental Forest Study (New Hampshire):
- Researchers: Carried out by botanist F. Herbert Bormann, forest ecologist Gene Likens, and their colleagues.
- Objective: Compare the loss of water and soil nutrients between an undisturbed, uncut forest (control site) and a deforested area (experimental site).
- Experimental Design:
  - Built V-shaped concrete dams across creeks at the bottom of forested valleys to collect, measure, and analyze all surface outflow water and dissolved nutrients.
  - Control Site: Undisturbed mature forest valley where water and soil nutrient retention were measured.
  - Experimental Site: A nearby forested valley was completely deforested (all trees and shrubs cut down and left in place) and sprayed with herbicides for 3 years to prevent vegetation regrowth.
- Key Findings:
  - Without vegetation to absorb and retain water, total water outflow increased by $30\text{--}40\%$ .
  - Surface runoff accelerated, causing severe topsoil erosion.
  - Overall loss of key plant nutrients (such as nitrate ions, $\text{NO}_3^-$ ) was 6 to 8 times greater in the deforested site than in the undisturbed control forest.
  - Calcium loss in runoff showed a sharp increase beginning in 1965–1966, peaked around 1967–1968, and leveled off by 1971–1972.

Scientific Mindset, Peer Review, and Historical Case Studies

Scientific Mindset Requirements:
- Curiosity and Skepticism: Scientists continuously question results and demand verifiable evidence before accepting hypotheses.
- Critical Thinking Steps:
  1. Maintain skepticism toward all read or heard information.
  2. Evaluate evidence using multiple reliable sources.
  3. Identify and isolate personal assumptions, biases, and beliefs to distinguish objective facts from opinions.
- Role of Creativity: Logic alone is insufficient; intuition, imagination, and creative insights are critical to discovering new scientific principles.
Peer Review: A self-correcting process wherein scientists publish experimental methods, raw data, and theoretical reasoning for critique by other experts in the same field before and after publication.
Revisions in Scientific Hypotheses: Easter Island (Rapa Nui):
- Early Hypothesis: Polynesians arrived 2,900 years ago, reached a population of 15,000, overharvested palm trees for move-statue rollers and firewood, leading to soil erosion, famine, civil war, and population collapse.
- Revised Hypothesis (Terry L. Hunt and Carl Lippo, 2001):
  - Radiocarbon dating indicates Polynesians arrived around 800 years ago, with peak populations never exceeding 3,000.
  - Polynesian rats (stowaways or brought for food) multiplied into millions and consumed palm tree seeds, preventing forest regeneration.
  - Civilization collapse occurred due to European exposure to infectious diseases, slave raids, and the introduction of grazing sheep, rather than self-inflicted ecological warfare.

Limitations and Certainty in Scientific Knowledge

Categories of Science:
- Reliable Science: Data, hypotheses, models, theories, and laws widely accepted by expert consensus within the field.
- Tentative Science: Preliminary results lacking extensive peer testing; subject to future validation or disproof.
- Unreliable Science: Hypotheses or data presented as reliable without undergoing peer review, or those discredited after peer review.
Scientific Theories vs. Scientific Laws:
- Scientific Theory: A well-tested, widely accepted explanation of a complex natural phenomenon (e.g., cell theory, atomic theory). Cannot be dismissed as "just a theory."
- Scientific Law (Law of Nature): A well-tested, widely accepted description of what always happens in nature under specific conditions (e.g., Law of Gravity). Laws cannot be broken.
Intrinsic Limitations of Science:
1. Absolute proof is impossible; science establishes high levels of probability or certainty (typically $90\text{--}95\%$ ).
2. Human bias exists, though peer review significantly reduces its prevalence.
3. Natural systems involve vast numbers of interacting variables, requiring high-speed computer mathematical modeling rather than simple single-variable testing.
4. Statistical estimation techniques (sampling) must be used for massive phenomena (e.g., global annual soil erosion rates).

Structure and Properties of Matter

Definition: Matter is anything that has mass and takes up space.
Physical States: Solid, liquid, and gas.
Chemical Forms:
- Elements: Pure substances with unique chemical properties that cannot be broken down into simpler substances by chemical reactions. Organized in the Periodic Table of Elements (118 known elements).
- Compounds: Combinations of two or more different elements held together in fixed proportions (e.g., water, $\text{H}_2\text{O}$ ; sodium chloride, $\text{NaCl}$ ).
Key Chemical Elements & Symbols:
- Arsenic ( $\text{As}$ ), Bromine ( $\text{Br}$ ), Calcium ( $\text{Ca}$ ), Carbon ( $\text{C}$ ), Copper ( $\text{Cu}$ ), Chlorine ( $\text{Cl}$ ), Fluorine ( $\text{F}$ ), Gold ( $\text{Au}$ ), Lead ( $\text{Pb}$ ), Lithium ( $\text{Li}$ ), Mercury ( $\text{Hg}$ ), Nitrogen ( $\text{N}$ ), Phosphorus ( $\text{P}$ ), Sodium ( $\text{Na}$ ), Sulfur ( $\text{S}$ ), Uranium ( $\text{U}$ ).

Atomic Structure, Isotopes, Ions, and pH

Subatomic Structure of Atoms:
- Atomic Theory: All elements are composed of basic units called atoms.
- Protons: Positively charged subatomic particles ( $+$ ) located in the atomic nucleus.
- Neutrons: Electrically neutral subatomic particles located in the atomic nucleus.
- Electrons: Negatively charged subatomic particles ( $-$ ) moving rapidly outside the nucleus; possess negligible mass compared to protons/neutrons.
- Atomic Number: Total number of protons in the nucleus of an atom (e.g., Carbon = 6, Uranium = 92).
- Mass Number: Combined total number of protons and neutrons in the nucleus (e.g., Carbon-12 has 6 protons and 6 neutrons; Uranium-235 has 92 protons and 143 neutrons).
Isotopes: Forms of an element possessing the same atomic number (protons) but different mass numbers due to varying neutron counts. Carbon-12 ( $98.9\%$ of natural carbon), Carbon-13, and Carbon-14 are key isotopes.
Ions and Acidity:
- Ion: An atom or group of atoms with one or more net positive ( $+$ ) or negative ( $-$ ) electrical charges due to electron gain or loss.
- Key Positive Ions: Hydrogen ion ( $\text{H}^+$ ), Sodium ion ( $\text{Na}^+$ ), Calcium ion ( $\text{Ca}^{2+}$ ), Aluminum ion ( $\text{Al}^{3+}$ ), Ammonium ion ( $\text{NH}_4^+$ ).
- Key Negative Ions: Chloride ion ( $\text{Cl}^-$ ), Hydroxide ion ( $\text{OH}^-$ ), Nitrate ion ( $\text{NO}_3^-$ ), Carbonate ion ( $\text{CO}_3^{2-}$ ), Sulfate ion ( $\text{SO}_4^{2-}$ ), Phosphate ion ( $\text{PO}_4^{3-}$ ).
- pH Scale: A logarithmic measure of relative concentration of hydrogen ions ( $\text{H}^+$ ) and hydroxide ions ( $\text{OH}^-$ ) in aqueous solutions.
  - Neutral Solution: $\text{pH} = 7.0$ ( $[\text{H}^+] = [\text{OH}^-]$ , e.g., pure water).
  - Acidic Solution: \text{pH} < 7.0 ([\text{H}^+] > [\text{OH}^-]).
  - Basic Solution: \text{pH} > 7.0 ([\text{OH}^-] > [\text{H}^+]).
  - Logarithmic Scaling: Every single-unit change on the pH scale represents a 10-fold change in $\text{H}^+$ ion concentration. A solution with $\text{pH } 2$ is 10,000 times ( $10^4$ ) more acidic than a solution with $\text{pH } 6$ .
  - pH Reference Values: Gastric fluid ( $1.0\text{--}3.0$ ), Lemon juice/acid rain ( $2.3\text{--}3.0$ ), Black coffee ( $5.0$ ), Urine ( $5.0\text{--}7.0$ ), Milk ( $6.6$ ), Human blood ( $7.3\text{--}7.5$ ), Seawater ( $7.8\text{--}8.3$ ), Household ammonia ( $10.5\text{--}11.9$ ).

Chemical Compounds, Bonding, and Organic Macromolecules

Chemical Compounds & Formulas:
- Ionic Compounds: Formed by electrostatic attraction between oppositely charged ions arranged in a 3D crystalline lattice (e.g., $\text{NaCl}$ ). Dissolve in water into individual ions.
- Covalent Compounds: Formed by uncharged atoms sharing electron pairs via covalent bonds (e.g., $\text{H}_2\text{O}$ , $\text{CH}_4$ ).
- Key Compound Formulas:
  - Sodium chloride ( $\text{NaCl}$ ), Sodium hydroxide ( $\text{NaOH}$ ), Carbon monoxide ( $\text{CO}$ ), Carbon dioxide ( $\text{CO}_2$ ), Nitric oxide ( $\text{NO}$ ), Nitrogen dioxide ( $\text{NO}_2$ ), Nitrous oxide ( $\text{N}_2\text{O}$ ), Nitric acid ( $\text{HNO}_3$ ), Methane ( $\text{CH}_4$ ), Glucose ( $\text{C}_6\text{H}_{12}\text{O}_6$ ), Water ( $\text{H}_2\text{O}$ ), Hydrogen sulfide ( $\text{H}_2\text{S}$ ), Sulfur dioxide ( $\text{SO}_2$ ), Sulfuric acid ( $\text{H}_2\text{SO}_4$ ), Ammonia ( $\text{NH}_3$ ), Calcium carbonate ( $\text{CaCO}_3$ ).
Organic Compounds: Molecules containing at least two carbon atoms combined with other elements (exception: methane, $\text{CH}_4$ ).
- Hydrocarbons: Compounds consisting exclusively of carbon and hydrogen atoms.
- Simple Carbohydrates: Simple sugars like glucose ( $\text{C}_6\text{H}_{12}\text{O}_6$ ).
- Macromolecules / Polymers:
  1. Complex Carbohydrates: Monomer units of simple sugars linked together. Includes starches (plant energy storage) and cellulose (structural component of plant cell walls, most abundant organic compound on Earth).
  2. Proteins: Long chains of amino acid monomers (20 different amino acids utilized by life). Serve as enzymes (catalysts), structural tissues (hair, skin, muscle), hormones, and immune factors.
  3. Nucleic Acids: Polymers made of nucleotide monomers (each containing a phosphate group, a deoxyribose/ribose sugar, and a nitrogenous base: Adenine, Guanine, Cytosine, Thymine). Form DNA and RNA. Double-helix structure maintained by hydrogen bonds. Human DNA unwound stretches 960 million kilometers (600 million miles).
  4. Lipids: Diverse group of hydrophobic organic compounds non-soluble in water. Includes fats, oils, waxes, and steroids.

Biological Organization: Cells, Genes, and Chromosomes

Cell Theory: All living organisms are composed of one or more cells—the fundamental structural and functional units of life.
Genes: Specific functional segments of nuclear DNA containing sequences of nucleotides that code for instructions (genetic information) to synthesize specific proteins.
Chromosomes: Structures inside the cell nucleus consisting of long DNA molecules wrapped around protein molecules, containing thousands of individual genes.

Changes in Matter and the Law of Conservation of Matter

Physical Change: Alters physical properties (state, size, shape) without changing chemical composition (e.g., liquid water freezing to ice, cutting aluminum foil).
Chemical Change (Chemical Reaction): Chemical composition of reactants changes, rearranging constituent atoms into new chemical products.
- Example Equation: Carbon combustion: $\text{C} + \text{O}_2 \rightarrow \text{CO}_2 + \text{Energy}$ .
Law of Conservation of Matter: In any physical or chemical change, no atoms are created or destroyed; atoms are only rearranged into different physical patterns or chemical combinations.
- Balancing Chemical Equations: $\text{H}_2\text{O} \rightarrow \text{H}_2 + \text{O}_2$ is unbalanced ( $2\text{ H}, 1\text{ O} \rightarrow 2\text{ H}, 2\text{ O}$ ). The balanced equation is:

$2\text{H}_2\text{O} \rightarrow 2\text{H}_2 + \text{O}_2$

Energy Forms, Work, and Electromagnetic Spectrum

Work: Executed when an object is moved over a specific distance by a force:

$\text{Work} = \text{Force} \times \text{Distance}$

Energy: The capacity to perform work or transfer heat. Measured in joules ( $\text{J}$ ), kilojoules ( $\text{kJ}$ ), calories ( $\text{cal}$ ), or kilocalories ( $\text{kcal}$ ).
Kinetic Energy: Energy possessed by matter due to its mass and speed/velocity (moving energy).
- Examples: Flowing water, electricity (flowing electrons), moving air masses (wind).
- Electric Power: Rate at which electrical energy is transferred through a conductor, measured in watts ( $\text{W}$ ) or megawatts ( $\text{MW}$ ).
Electromagnetic Radiation: Kinetic energy traveling as electromagnetic waves driven by electric and magnetic field changes.
- Wavelength Relationship: Short wavelengths carry higher energy content; long wavelengths carry lower energy content.
- Spectrum Progression (Short to Long Wavelength): Gamma rays $\rightarrow$ X-rays $\rightarrow$ Ultraviolet (UV) $\rightarrow$ Visible Light (makes up most solar radiation) $\rightarrow$ Infrared radiation $\rightarrow$ Microwaves $\rightarrow$ TV/Radio waves.

Heat Transfer and Energy Classifications

Heat (Thermal Energy): Total kinetic energy of all moving atoms, ions, or molecules within a substance. Heat naturally flows from warmer objects to cooler objects.
Heat Transfer Mechanisms:
1. Radiation: Thermal energy transfer through space via electromagnetic waves (infrared radiation).
2. Conduction: Thermal energy transfer between solid substances in direct physical contact.
3. Convection: Thermal energy transfer within liquids or gases as warm regions rise and cooler regions sink in circulating currents.
Potential Energy: Energy stored in matter due to its position, spatial arrangement, or chemical state.
- Examples: Water stored behind a dam, chemical energy in gasoline/food/coal, nuclear forces inside atomic nuclei.
- Potential energy converts to kinetic energy when water flows through dam channels or when gasoline burns in an engine.
Energy Resource Classification:
- Renewable Energy: Replenished continually by natural processes on human time scales (solar, wind, hydropower, geothermal, biomass).
- Nonrenewable Energy: Exhaustible resources stored in fixed amounts in Earth's crust, unreplenished on human time scales (oil, coal, natural gas, nuclear power).
- Direct Solar Energy: Supplies $99\%$ of thermal energy warming Earth.
- Commercial Energy: Represents the remaining $1\%$ of energy used; $90\%$ globally and in the US is supplied by nonrenewable fossil fuels.

Laws of Thermodynamics and Energy Efficiency

Energy Quality: Measure of an energy source's capacity to do useful work.
- High-Quality Energy: Concentrated energy with high work capacity (e.g., high-temperature heat, concentrated sunlight, high-speed wind, burning fossil fuels).
- Low-Quality Energy: Dispersed energy with minimal work capacity (e.g., low-temperature heat dispersed in atmosphere or ocean).
First Law of Thermodynamics (Law of Conservation of Energy): Whenever energy is converted from one form to another in a physical or chemical change, no energy is created or destroyed.
Second Law of Thermodynamics: Whenever energy is converted from one form to another in a physical or chemical change, the resulting output is lower-quality or less-usable energy (typically low-temperature waste heat dispersed into the environment). High-quality energy cannot be recycled or reused.
Energy Efficiency: The percentage of total energy input that does useful work without being converted into low-quality heat.
- Incandescent Lightbulb System: Only $5\%$ of original coal chemical energy becomes light; $95\%$ is lost as waste heat during generation ( $35\%$ plant efficiency) and transmission. Light-emitting diode (LED) bulbs provide far higher energy efficiency.
- US Energy Waste: Approximately $84\%$ of commercial energy used in the United States is wasted ( $41\%$ unavoidably due to the Second Law of Thermodynamics, and $43\%$ unnecessarily due to inefficient technologies).

Systems, Throughputs, and Feedback Loops

System Components: A system consists of components interacting in a regular manner. Composed of:
- Inputs: Matter, energy, or information entering from the environment.
- Throughputs / Flows: System processes transforming matter/energy internally.
- Outputs: Products, waste, heat, or information exiting into the environment.
Feedback Loops:
- Positive Feedback Loop: Causes a system to change further in the same direction, amplifying initial change (e.g., vegetation removal $\rightarrow$ soil erosion $\rightarrow$ nutrient loss $\rightarrow$ plant death).
- Ecological Tipping Point: Threshold reached when positive feedback drives a system beyond reversible limits, causing severe degradation or collapse.
- Negative (Corrective) Feedback Loop: Causes a system to change in the opposite direction, moving toward stability (e.g., thermostat shutting off furnace when target temperature is reached; body sweating to reduce temperature; aluminum recycling reducing raw mining requirements).

Principles of Sustainability and Natural Capital

Sustainability: The capacity of Earth's natural systems and human cultural systems to survive, flourish, and adapt to changing environmental conditions indefinitely.
Environmental Science Scope: Interdisciplinary study integrating natural sciences (biology, chemistry, geology) and social sciences (economics, politics, ethics) to examine Earth's function, human interactions, and solutions to environmental problems.
Three Scientific Principles of Sustainability:
1. Dependence on Solar Energy: The sun warms the planet and powers photosynthesis, driving plant production of nutrients.
2. Biodiversity: Variety of species, genes, ecosystems, and natural processes; provides adaptation mechanisms and population control.
3. Chemical (Nutrient) Cycling: Continuous circulation of chemicals/nutrients from soil and water through organisms and back to the environment. Waste equals useful resources.
Natural Capital Framework:

$\text{Natural Capital} = \text{Natural Resources} + \text{Ecosystem Services}$

Resource Classification and Ecosystem Services

Natural Resource Categories:
- Inexhaustible Resources: Continuously renewed on long time scales (e.g., solar energy lasting 5 billion years, wind, geothermal).
- Renewable Resources: Replenished naturally within hours to decades (e.g., forests, topsoil, freshwater, fish populations).
- Sustainable Yield: The highest rate at which a renewable resource can be harvested indefinitely without reducing its available supply.
- Nonrenewable / Exhaustible Resources: Fixed crustal stocks formed over millions/billions of years (e.g., oil, coal, natural gas, copper, aluminum).
Ecosystem Services: Essential natural processes provided by healthy ecosystems at no monetary cost (e.g., air and water purification, climate regulation via carbon storage, UV protection by ozone layer, soil renewal, pest control).
Three Social / Human Principles of Sustainability:
1. Full-Cost Pricing (Economics): Inclusion of harmful environmental and health costs of goods/services directly into market prices.
2. Win-Win Solutions (Political Science): Compromise and cooperation strategies benefiting both humanity and the environment.
3. Responsibility to Future Generations (Ethics): Moral obligation to leave Earth's life-support systems in as good or better condition than inherited.
Biomimicry (Janine Benyus, 1997): Scientific discipline studying and mimicking natural designs and processes to solve human environmental problems. Key principles: life runs on sunlight, creates no waste, adapts to change, avoids unrecyclable synthetic chemicals.

Human Environmental Impact, Land Use, and Ecological Footprints

Global Wealth and Resource Distribution:
- More-Developed Countries: High income, industrialized ( $17\%$ of global population, consume $70\%$ of natural resources). The United States holds $4.3\%$ of global population and consumes $30\%$ of resources.
- Less-Developed Countries: Low/middle income ( $83\%$ of global population, consume $30\%$ of natural resources).
Human Footprint on Land: Human activities directly alter $83\%$ of Earth's land surface (excluding Antarctica).
US Federal Public Lands: Managed by federal agencies ( $28\%$ of total US land; $47\%$ of Western states; $61\%$ of Alaska):
- National Park System (NPS)
- National Forest System (USFS)
- Bureau of Land Management (BLM)
- National Wildlife Refuges (USFWS)
- National Wilderness Preservation System (strictly preserved nonmotorized access).
Ecological Footprint & Biocapacity:
- Ecological Footprint: Amount of biologically productive land and water required to supply a population with renewable resources and absorb/recycle the resulting waste and pollution.
- Biocapacity: The capacity of Earth's ecosystems to regenerate renewable resources.
- Global Ecological Deficit: In 2012, Earth's ecological footprint exceeded global biocapacity by $50\%$ (requiring 1.5 Earths). If all humans consumed at average US rates, 5 Earths would be required.

IPAT Model and Cultural Revolutions

The IPAT Impact Model (Paul Ehrlich & John Holdren):

$\text{Impact } (I) = \text{Population } (P) \times \text{Affluence } (A) \times \text{Technology } (T)$

Technology Impact Factor ( $T$ ): Can be environmental degradation technology (coal power plants, gas vehicles) or beneficial technology (solar cells, wind turbines, pollution control).
Major Cultural Changes in Human History:
1. Hunter-Gatherer Culture (10,000–12,000 years ago): Low environmental impact, nomadic.
2. Agricultural Revolution (~10,000 years ago): Domestication of plants/animals, permanent settlements, increased population.
3. Industrial-Medical Revolution (~300 years ago): Shift to urban factory production, fossil fuel reliance, rapid technological/medical advances.
4. Information-Globalization Revolution (~50 years ago): Global data transmission, rapid access to resources.
5. Sustainability Revolution (Emerging): Shifting to environmental restoration, biomimicry, and natural capital preservation.

Causes of Environmental Problems

Six Primary Causes:
1. Human Population Growth: Exponential growth ( $J\text{-shaped curve}$ ). Global population reached 7.5 billion in 2016 ( $1.20\%$ annual growth rate adding 89.8 million people/year); projected to reach 9.9 billion by 2050.
2. Affluence and Unsustainable Resource Consumption: US average consumption is 30 times higher than an average Indian and 100 times higher than individuals in the poorest nations.
3. Poverty: In 2015, 2.6 billion people lived on $3.10/day, and 1 billion lived in extreme poverty (<$1.90/day). Severe malnutrition and waterborne pathogens cause 7 million premature child deaths (<5 years) annually (19,000 deaths/day, equivalent to 95 crashing 200-passenger airliners daily).
4. Omission of Harmful Environmental/Health Costs in Market Prices: Market prices exclude external hidden costs. Gasoline market price ($2/gallon) hides $12/gallon ($3.18/liter) in external environmental/health costs, making true real cost $14/gallon.
5. Increasing Isolation from Nature: Urbanization (>50\% global, $75\%$ in developed nations) and electronic screen reliance contribute to nature deficit disorder.
6. Competing Environmental Worldviews:
  - Planetary Management: Humans are separate from nature, managing Earth for human benefit; technology will prevent resource depletion.
  - Stewardship: Humans have an ethical responsibility to manage Earth responsibly without resource waste.
  - Environmental Wisdom: Humans are part of and dependent on nature; resources are finite; success requires integrating natural principles into human actions.
  - Aldo Leopold's Land Ethic (1949): Published in A Sand County Almanac; asserts humans must act as citizens and protectors of the natural community rather than conquerors.

Economic Systems, Capital, and High vs. Low Throughput Models

Types of Capital in Economic Systems:
- Natural Capital: Earth's natural resources and ecosystem services.
- Human Capital: Physical/mental labor, organizational skills, innovation.
- Manufactured Capital: Tools, machinery, factories made from natural resources.
Economic Models:
- High-Throughput (Linear) Economy: Maximizes economic growth by increasing resource input throughput, producing high waste, pollution, and low-quality heat into global sinks.
- Low-Throughput (Circular) Economy: Biosphere-based model operating via pollution prevention, waste reduction, reuse, recycling, energy efficiency, and sustainable harvesting.

Externalities, Subsidies, and Green Taxes

Internal vs. External Costs:
- Internal Costs: Direct production/purchase costs (raw materials, labor, power, shipping, dealer profit).
- External (Hidden) Costs: Indirect environmental and health impacts (mine drainage, air pollution, medical bills, ecosystem destruction).
Subsidies: Phase out environmentally harmful subsidies (fossil fuel depletion tax breaks, timber cutting on public land) and shift to environmentally beneficial subsidies (green energy, sustainable agriculture, efficiency).
Green Taxes (Tax Shift): Lower taxes on labor, income, and wealth while increasing taxes on pollution, carbon emissions, and resource waste. Requires safety nets for low-income populations.

Environmental Policy, Laws, and Global Security

Major US Environmental Laws Enacted:
- 1969: National Environmental Policy Act (NEPA) - Required Environmental Impact Statements (EIS).
- 1970: Clean Air Act; NOAA established.
- 1972: Clean Water Act; Marine Mammal Protection Act; Federal DDT ban.
- 1973: Endangered Species Act.
- 1974: Safe Drinking Water Act.
- 1976: Toxic Substances Control Act (TSCA); Resource Conservation and Recovery Act (RCRA).
- 1977: Soil and Water Conservation Act; Federal CFC ban.
- 1980: Superfund (CERCLA) - Created hazardous waste site cleanup funds holding polluters accountable.
- 1986: Emergency Planning and Community Right-to-Know Act.
Environmental Security (Norman Myers): National security relies on watershed integrity, croplands, climate, and forest stability rather than military weaponry alone.

Sustainable Societies, Natural Income, and Principles for Living

Natural Income Concept: An environmentally sustainable society lives exclusively on renewable natural income (interest generated by Earth's natural capital) without depleting the original natural capital base.
Social Change Threshold: Historical research indicates that major social and environmental transformations require active engagement from only $5\text{--}10\%$ of a population.

Key Formulas, Mathematical Calculations, and Data Analysis

Rule of 70 (Doubling Time Formula):

$\text{Doubling Time (years)} = \frac{70}{\text{Percentage Growth Rate}}$

*   *Calculation Example*: If Oceanside grows at  $1.75\%$  annually, doubling time is:

$\frac{70}{1.75} = 40\text{ years}$

Quadrupling Population Time Calculation:
- If a population of 300,000 grows at $0.25\%$ annually, doubling time is:

$\frac{70}{0.25} = 280\text{ years}$

*   Quadrupling (1,200,000 people) requires two doublings ( $280 \times 2 = 560\text{ years}$ ).

Dimensional Analysis: Coal to Electricity Output:
- Given: $1\text{ ton coal} = 2000\text{ lbs}$ ; $12,500\text{ BTU/lb}$ ; $1\text{ kWh} = 3412\text{ BTU}$ .
- Calculation:

$1\text{ ton coal} \times \frac{2000\text{ lbs}}{1\text{ ton}} \times \frac{12,500\text{ BTU}}{1\text{ lb}} \times \frac{1\text{ kWh}}{3412\text{ BTU}} = 7327\text{ kWh}$

Rainfall Volume Calculation:
- Yard dimensions: $100\text{ ft} \times 50\text{ ft}$ ( $1\text{ ft} = 0.305\text{ m}$ ).
- Length: $100 \times 0.305 = 30.5\text{ m}$ ; Width: $50 \times 0.305 = 15.25\text{ m}$ .
- Yard Area: $30.5\text{ m} \times 15.25\text{ m} = 465.125\text{ m}^2$ .
- Rain Depth: $4.0\text{ cm} = 0.04\text{ m}$ .
- Volume: $465.125\text{ m}^2 \times 0.04\text{ m} = 18.6\text{ m}^3$ .
Per Capita Carbon Footprint Comparisons (2013 Data):
- US Per Capita $\text{CO}_2$ : 16.2 metric tons.
- Germany Per Capita $\text{CO}_2$ : 9.3 metric tons.
- Comparison Ratio:

$\frac{16.2}{9.3} = 1.74\text{ times more } \text{CO}_2 \text{ per person generated by a US citizen than a German citizen}$

Definition of Science: Interdisciplinary field discovering how nature works to predict outcomes.
Core Assumptions: Events in nature follow cause-and-effect patterns identifiable through observation, measurement, and experimentation.
The Scientific Method:
- Identify a Problem: Recognize through observation/data.
- Literature Search: Investigate existing knowledge.
- Formulate a Question: Define the specific inquiry.
- Gather Data: Conduct controlled experiments.
- Analyze Data: Look for patterns and relationships.
- Propose Hypothesis: Create a testable explanation.
- Test and Revise Hypothesis: Design experiments to test predictions and modify if unsupported.