AP Environmental Science Units 4, 5, 7, and 8 Study Guide

Comprehensive review flashcards covering Earth systems, atmospheric circulation, land and water sustainability, air pollution, and waste management for AP Environmental Science.

What is insolation, and how does the angle of incidence affect it on Earth?

Insolation is incoming solar radiation, which serves as the main energy source on Earth. A perpendicular angle (equator) delivers direct light over a smaller area, while an oblique angle delivers light spread over a larger area with more energy lost as it travels.

How does albedo differ between high albedo and low albedo surfaces?

Albedo is the percentage of incoming sunlight reflected by a surface. High albedo surfaces reflect more light, absorb less, and generate less heat (e.g., white surfaces), whereas low albedo surfaces reflect less, absorb more, and produce more heat (e.g., black surfaces).

What causes Earth's seasonal changes, and what occurs during the solstices?

Seasonal changes are driven by Earth's rotation and its $23.5^\circ$ axial tilt. During the June Solstice, the Northern Hemisphere experiences summer; during the December Solstice, the Northern Hemisphere experiences winter while the Southern Hemisphere experiences summer.

What is the gaseous composition of Earth's atmosphere?

The atmosphere consists of $78.08\%\, \text{N}_2$, $20.95\%\, \text{O}_2$, and $0.97\%$ other gases, along with greenhouse gases (GHGs) like $\text{CO}_2$, $\text{CH}_4$, and $\text{N}_2\text{O}$ that trap heat to keep the planet habitable.

What are the distinguishing characteristics of the troposphere and stratosphere?

The troposphere is the ground-level, densest atmospheric layer where temperature decreases with altitude and contains "bad" tropospheric ozone. The stratosphere contains the "good" protective Ozone Layer.

How are the mesosphere, thermosphere, and exosphere characterized?

The mesosphere features a temperature drop with increasing altitude. The thermosphere is the hottest layer due to solar radiation absorption and is the site of auroras. The exosphere is the outermost layer where low Earth orbit satellites operate.

What is the difference between adiabatic cooling and adiabatic heating?

Adiabatic cooling occurs when air expands and cools as atmospheric pressure decreases during ascent. Adiabatic heating occurs when air compresses and warms as atmospheric pressure increases during descent.

What is latent heat release?

Latent heat release is the energy released when water vapor condenses into liquid water.

What are Hadley cells and the Intertropical Convergence Zone (ITCZ)?

Hadley cells are convection cells cycling air between the equator and $30^\circ\text{ N/S}$ latitudes. The ITCZ is the latitude receiving the most intense sunlight where ascending branches of Hadley cells converge.

What is the Coriolis Effect and how does it influence winds?

The Coriolis Effect is the deflection of moving objects (winds) caused by Earth's rotation, shaping prevailing wind belts such as Trade Winds and Westerlies.

What is Maximum Sustainable Yield (MSY) and at what population size does it occur?

MSY is the largest amount of a renewable resource that can be harvested indefinitely without collapsing the population. It occurs at approximately $\frac{1}{2}K$ (half of carrying capacity), where biotic potential and growth rate are highest.

What is an ecological footprint and what are its five components?

An ecological footprint is the total area of land and water required to produce consumed resources and absorb generated waste for an individual or population. Its components are carbon footprint, built-up land, forest land, cropland, and fisheries.

What is the IPAT model formula?

$$\text{Impact} = \text{Population} \times \text{Affluence} \times \text{Technology}$$

What is the Fair Earth Share per person compared to the world, US, and India averages?

The Fair Earth Share is $\approx 1.6\text{ ha/person}$. The world average is $2.8\text{ ha}$, the US average is $8.0\text{ ha}$, and the average in India is $1.2\text{ ha}$.

What are the Global Warming Potential (GWP) ratings for methane, nitrous oxide, and CFCs relative to $\text{CO}_2$?

Relative to $\text{CO}_2 = 1$, Methane ($\text{CH}_4$) has a GWP of $25$, Nitrous Oxide ($\text{N}_2\text{O}$) has a GWP of $300$, and CFCs range from $1{,}600$ to $13{,}000$.

Which six criteria pollutants are identified under the US Clean Air Act of 1970?

Sulfur Dioxide ($\text{SO}_2$), Nitrogen Oxides ($\text{NO}_x$), Carbon Monoxide ($\text{CO}$), Particulate Matter (PM), and Lead ($\text{Pb}$).

What distinguishes photochemical smog from sulfurous smog?

Photochemical smog (Los Angeles Type) is brown smog formed by solar-driven reactions of $\text{NO}_x$ and VOCs. Sulfurous smog (London Type) is gray smog consisting of sulfates and particulates from industrial coal burning.

What is a thermal inversion and why is it dangerous for air quality?

A thermal inversion is a condition where a warm air layer traps a cold air layer beneath it, locking in pollutants near the ground.

What chemical compounds cause acid deposition, and what are its environmental impacts?

Acid deposition is caused by $\text{SO}_2$ and $\text{NO}_x$ reacting in the atmosphere to form sulfuric acid ($\text{H}_2\text{SO}_4$) and nitric acid ($\text{HNO}_3$). It lowers soil and water pH beyond species' zones of tolerance and mobilizes toxic metals like aluminum.

Which specific air pollutants are targeted by vapor recovery nozzles, catalytic converters, scrubbers, and electrostatic precipitators?

Vapor recovery nozzles mitigate VOCs; catalytic converters mitigate $\text{CO}$ and $\text{NO}_x$; scrubbers remove $\text{SO}_2$ and PM; electrostatic precipitators remove PM.

What is Sick Building Syndrome, and what are key indoor air pollutants?

Sick Building Syndrome results from toxic buildup in weatherized spaces. Key indoor pollutants include radon-222 (from soil/rock; causes lung cancer), asbestos (causes cancer), mold, dust, lead, and VOCs.

What is Municipal Solid Waste (MSW), and what is its single largest component?

MSW is trash produced by households and small businesses; paper is the single largest component.

What is the primary mandate of CERCLA (Superfund Act)?

CERCLA mandates the cleanup of brownfields and hazardous waste sites.

How do individual home septic systems treat wastewater?

Septic systems utilize a septic tank to separate solids/sludge from liquid, followed by a leach field that disperses the remaining liquid into the soil.

What are the three stages of municipal sewage treatment and their functions?

1. Primary Treatment: Physical filtration and settling to remove heavy solids/sludge. 2. Secondary Treatment: Biological breakdown using aerobic bacteria and activated sludge aeration. 3. Tertiary Treatment: Advanced chemical or physical disinfection (UV light, ozone, chlorine) to kill pathogens before effluent release.