APES: Test 1

Briefing Document: Earth's Systems and Resource Extraction

This briefing document synthesizes key concepts from lectures on atmospheric and oceanic circulation (wind cells) and notes on mining practices, highlighting their interconnections and environmental implications.

I. Earth's Energy Distribution and Atmospheric Circulation

The Earth's tilt on its axis is the primary driver of seasons and varying energy transfer across the globe.

  • Direct vs. Indirect Sunlight: "The more direct light, the more energy transfer." Conversely, at an extreme angle, there is "less energy." This explains why "the equator... is hot because it gets a lot of direct" sunlight, while poles receive indirect light.

  • Albedo: The reflectivity of a surface, known as "albedo," plays a crucial role in heat absorption. Surfaces with "high albedo" are "reflecting a lot of light," keeping them cool, while low albedo surfaces absorb more energy. This concept applies to natural surfaces (like snow and ice) and human choices (e.g., "wearing a black shirt, you're going to get hot, right? Wearing lighter clothes.").

  • Convection Currents: Heat transfer in fluids, including air, occurs through convection. Warm fluid rises, cools, and sinks, creating a "circular motion." However, Earth's rotation prevents a simple pole-to-equator convection cell.

  • Coriolis Effect: This effect, caused by the Earth's rotation and varying rotational speeds at different latitudes, deflects moving objects (like wind and ocean currents). "Parts of the earth are moving faster than others." The equator rotates faster than the poles. This deflection is to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.

  • Global Wind Cells: The interplay of direct solar energy, convection, and the Coriolis effect creates three major wind cells in each hemisphere:

  • Hadley Cell: Driven by "hot air rising at the equator," which spreads out, cools, and sinks around 30 degrees latitude. This rising air also brings "moisture... so on the planet you have rising air like here at the equator and the moisture that was in it came out," leading to high rainfall.

  • Polar Cell: Driven by "cold air sinking at the pole" (between 60 and 90 degrees latitude), which spreads out and then rises around 60 degrees latitude. "Sinking air dry."

  • Ferrel Cell: This middle cell (between 30 and 60 degrees latitude) "exists only because the other two exist." It is indirectly driven by the circulation of the Hadley and Polar cells.

II. Mining and Resource Extraction

The Earth's crust is primarily composed of oxygen, while the atmosphere is mainly nitrogen. Mining involves extracting valuable resources (ore) from the Earth.

  • Mining Types:Surface Mining: Involves "removal of the earth on top of resources to access minerals." It is generally "safer but causes more habitat destruction." Examples include Open-Pit Mining, Dredging, Area Strip Mining, and Contour Strip Mining. Mountain top removal is an extreme form where operators "blast the top off a mountain to retrieve minerals."

  • Subsurface Mining: Involves "digging underground creating tunnels and rooms underground to obtain minerals." This causes "less direct habitat destruction, but much more dangerous." Examples include underground coal mining, long walling, and room and pillar methods.

  • Mining Vocabulary:Overburden: "Rock and soil over a desired resource (basically habitat)."

  • Spoils: "Disturbed earth left over from removing overburden."

  • Ore: "Rock that contains a valuable resource (mixture of resource, rock and other solids)."

  • Gangue: "The part of the ore that is not the desired resource (waste)."

  • Tailings: "The leftover material from separating the gangue from the valuable material (theoretically all gangue, but traces minerals remain). Often stored in tailing ponds."

III. Environmental Impacts of Mining

Both surface and subsurface mining have significant environmental consequences.

  • Surface Mining Impacts:"Disruption of habitat and land surface."

  • "Increased erosion from loss of vegetation and disruption of soil."

  • "Wind or water erosion of toxin-laced waste."

  • "Acid mine drainage."

  • "Loss of wildlife due to habitat loss/fragmentation and toxic releases."

  • "Most surface mining land can be restored but is costly and never quite the same."

  • Specific to Mountain Top Removal: "Explosion: air pollution, noise pollution, earthquakes. In general: Loss of mountain habitat, topography changes and loss of vegetation. Difficult to remediate due to poor soil conditions in mountainous areas."

  • Subsurface Mining Dangers:"Mine Collapse."

  • "Black lung disease."

  • "Ventilation problems leading to gas buildups" (CO/CO2 causing suffocation, Methane/hydrogen sulfide/Coal dust leading to explosion).

  • Acid Mine Drainage (AMD): A significant environmental issue, AMD occurs "when rocks are exposed to the elements (wind and water) acid runoff is created."

  • Process: Water flowing through mine tailings collects sulfuric acid and iron deposits, then "acidic water leaches out of mining areas into watersheds," contaminating water supplies and "decreases pH of surface waters."

  • Chemistry: Pyrite (FeS2), often found in coal beds, reacts with water to release iron and sulfate ions. "Sulfate ions increase the number of H+ ions in water, decreasing the pH of the water." This "acidic pH increases the leaching of toxic metals into the water (Pb, Hg, and Cu)," severely impacting aquatic life. "Yellow boy," an Iron(III) hydroxide precipitate, can also form, choking aquatic life and blocking sunlight.

  • Treatment: AMD can be treated through "lime neutralization" (adding lime/limestone to increase pH) or "constructed wetlands" designed to neutralize the acidic runoff.

IV. Mining Regulations

The Surface Mining Control and Reclamation Act aims to mitigate environmental damage by requiring that "land must be minimally disturbed" and "land must be returned to original state" after mining operations.

Briefing Document: Global Wind Cells and Energy Transfer

Date: October 26, 2023 Subject: Review of Earth's Energy Dynamics, Seasons, Albedo, Coriolis Effect, and Global Wind Cells

This briefing document summarizes key concepts related to Earth's energy transfer, seasonal variations, surface reflectivity, and the formation of global wind cells, as presented in the provided source material.

Main Themes and Key Ideas:

1. Earth's Tilt and Seasons:

  • Core Concept: The Earth's tilt on its axis is the primary cause of seasons.

  • Mechanism: When a hemisphere is tilted towards the sun, it receives more direct sunlight, leading to greater energy transfer and warmer temperatures (summer). Conversely, when a hemisphere is tilted away, sunlight hits at a more extreme angle, resulting in less energy transfer and colder temperatures (winter).

  • "The more direct light, the more energy transfer in the winter. at an extreme angle and less energy."

  • Equatorial Focus: The equator consistently receives the most direct sunlight, making it a hot region year-round.

  • "on the planet that direct sunlight at the equator. The equator that is why it is hot because it gets a lot of direct and that means where is it indirect? lot of energy. This explains both the season."

2. Albedo and Surface Reflectivity:

  • Definition: Albedo is a measure of how much light a surface reflects.

  • Impact: Surfaces with a high albedo reflect a lot of light, keeping them cool because they absorb less energy. Surfaces with a low albedo absorb more energy and tend to be warmer.

  • "And we have a special word for that because it's called albido. If you have a high albct Reflecting a lot of light keeps it cool because it's not absorbing that energy."

  • Examples: Lighter-colored clothing and reflective car shades are examples of high albedo surfaces used to keep cool. Conversely, dark surfaces like a black shirt in the sun absorb more heat.

3. Convection Currents:

  • Basic Principle: Convection currents involve a fluid (like air or water) being heated, rising, cooling, sinking, and creating a circular motion.

  • "in a nutshell, convection current as heat source air fluid rises and then it sinks and then you end up with this circular motion."

  • Global Context: While the equator is hot and the poles are cold, a single large convection current in each hemisphere does not form due to the Coriolis effect.

4. The Coriolis Effect:

  • Cause: The Coriolis effect is a result of the Earth's rotation, with different parts of the Earth rotating at different speeds. The equator moves fastest, while the poles move slowest.

  • "The reason why we don't have that is due to something called effect happens because the earth is moving and parts of the earth are moving faster than others."

  • Impact on Movement: Objects (like wind or ocean currents) moving across the Earth's surface retain the velocity from their starting location. As they move towards a faster or slower moving part of the Earth, their path appears to curve.

  • "So those are the south they retain their velocity that they have at their starting location. So here they're moving faster but they're just curve here with Santa Claus."

  • Directional Deflection:Northern Hemisphere: Winds and currents are deflected to the right.

  • Southern Hemisphere: Winds and currents are deflected to the left (opposite direction).

5. Global Wind Cells:

The combination of the Coriolis effect and differential heating (hot air rising at the equator, cold air sinking at the poles) creates three major wind cells in each hemisphere:

  • a. Hadley Cell:

  • Location: Approximately between 0° and 30° latitude.

  • Driver: "driven by hot air rising at the equator."

  • Process: Hot, moist air rises at the equator, moves poleward in the upper atmosphere, cools, sinks around 30° latitude (creating high-pressure systems), and returns to the equator as trade winds.

  • Impact on Climate: Rising air at the equator brings moisture and leads to rain, explaining why rainforests are found there. Sinking, dry air at 30° contributes to desert formation.

  • "at the equator that's why you get You're going to see more rain. Where do you see air? That's why we have less which is what showing air only but"

  • b. Polar Cell:

  • Location: Approximately between 60° and 90° latitude.

  • Driver: Cold air sinking at the poles.

  • Process: Cold, dense air sinks at the poles, spreads out towards the equator, warms and rises around 60° latitude, and returns to the poles in the upper atmosphere.

  • Impact on Climate: Sinking air at the poles is dry.

  • c. Ferrel Cell:

  • Location: Approximately between 30° and 60° latitude.

  • Driver: "This wind is driven by the other thing it is moving that way and this air is moving that You'll end up with the air in the middle also rotating."

  • Dependence: "This exists only because the other two exist." It is indirectly driven by the interaction and circulation patterns of the Hadley and Polar cells. It involves air rising at 60° (pulled up by the polar cell) and sinking at 30° (pulled down by the Hadley cell).

Briefing Document: Terrestrial Biomes

This document summarizes key information about various terrestrial biomes, drawing from the provided lecture excerpts. It highlights their defining characteristics, climate patterns, and typical vegetation and animal adaptations.

I. Introduction to Biomes

  • Definition: Biomes are classified by precipitation and temperature. While animals can migrate, making them less reliable indicators, the types of plants present (vegetation) are crucial for classification.

  • Disturbed Conditions: Some ecosystems are characterized by "very disturbed conditions," suggesting a dynamic and perhaps unpredictable environment.

II. Climate and Key Biome Classifications

The lecture emphasizes the importance of precipitation and temperature patterns in defining biomes.

  • Precipitation Variation: Examples like "Hilo Hawaii" (high rainfall) and "Phoenix" (low rainfall) illustrate the wide range of precipitation across different locations. "Seattle rain" is also mentioned as a characteristic, though "inpal weather" is noted as being "beautiful."

  • Temperature Variation: Biomes can range from consistently "warm all the time" to those experiencing "very distinct seasons" with periods "mostly below freezing."

III. Specific Biome Characteristics

A. Tropical Rainforest

  • Climate: "Warm all the time." Experiences rain "almost every day."

  • Vegetation: Trees "grow tall." High biodiversity is indicated by "This is really high university. We don't even know."

  • Nutrient Cycling: Nutrients "go into the very works because recycle" rapidly due to frequent rain.

B. Tropical Seasonal Forest (Monsoon Forest)

  • Climate: Also called "seasonal season," characterized by periods "without much rainy and dry." It has "a period where it rains a lot [and] where it doesn't rain."

  • Vegetation: "Short trees and grasses."

  • Water Factor: Experiences a significant "dry season."

C. Desert (Subtropical Desert)

  • Climate: "Warm dry" conditions found in either the northern or southern hemisphere. "Low precipitation."

  • Vegetation: Dominated by "succulent that are adapted to water," possessing "wax water and close" to conserve moisture.

  • Animal Adaptations: "A lot of animals" are present, suggesting specific adaptations to arid conditions.

D. Temperate Rainforest

  • Location: Exemplified by the "Pacific Northwest United States."

  • Climate: Features "seasonal rainfall" but does not have "totally dry" periods. Seattle is a characteristic location.

E. Temperate Seasonal Forest (Deciduous Biome)

  • Climate: Experiences "very distinct seasons." This distinct seasonality "requires adaptations by the animal."

  • Vegetation: Characterized by "deciduous" trees, which suggests leaf shedding in response to seasonal changes.

F. Chaparral (Mediterranean Climate)

  • Location: Classic examples include "Southern California."

  • Climate: Characterized by "mild temperatures, but they have a rainy season and a dry season."

  • Human Impact: The dry season and associated issues are linked to "people," implying human influence on these environments.

G. Savannah

  • Climate: "Warm and dry and dry." Also referred to as a "may" biome (likely a mis-transcription, possibly referring to a type of grassland or savanna).

  • Precipitation: Experiences "low precipitation," though "not as low as it never goes below" a certain threshold.

  • Vegetation: Primarily composed of "grasses."

H. Grasslands

  • Location: Described as "the area where we do most of our" (implying agriculture or human activity).

  • Precipitation: Has a "decent amount of precipitation."

  • Vegetation: The plants are "ever" (likely evergreen or persistent), and "the soil can be some plants are okay fast."

I. Tundra

  • Climate: "Mostly below freezing except for this tiny little when you have a fall." Growth occurs for only "four months of the year."

  • Soil: "The soil is often frozen."

Briefing Document: Ocean Currents and Climate Phenomena

This briefing summarizes key concepts related to ocean currents, upwelling, and major climate oscillations (El Niño and La Niña), drawing from the provided lecture excerpts.

1. Ocean Currents: The Global Transport System

Ocean currents are crucial for transporting nutrients and regulating global climate. They are broadly categorized into deep ocean currents and surface currents.

  • Deep Ocean Currents (Thermohaline Circulation / "Conveyor Belt"):

  • Driven by differences in temperature and salinity ("thermal" and "haline").

  • Characterized by "really, really cold, really salty water" found "all over the planet."

  • Importance: "Deep ocean currents are really important because they transport nutrients around the globe." They are also responsible for the global distribution of cold, salty water.

  • Surface Currents:

  • Occur at "the very top part of these kinds of [oceans]."

  • Primarily "moved around by the wind."

  • Also shaped by the Coriolis effect, leading to a "shape that currents make" (gyres).

  • Generally transport "warm ocean water." For example, warm water is found on the east side of the Atlantic Ocean and the west side of the Pacific Ocean due to these currents.

2. Upwelling: Bringing Nutrients to the Surface

Upwelling is a critical process for marine ecosystems.

  • Mechanism: Upwelling "occurs when it [deep water] brings with it a lot of [nutrients] to the surface."

  • Significance: "That is called places where you have you're going to have more nutrients for the producers." This leads to "more net primary productivity" (NP). Regions with significant upwelling, such as off the coast of continents, are highly productive.

3. El Niño-Southern Oscillation (ENSO): A Global Climate Driver

The El Niño-Southern Oscillation (ENSO) describes a natural oscillation in the Pacific Ocean that significantly impacts global climate. It cycles between normal, El Niño, and La Niña conditions. "This is totally normal" and "not related to climate change," though "climate change can exacerbate the impact."

3.1. Normal Year Conditions

In a normal year in the South Pacific:

  • Trade Winds: "Trade winds... are blowing from the Americas towards Asia." These winds are consistent and strong.

  • Ocean Conditions: Off the coast of South America, there is "a lot of good fishing" due to upwelling. Over Asia, "you'll get a lot of moisture," leading to "rainy weather."

3.2. El Niño Conditions

El Niño (abbreviated ENSO) is characterized by:

  • Ocean Temperature: The "surface of the South Pacific is unusually warm." This is the primary diagnostic for scientists.

  • Trade Winds: The "trade winds pretty much do what they're not supposed to do." They "either stop or they go the other way. Or maybe they go the same way that they normally do, they're just lessen."

  • Impacts:

  • "Less upwelling over by the [Americas]."

  • "Less rainy" on the side that would normally get more rain (Asia).

  • "This impacts weather around the globe. So impacts our global [conditions]." While specific impacts vary, "every event is different," and a comprehensive list of effects would be "ridiculous to memorize everything."

3.3. La Niña Conditions

La Niña is the opposite of El Niño:

  • Ocean Temperature: The "surface of the ocean in the South Pacific... is cold."

  • Trade Winds: The "trade winds are really strong."

  • Impacts: "All the things we wrote down for El Niño is going to be the opposite."

  • "More upwelling."

  • "More rain."

  • Similar to El Niño, "the impacts of this are global," affecting weather patterns worldwide, though "every year is a little bit different."

3.4. Predictability of ENSO

The fluctuation between El Niño and La Niña is not perfectly predictable. While they oscillate, the timing and severity are variable. "Every scientist will say it doesn't really work that way" in terms of precise predictability of how many events or how bad they will be.

4. Rain Shadow Effect

The lecture also briefly mentions the Rain Shadow Effect:

  • Mechanism: "This happens when you wind the wind blowing winds over the ocean. If they hit a mountain can't go over it. You're going to get a lot of rain that happens as one side [windward]. on the other side [leeward], it's pretty dry."

  • Terminology: The dry side is called the "rain shadow."

Aquatic Biomes Briefing Document

This briefing document reviews the main themes and most important ideas and facts presented in the "Aquatic biomes recording .m4a" source. It aims to provide a clear understanding of various aquatic biomes, their characteristics, ecological services, and human impacts.

I. Fundamental Classifications and General Concepts

The classification of aquatic biomes often hinges on several key characteristics:

  • Salinity: Distinguishes between freshwater (lakes, ponds, rivers) and saltwater (oceans, estuaries, coral reefs, some wetlands).

  • Flow Rate: Varies from "pretty minimal" in lakes and ponds to "faster than others" in rivers.

  • Depth: A "very subjective" classification, but crucial for determining light penetration and oxygen levels.

  • Nutrient Levels: A significant concern, with "fertilizers [being] a big problem" in some freshwater systems.

  • Light Penetration: Directly influences the presence of photosynthetic life, making "shallow" areas vital for primary production.

  • Oxygen Supply: Predominantly at the surface from the atmosphere, or from oxygenating plants. Low oxygen levels are a concern in deeper, less agitated waters.

II. Freshwater Biomes

A. Lakes

  • Salinity: Fresh water.

  • Flow Rate: "Pretty minimal."

  • Depth: Considered "deep," which impacts light penetration and oxygen levels at the bottom.

  • Key Concerns: Low oxygen supply at the bottom, and significant issues with "nutrients," particularly "fertilizers."

  • Organisms: Creatures live on the bottom, often in dark, low-oxygen conditions.

B. Ponds

  • Salinity: Fresh water.

  • Flow Rate: "Not a lot of [flow]."

  • Depth: "Shallow."

  • Key Characteristics: Similar to lakes but shallower, allowing for more light penetration. Can develop unpleasant smells if nutrient-rich and stagnant.

C. Rivers

  • Salinity: Fresh water.

  • Flow Rate: "Faster than others" compared to lakes and ponds.

  • Key Characteristics: "Carry nutrients that's helpful" to ecosystems. However, they "can also carry polluting" substances, leading to "problems."

  • Human Impacts: "We build dams" which "changes ecosystem[s]" and can impede "migration."

III. Transitional and Brackish Biomes

A. Wetlands

  • Depth: "Pretty shallow."

  • Salinity: Can be freshwater or saltwater; "salty one has wetland."

  • Defining Feature: Water-saturated areas, either permanently or seasonally.

  • Ecological Services (Wetland Services):Important Breeding Grounds: Support a "large number" of species.

  • Purify Water: "Clean it up" as "water flows through and flows out the other end."

  • Groundwater Recharge: Water flows "all the way down into an aquifer." Removing wetlands leads to "less water" recharge.

  • Carbon Sink: "Store a lot of [carbon]; they absorb more carbon than they give off."

  • Flood Control: "Absorb the water that's there" during "events," protecting "nearby areas."

  • Ecotourism: People "go there watching" wildlife, contributing to economic value.

B. Mangrove Swamps (A Type of Wetland)

  • Location: Found in "trop[ical]" regions.

  • Defining Feature: Characterized by "mangroves [that] will grow" and can tolerate being "fully submerged in the water or fully exposed." This is "not normal for like water" plants.

  • Ecological Service: "These trees are really great at protect[ing coastlines]" (implied: from erosion and storms).

C. Estuaries

  • Defining Feature: "An area where a river meets the ocean."

  • Salinity: "Highly variable conditions" due to the mixing of freshwater from rivers and saltwater from the ocean. "The amount of salt that river can bring a lot more fresh."

  • Organisms: Organisms living here "are well adapted to these highly variable conditions," making the area "really [biologically diverse]."

  • Ecological Services: "They protect us against fish and birds" (likely meaning they provide habitat for these). Many "fishal shallow" species are found here, crucial for food chains.

IV. Marine Biomes (Ocean)

A. Coral Reefs

  • Flow Rate: "Out[ward] flow" (implied: currents).

  • Depth: "Shallow" enough for "light [to] penetrate."

  • Ecological Services:Store Carbon Dioxide: Contribute to carbon sequestration.

  • Barrier Protection: "A barrier that protects coastlines from storms."

  • Massive Habitat: "A massive habitat for a lot of different organisms," providing "a habitat for a lot of things."

  • Economic Value: "Produce a lot of our global fish" (fisheries), and support "ecotourism." They are also a source for "aquarium fish that are saltwater fish."

B. Ocean Zones

  • Pelagic Zone: The open ocean.

  • Benthic Zone: "The bottom of any ecos[ystem]" (ocean or lake).

  • Photic Zone: "Shallow enough where sunlight" penetrates. This zone is rich in "sunlight and nutrients" and is found on "the continental shelf and like opener. Yeah. Over here on the continental shelf closer to the shoreline."

V. Riparian Zones

  • Location: "Not exactly in the water. It's over here with the biomet," referring to the land adjacent to a river or other water body.

  • Importance: "Really important if you want to have a healthy aquatic system."

  • Ecological Services:Water Purification: "They'll clean up the water a little bit."

  • Pollutant Absorption: "They'll absorb some of the pollutants."

  • Erosion Control: "Hold on to [soil]."

VI. Other Important Concepts

  • Nutrient Cycling: Rivers "carry nutrients that's helpful," and these nutrients, "if not absorbed there, [are] eaten in the water." This highlights the interconnectedness of aquatic systems.

  • Human Impact (Dams): "We build a dams migration. It changes ecosystem." This illustrates a significant human alteration of river biomes.

  • Tidal Zones: Areas influenced by tides, where organisms must "live in [this] zone" and adapt to fluctuating water levels.