EVS Final

Scientific Method

A process of observation, hypothesis, experimentation, data collection, and conclusion.

Albedo

The reflectivity of a surface; high albedo = more reflection and cooling.

Positive Feedback

A process that amplifies change (e.g., ice melting reduces albedo → more warming).

Negative Feedback

A process that stabilizes a system (e.g., sweating cools the body).

Universe

All space, time, matter, and energy.

Big Bang Theory

The origin of the universe; supported by red shift and cosmic microwave background radiation.

Red Shift

Wavelengths stretched as galaxies move away, showing the universe is expanding.

Cosmic Microwave Background

Leftover radiation from the Big Bang.

Electromagnetic Spectrum

Range of radiation: gamma → X-ray → UV → visible → IR → microwave → radio.

Solar System Formation (Nebular Hypothesis)

A rotating cloud of gas/dust collapsed to form the Sun and planets.

Terrestrial Planets

Small, rocky planets (Mercury, Venus, Earth, Mars).

Jovian Planets

Large gas giants with low density (Jupiter, Saturn, Uranus, Neptune).

Earth's Core

Iron/nickel; outer core liquid, inner core solid.

Mantle

Hot, semi-solid rock layer beneath the crust.

Crust

Thin, solid outer layer of Earth.

Atom

Smallest unit of matter.

Proton

Positively charged particle in the nucleus.

Neutron

Neutral particle in the nucleus.

Electron

Negatively charged particle orbiting the nucleus.

Molecule

Two or more atoms bonded together.

Compound

A molecule with atoms of different elements.

Crystal

Solid with a repeating, orderly atomic structure.

Mineral

Naturally occurring, inorganic solid with definite chemical composition and crystal form.

Rock

A solid made of minerals.

Igneous Rock

Formed from cooled magma or lava.

Sedimentary Rock

Formed from compacted sediments.

Metamorphic Rock

Rock changed by heat and pressure.

Rock Cycle

The processes that transform rock types into others.

Alfred Wegener

Proposed continental drift.

Paleomagnetism

Magnetic minerals record Earth's magnetic field direction.

Magnetic Reversals

Switches in Earth's magnetic polarity; symmetrical stripes on ocean floor show spreading.

Divergent Boundary

Plates move apart; typically mid-ocean ridges.

Convergent Boundary

Plates collide; subduction or mountain building.

Transform Boundary

Plates slide past one another (e.g., San Andreas Fault).

Subduction Zone

Oceanic crust sinks beneath another plate.

Convection

Movement in mantle that drives plate motion.

Asthenosphere

Soft, partially molten upper mantle layer.

Lithosphere

Crust + rigid upper mantle.

Hot Spot

Stationary mantle plume; creates volcanic chains (Hawaii).

Earthquake

Caused by sudden movement along faults.

Focus

Location inside Earth where an earthquake begins.

Epicenter

Point on Earth's surface above the focus.

P-Waves

Fast waves that travel through solids and liquids.

S-Waves

Slower waves that travel only through solids.

Richter Scale

Measures earthquake magnitude.

Weather

Short-term atmospheric conditions.

Climate

Long-term patterns of weather.

UV Absorption by Ozone

Stratospheric ozone absorbs harmful ultraviolet radiation.

Greenhouse Gases

COI, CHI, NIO, water vapor; trap infrared radiation.

Troposphere

Lowest layer of atmosphere; weather occurs here.

Stratosphere

Layer containing the ozone layer.

Relative Humidity

Amount of water vapor relative to what air can hold at that temperature.

Specific (Absolute) Humidity

Actual amount of water vapor (g/kg air).

Saturation

Air holding maximum moisture.

Supersaturation

More water vapor than saturation; leads to clouds.

Why Air Rises

Density lifting, frontal lifting, orographic lifting, convection.

Wind

Movement of air from high to low pressure.

Coriolis Effect

Deflects moving air right in the Northern Hemisphere.

Hadley Cell

Tropical circulation; rising air near equator causes rain.

Polar Cell

Cold sinking air near poles.

Ferrel Cell

Mid-latitude circulation.

ITCZ (Intertropical Convergence Zone)

Area near equator with rising air and heavy rainfall.

Ecosystem

Interaction of organisms with their physical environment.

Trophic Levels

Feeding steps in an ecosystem (producers → consumers).

Biomagnification

Increase in toxin concentration up the food chain.

Water Cycle

Evaporation → condensation → precipitation → runoff.

Where Earth's Water Is Stored

Most in oceans; some in ice (cryosphere) and groundwater.

Ocean Salinity Controls

Evaporation increases; rainfall and rivers decrease.

Ocean Layers

Mixed layer, intermediate layer, deep ocean.

Biological Pump

Movement of carbon to deep ocean via organisms.

Ekman Spiral

Wind + Coriolis create surface water movement and upwelling.

El Niño

Warming of Pacific Ocean; weak trade winds; stops upwelling.

El Niño Frequency

Occurs every 2-7 years.

Population

Number of people in a region.

Fertility Rate

Average number of births per woman.

Demographics

Statistical characteristics of populations.

Population Pyramid

Graph representing age and sex distribution.

Fossil Fuels

Energy sources from ancient organic matter.

Coal

Solid fossil fuel from plants.

Coal Pros

Cheap, abundant.

Coal Cons

Dirty, high COI emissions.

Petroleum

Liquid hydrocarbons used for fuel.

Natural Gas

Mainly methane; cleaner fossil fuel.

U-235 and U-238

Isotopes of uranium; U-235 is more radioactive.

Nuclear Power

Uses fission to heat water and generate electricity.

Nuclear Pros

Clean, no foreign dependence, long supply.

Nuclear Cons

Toxic waste, leak risk, terrorism concerns.

Renewable Energy

Energy sources replenished naturally.

Types of Renewables

Geothermal, solar, wind, biomass.

Geothermal Energy

Uses Earth's heat; location-limited.

Wind Energy

Clean energy; could supply 30% of U.S. electricity.

Solar Energy

Energy from sunlight; clean but variable.

Hard Energy Path

Large-scale, centralized fossil fuels & nuclear.

Soft Energy Path

Decentralized, renewable technologies.

Carbon Cycle

Movement of carbon between atmosphere, oceans, land, and organisms.

Carbon Reservoirs

Atmosphere, oceans, fossil fuels, carbonates.

Carbon Fluxes

Photosynthesis, respiration, combustion.

Fossil Fuel Flux Importance

Adds COI rapidly → climate change.

Past Climate Evidence

Ice cores, sediments, historical records.

Climate Change Evidence

Melting ice, rising seas, warming oceans, glacial retreat.