ENVS Final study guide

why is the ocean salty?

because of salt released from hydrothermal vents and land runoff

how and why do oxygen, CO2, and nutrient concentrations differ between the surface and deep ocean?

because photosynthetic activity is higher in surface waters, and CO2 is higher in deep waters due to respiration phytoplankton and decomposition of organic matter.

what are phytoplankton and what do they need to live?

autotrophic microscopic organisms (microalgae) that require sunlight to live and grow (photosynthesis)

what is the ocean biological pump?

collection of marine biogeochemical processes in which inorganic carbon is fixed into organic matter via photosynthesis then stored in the deep ocean.

what does dynamic equilibrium mean in a biogeochemical cycle?

balance: inputs = outputs

what are different metrics of productivity in an ecosystem?

Gross primary productivity (GPP): total C captured by plant photosynthesis, Net primary productivity (NPP): plant respiration (net carbon fixed by plants), Net ecosystem productivity (NEP): heterotrophic respiration (net carbon fixed by ecosystem)

why do plants need nitrogen and phosphorus to grow?

together they help plants grow and are essential for chlorophyll production and energy transfer. Amino acids, Nucleic acids, and phospholipids are the building blocks of cells, and require both N and P

How do plants get nitrogen?

from nitrogen fixing bacteria and decomposers

how do plants get phosphorus?

from rock weathering and decomposers

what is nitrogen fixation?

the process of converting atmospheric nitrogen (N2) into forms that plants can use (ammonia NH3)

what are some ecosystem services provided by soils?

climate regulation, medium for plant growth, water filtration and storage, nutrient cycling, habitat, carbon storage

what is the earth’s ‘critical zone’

the zone at earth’s land surface where soil interacts with rock, water, air, and living organisms.

what is soil made of

unconsolidated mineral or organic matter

what are soil horizons?

layers of soil that differ in physical, chemical, and biological properties (A, B, C horizons)

how does soil biological diversity change with temperature, pH and soil moisture

warmer temps, higher soil moisture, and neutral pH levels can promote greater diversity.

why is soil conservation important?

because it supports food production, maintains water quality, and protects the environment

how do soils help regulate the climate?

they can sequester carbon and influence local temperatures

what is the soil organic matter decomposition feedback

soil conditions with slower decomposition can reduce the carbon returned to the air

how do rates of soil erosion compare to new soil formation through weathering?

soil formation through weathering often balances or exceeds the rate of soil erosion.

what are greenhouse gasses and how do they work

substances that trap heat in the Earth’s atmosphere by re-emitting infrared radiation

where do greenhouse gases come from and how long do they last in the atmosphere

both natural and human caused emissions that can persist from a few years to a few thousand.

how much has climate warmed to date because of human activity

approximately 1.1 C or 1.9 F

what anthropogenic and natural factors have contributed to observed warming

human emissions of CO2 and fossil fuels, and volcanic eruptions and solar radiation fluctuations

what are the major sources of uncertainty that make predictions of future climate uncertain?

natural variability in the climate system, uncertainties in future human action, and incomplete understanding of Earth’s systems and their interactions

what are the consequences of warming?

more severe storms, increased drought, and destruction of certain habitats (arctic)

other than temp, what other physical evidence do we have for global warming?

rising sea levels, altered precipitation patterns, and changes in ocean acidification

where does warming happen faster and where does it happen more slowly?

it occurs faster in the arctic and over land areas that have a lower heat capacity, while it warms slower in the oceans

where do people get water

surface and groundwater including lakes, rivers, and reservoirs

what are some environmental consequences of dams?

impacts on aquatic ecosystems, changes in water temp, and alterations to water flow therefore affecting nutrient distribution

what are some environmental consequences of groundwater extraction?

cones of depression, nitrate leaching, over-pumping causing droughts and sinkholes, saltwater intrusion, and contamination from septic tanks and landfills

what is an aquifer

area underground where the soil is completely filled with water

what is water quality and what are water quality parameters?

the physical and biological characteristics of water that evaluate its suitability for various uses such as drinking, irrigation, and supporting aquatic life. Parameters are essential indicators used to evaluate this suitability such as temp, pH levels, dissolved oxygen, and more.

what human activities and natural processes potentially degrade water quality?

salt water intrusion, septic tank and landfill leaching, and chemicals used for irrigation that seep into groundwater

what is conservation of matter?

proportions of reactants and products conserved

what is conservation of energy?

energy cannot be created or destroyed (may change, but total amt stays the same)

what is residence time?

the amount of time something (substance, particle, liquid) stays inside a medium or place

how does scientific notation work?

a number between 1-10 is multiplied by a power of 10 (ex: 65,000 = 6.5 × 10³)

What is a log scale?

A method for displaying numerical data that covers a wide range of values, particularly when there are large differences in the sizes of the numbers.

what is a chemical process?

the breaking and forming of bonds between atoms

what are the subatomic particles that make up atoms and what are their charges?

protons(+), neutrons (neutral), and electrons (-)

what is an isotope and what is mass?

a variant of a chemical element that has the same number of protons but a different number of neutrons resulting in a different mass (amount of matter).

how do we balance chemical equations?

by using the principle of conservation of matter, ensuring each side of the equation is proportionate.

what are reactants?

the starting elements that undergo change

what are products?

substances formed as the result of changed reactants

what is a redox reaction

the process of electron donation and acceptance.

and how do we calculate oxidation states?

by understanding OIL RIG (oxidation is loss, reduction is gain), and knowing that anything bonded to itself =0, hydrogen is always +1, oxygen is (almost) always -2, and neutral compounds sum to 0

what is a mole?

a unit of measurement used to determine large amounts of small entities (atoms or particles)

how did the earth form?

a solar nebula which released elements to form earth

where did all the elements come from?

ancient star physics

how did the moon form?

a collision between earth and a small planet formed debris which collected in an orbit around the earth.

where did earth get its water?

through ice chunks flying into earth, as well as initial water present in its formation

what is a rock?

a collection of one or more minerals

what is a mineral?

a collection of one or more elements (atoms)

what are the three types of rock?

sedimentary, metamorphic, and igneous

what is plate tectonics and how does it explain forms of the earth’s surface?

the movement of earth’s (12 major) plates powered by hot mantle convection. Plate boundaries form earth’s surface (Transform, divergent, convergent)

what is a transform plate boundary?

plates that scrape together creating fault lines earthquakes

what is a divergent plate boundary?

plates that pull apart from each other forming rift boundaries (continent-continent boundary) and ocean ridges/underwater volcanoes (oceanic-oceanic boundary)

what is a convergent boundary?

plates that collide and form mountains (continent-continent boundary), subduction zones (oceanic-oceanic boundary/oceanic-continental boundary), and volcanoes

what are the causes of weathering?

frost/plant wedging, exfoliation/unloading [mechanical], hydrolysis, carbonation, and oxidation [chemical], burrowing and production of organic acids [biological]

what are some effects of weathering?

loss of atoms and molecules from weathered surfaces, addition of specific atoms to the weathered surface, breakdown of one mass into two or more masses

what characteristics make a thing alive?

must work to avoid decay and disorder by creating a closed system (cells), must carry information (DNA/RNA/protien), and can evolve by natural selection

where did oxygen in the earth’s atmosphere come from?

organisms used photosynthesis to release oxygen which was absorbed by oceans and seabed rock, then gassed out of ocean but absorbed by land surfaces, then accumulated in atmosphere once oxygen sinks filled up.

how is the rock cycle linked to the earth’s climate?

through weathering and its interconnectedness with the biogeochemical cycle, water cycle, and carbon cycle

what conditions on earth tend to be associated with mass extinctions?

wild swings in climate (ice sheets —> warm ocean), changes in ocean chemistry (ocean acidification, anoxia), and too much greenhouse gas

where does the sun get its energy?

nuclear fusion (hydrogen forming helium) which releases radiation (gamma rays), which are then released at the photosphere as visible light after bouncing around inside the sun and losing energy.

what types of EMR does the sun emit?

radio waves, microwaves, infrared (IR), visible light, ultraviolet (UV), X-rays, and gamma rays

how does solar radiation influlence the climate and the environment of earth?

it is absorbed by earth unevenly to drive wind bands - which drive surface currents, deep ocean currents, the water/carbon cycle, weather, and the climate.

how do we know about past ice ages?

by observing information stored in ice cores, and by noticing a 100,00 year pattern between each ice age.

what orbital processes drive past glacial cycles (Milankovitch cycles)?

eccentricity (orbit shape), obliquity (tilt), and precession (wobble)

what is electromagnetic radiation and what are the parts of the spectrum?

energy that travels and spreads out in waves- radio, microwaves, infrared, visible, uv, x-ray, and gamma rays

how does EMR interact with matter?

absorption, reflection, refraction, scattering, transmission, creation of pigments, temperature change

what types of EMR pass through the atmosphere and which are absorbed?

visible light, radio waves, some UVB, and UVA rays pass through the atmosphere while gamma, x, UVC, and infrared rays are absorbed

what is conduction and insulation?

conduction is the transfer of energy through direct contact, and insulation is the restricting process of such transfer.

what is wavelength and frequency?

wavelength is the distance between two consecutive points in a wave that is in phase, and frequency is the number of waves a vibration creates during a period of time

what is the hydrosphere and the water cycle?

the hydrosphere is the earth’s system of water. the water cycle is the movement of water in, on, and above earth - never used up but exchanged/changed/recycled (conservation of matter)

why is water polar?

because of the unequal sharing of electrons between the oxygen and hydrogen atoms within a water molecule. electrons spend more time near the oxygen and less near the hydrogen

how does water’s polarity account for so many of its special behaviors and properties?

it provides it with abilities to stick to itself and other surfaces/substances, have surface tension, and act as a solvent

what is a hydrogen bond?

the attraction of one molecule’s proton (+ charge) to another molecule’s negatively charged atom.

what are the three states of water

frozen, liquid, vapor

why is it important that water has a high heat capacity?

because it can moderate air temperature and effect the climate of a nearby region, preventing it from experiencing high temps in the summer and low temps in the winter.

why does ice float?

it is less dense than liquid water

what is cohesion and adhesion?

cohesion is the attraction of water to itself, adhesion is the attraction of water to other surfaces/substances

what is pH?

a scale that measures how acidic or alkaline a substance is. (7 being neutral)

what is ocean acidification?

the over-absorption of carbon dioxide (CO₂) in the ocean, resulting in a lower pH (more acidic)

what is stratification? why do water bodies stratify?

the phenomena where denser water (colder) sinks below less dense (warmer) water. water bodies stratify because cold water is denser than warm, and salty water is denser than fresh.

what drives upwelling?

wind patterns and the earth’s rotation

what is the difference between heat and temperature?

heat is a form of energy that is transferred through thermal conduction, convection, or radiation, while temperature is a measure of the amount of thermal energy per unit area that a body or substance gives off or absorbs.

what is the difference between power and energy?

energy is work, power is how quickly you can do the work of energy per unit time

what is an energy budget?

describes the exchange and storage of energy by an object [ie: energy in —> us (black body) —> energy out]

what are some functions of the atmosphere that help sustain life on earth?

provides us with oxygen, supports photosynthesis, protects surface from UV radiation (ozone layer)

what are pressure and density?

pressure is force exerted by the weight of air over a certain area, directly proportional to temperature. Density is the mass of air in a given volume

what is the ideal gas law?

PV = nRT (pressure, volume, amount, ideal gas constant, temp)

what is the atmosphere made of?

Nitrogen (N₂), oxygen (O₂), and lesser amts of Ar, Ne, He, Kr, Xe

what are the layers of the atmosphere

troposphere (lowest/thinnest), stratosphere (ozone layer), mesosphere & thermosphere (high temp, not high heat constant)

what is ozone and why and where is it beneficial/harmful?

O₃ (O₂ + O), it is the highest concentration in the stratosphere. It is beneficial due to its protection of the surface from UV radiation. It is harmful in that it contributes to photochemical smog, effecting people and vegetation.

what are aerosols?

particulate matter- small solid particles and liquid droplets.

what are hadley cells and how does the atmosphere redistribute solar energy?

large-scale convection cells that redistribute heat on earth to combat the unequal heating of earth.

what is the El Nino southern oscillation

a recurring climate pattern involving changes in the temperature of waters in the central and eastern tropical pacific ocean.

what is the difference between climate and weather?

climate is the long term patterns/average of conditions (max/min avg temps, rain and snowfall, seasonality), while weather is the short-term patterns of conditions (temp, precipitation, wind speed and direction, sunlight, etc)

how do climate patterns create biomes?

they determine the vegetation that grows in a particular region