Terms : Hide Images
| 12078031318 | Highly developed countries | Countries with complex industrialized bases, low rates of population growth, and high per person incomes | 0 | |
| 12078031319 | moderately developed countries | developing countries with a medium level of industrialization and average per capita incomes that are lower than those of highly developed countries | 1 | |
| 12078031320 | less developed countries | Also known as developing country, a country that is at a relatively early stage in economic development | 2 | |
| 12078031321 | renewable resources | resources provided by nature that can replace themselves within a relatively short period of time | 3 | |
| 12078031322 | nonrenewable resources | resources that are often formed by very slow geologic processes, so we consider them incapable of being regenerated within the realm of human existence. | 4 | |
| 12078031323 | ecological footprint | The amount of biologically productive land and water needed to support a person or population. | 5 | |
| 12078031324 | environmental sustainability | the ability to meet the current human need for natural resources without compromising the ability of future generations to meet their needs | 6 | |
| 12078031325 | global commons | Those parts of our environment available to everyone but which no single individual owns -the atmosphere, fresh water, forests, wildlife, and ocean fisheries. | 7 | |
| 12078031326 | green roofs | roofs partially or completely covered by plants | 8 | |
| 12078031327 | stewardship | responsibility for conserving and restoring the Earth's resources for future generations | 9 | |
| 12078031328 | environmental science | the study of how humans interact with the environment of living and nonliving things. | 10 | |
| 12078031329 | ecology | the branch of biology concerned with the relations between organisms and their environment | 11 | |
| 12078031330 | system | any set of interacting components that influence one another by exchanging energy or materials | 12 | |
| 12078031331 | ecosystem | collection of all the organisms that live in a particular place, together with their nonliving environment | 13 | |
| 12078031332 | dynamic equilibrium | A form of equilibrium where opposing forces balance each other out, and the system as a whole does not change. | 14 | |
| 12078031333 | negative feedback mechanism | one change triggers a second change which slows or reverses the original change | 15 | |
| 12078031334 | positive feedback mechanism | one change triggers a second change which speeds up, reinforces, or enhances the original change | 16 | |
| 12078031335 | hypothesis | a prediction that can be tested | 17 | |
| 12078031336 | control group | in an experiment, the group that is not exposed to the treatment; contrasts with the experimental group and serves as a comparison for evaluating the effect of the treatment. | 18 | |
| 12078031337 | theory | a scientific explanation supported by much evidence collected over a long period of time | 19 | |
| 12078031338 | cyanobacteria | Photosynthetic, oxygen-producing bacteria (formerly known as blue-green algae). | 20 | |
| 12078031339 | externality | The cost or benefit of a good or service that is not included in the purchase price of that good or service. | 21 | |
| 12078031340 | ecosystem services | benefits to humans provided by natural systems | 22 | |
| 12078031341 | marginal cost of pollution | the additional cost imposed on society by an additional unit of pollution. | 23 | |
| 12078031342 | marginal cost of abatement | the cost associated with reducing a small additional amount of pollution. | 24 | |
| 12078031343 | natural capital | the natural resources and natural services that keep us and other species alive and support out economies | 25 | |
| 12078031344 | estuary | an area where fresh and salt water mix | 26 | |
| 12078031345 | biotic | the living organisms in an ecosystem | 27 | |
| 12078031346 | abiotic | nonliving, physical features of the environment, including air, water, sunlight, soil, temperature, and climate | 28 | |
| 12078031347 | population | a group of organisms of the same species that live in the same geographic area at the same time | 29 | |
| 12078031348 | community | all the different species that share some degree of mutual interdependence and that live together in the same habitat | 30 | |
| 12078031349 | landscape | region including several interacting ecosystems | 31 | |
| 12078031350 | biosphere | the part of the Earth's atmosphere, oceans, land surface and soil containing all its living organisms | 32 | |
| 12078031351 | potential energy | stored energy | 33 | |
| 12078031352 | kinetic energy | energy of motion | 34 | |
| 12078031353 | First Law of Thermodynamics | energy is neither created nor destroyed although it can be changed from one form to another | 35 | |
| 12078031354 | Second Law of Thermodynamics | when energy is converted from one form to another some of it is always converted into a lower-quality, less usable form. Thus with each energy transformation, less energy is available to do work. | 36 | |
| 12078031355 | producers | synonym for autotroph; an organism which makes its own food converting inorganic substances into organic substances | 37 | |
| 12078031356 | autotrophs | synonym for producer; an organism which makes its own food converting inorganic substances into organic substances | 38 | |
| 12078031357 | consumer | synonym for heterotroph; an organism which feeds on other organisms to obtain nutrients and energy | 39 | |
| 12078031358 | heterotroph | synonym for consumer; an organism which feeds on other organisms to obtain nutrients and energy | 40 | |
| 12078031359 | primary consumer | synonym for herbivore; organism which feeds on plants | 41 | |
| 12078031360 | herbivore | synonym for primary consumer; organism which feeds on plants | 42 | |
| 12078031361 | secondary consumer | an organism that eats herbivores | 43 | |
| 12078031362 | tertiary consumer | an organism that eats secondary consumers | 44 | |
| 12078031363 | omnivores | organisms that eat both plants and animals | 45 | |
| 12078031364 | detritus feeders | synonym for detritivores; organism that eats dead, decaying organic matter | 46 | |
| 12078031365 | detritivores | synonym for detritus feeders; organism that eats dead, decaying organic matter | 47 | |
| 12078031366 | decomposers | synonym for saprotrophs; bacteria and fungi that break down organic matter and use the products of decomposition for food | 48 | |
| 12078031367 | saprotrophs | synonym for decomposers; bacteria and fungi that break down organic matter and use the products of decomposition for food | 49 | |
| 12078031368 | trophic level | level in a food chain | 50 | |
| 12078031369 | biomass | the total mass of all organisms in an ecosystem | 51 | |
| 12078031370 | gross primary productivity (GPP) | The total amount of solar energy that producers in an ecosystem capture via photosynthesis over a given amount of time. | 52 | |
| 12078031371 | Net Primary Productivity (NPP) | gross primary productivity minus the losses due to respiration | 53 | |
| 12078031372 | evolution | genetic changes that occur in a population over time due to 1 )natural variation in genes within a population; 2) the fact that generally more organisms are produced than will survive to maturity; 3) those best adapted are more likely to survive; and 4) characteristics that increase survival odds become more common over time due to natural selection | 54 | |
| 12078031373 | natural selection | process by which individuals that are better suited to their environment are more likely to survive to reproduce and pass on these traits to their offspring; also called survival of the fittest | 55 | |
| 12078031374 | mutation | change in the genes that may be due to random copying errors or the effects of radiation or mutagenic chemicals | 56 | |
| 12078031375 | kingdom | broadest level of classification (unless you consider Domains Archaea, Bacteria and Eukarya). Generally all life is divided into 6 kingdoms (Archaea, Bacteria, Protista, Plantae, Fungi and Animalia) | 57 | |
| 12078031376 | succession | change in ecosystems that occur over time | 58 | |
| 12078031377 | primary succession | succession that occurs on surfaces where no soil exists | 59 | |
| 12078031378 | secondary succession | change in the species composition that exists in an area over time when one type of community replaces another | 60 | |
| 12078031379 | climax community | this stage of succession has been reached when a stable and persistant community develops. It will a major disturbance like fire,hurricane, or deforestation to change the community. | 61 | |
| 12078031380 | pioneer community | organisms (generally lichen) which start succession where soil did not previously exist | 62 | |
| 12078031381 | symbiosis | close relationships or associations between species; includes mutualism, commensalism and parasitism | 63 | |
| 12078031382 | Mutualism | symbiotic relationship which benefits both species (example: coral and zooxanthellae) | 64 | |
| 12078031383 | commensalism | symbiotic relationship that benefits one organism and neither harms nor helps the other organism (ex: epiphytes such as mosses on a tree) | 65 | |
| 12078031384 | parasistism | symbiotic relationship where one organism benefits by getting nourishment from another species but, though it may weaken it, does not generally kill it. | 66 | |
| 12078031385 | intraspecific competition | competition between individuals of the same species (a population) | 67 | |
| 12078031386 | interspecific competition | competition between individuals of different species | 68 | |
| 12078031387 | symbionts | partners in a symbiotic relationship | 69 | |
| 12078031388 | coevolution | The mutual evolutionary influence between two different species interacting with each other and reciprocally influencing each other's adaptations. | 70 | |
| 12078031389 | predation | consumption of one organism (the prey) by another (the predator) | 71 | |
| 12078031390 | pathogen | an organism that can cause disease | 72 | |
| 12078031391 | competition | the struggle between organisms to survive in a habitat with limited resources | 73 | |
| 12078031392 | habitat | the environment used by a species or population | 74 | |
| 12078031393 | niche | description of an organism's adaptations, habitat, use of resources and relationships with other organisms | 75 | |
| 12078031394 | fundamental niche | the range of conditions that a species can potentially tolerate and the range of resources it can potentially use if there is no competition from other species | 76 | |
| 12078031395 | realized niche | the part of its fundamental niche that a species actually occupies when there is competition from other species | 77 | |
| 12078031396 | limiting resource | resources that due to scarcity (or overabundance) restricts or limits the niche of a species | 78 | |
| 12078031397 | resource partioning | species that have similar niches will often reduce interspecific competition by not utilizing the resources in exactly the same way. For example, different species of birds may use of different parts of a tree when hunting for insects. Hawks and owls reduce competition by feeding at different times (day vs night) | 79 | |
| 12078031398 | keystone species | a species whose impacts on its community or ecosystem are much larger and more influential than would be expected from mere abundance | 80 | |
| 12078031399 | biodiversity | The number of different species in an area | 81 | |
| 12078031400 | ecotone | a transitional zone where ecosystems meet | 82 | |
| 12078031401 | biogeochemical cycle | the cycling of chemical elements or compounds through the atmosphere, hydrosphere, biosphere, and lithosphere | 83 | |
| 12078031402 | combustion | rapid oxidation of organic molecules, rapid reaction between oxygen and fuel that results in fire. | 84 | |
| 12078031403 | nitrogen fixation | conversion of N2 to ammonia (NH3) by nitrogen-fixing bacteria or by lightening, combustion, industrial processes or volcanic activity | 85 | |
| 12078031404 | nitrification | conversion of ammonia (NH3) and ammonium (NH4+) to nitrates (NO3-) by soil bacteria | 86 | |
| 12078031405 | assimilation | absorption of nitrates, ammonia or ammonium and conversion into plant proteins and nucleic acids | 87 | |
| 12078031406 | ammonification | the conversion of biological nitrogen compounds (proteins and amino acids) into ammonia and ammonium ions. | 88 | |
| 12078031407 | denitrification | the reduction of nitrate to N2 | 89 | |
| 12078031408 | hydrologic cycle | water cycle | 90 | |
| 12078031409 | transpiration | evaporation of water from leaves | 91 | |
| 12078031410 | runoff | water running over the surface of the ground | 92 | |
| 12078031411 | watershed | all the land drained by a body of water | 93 | |
| 12078031412 | groundwater | water occupying cracks and pores in the ground | 94 | |
| 12078031413 | photochemical smog | brownish orange haze formed by chemical reactions involving sunlight, nitrogen oxides, and hydrocarbons. Some of the pollutants in photochemical smog include peroxyacetyl nitrates (PANs), ozone, and aldehydes | 95 | |
| 12078031414 | acid deposition | sulfur dioxide and nitrogen dioxide emissions that react with water vapor in the atmosphere to form acids that return to the surface as either dry or wet deposition. | 96 | |
| 12078031415 | aerosols | tiny solid particles or liquid droplets that remain suspended in the atmosphere for a long time | 97 | |
| 12078031416 | coriolis effect | the tendency of moving air or water to be deflected from its path to the right in the Northern Hemisphere and to the left in the Southern Hemisphere as a result of the rotation of the Earth | 98 | |
| 12078031417 | prevailing winds | major surface wind that blows more or less constantly | 99 | |
| 12078031418 | gyres | a large circular pattern of surface ocean currents found in each ocean basin; forms due to global wind patterns and earth's rotation | 100 | |
| 12078031419 | upwelling | a rising ocean current that carries cold, nutrient-rich water to the surface | 101 | |
| 12078031420 | lithosphere | Earth's outermost rigid rock layer that is composed of seven major and several minor plates | 102 | |
| 12078031421 | athenosphere | The soft layer of the Mantle on which the tectonic plates move | 103 | |
| 12078031422 | plate tectonics | the study of the processes by which the lithospheric plates move over the asthenosphere | 104 | |
| 12078031423 | plate boundary | region where two tectonic plates meet | 105 | |
| 12078031424 | subduction | process by which one tectonic plate descends under an adjacent plate | 106 | |
| 12078031425 | seismic waves | vibrations that move through rock as a result of an earthquake | 107 | |
| 12078031426 | faults | a fracture in the crust along which rock moves forward and backward, up and down, or side to side. Faults are often found along plate boundaries. | 108 | |
| 12078031427 | focus | the place within the Earth that an earthquake originates | 109 | |
| 12078031428 | epicenter | the location on the surface of the Earth directly above the focus | 110 | |
| 12078031429 | magma | molten rock found within the Earth | 111 | |
| 12078031430 | lava | molten rock that has reached the surface of the Earth | 112 | |
| 12078031431 | biome | large, relatively distinct terrestrial region with a similar climate, soil, plants and animals regardless of its location in the world | 113 | |
| 12078031432 | permafrost | soil that is permanently frozen | 114 | |
| 12078031433 | monoculture | growing only one species | 115 | |
| 12078031434 | desertification | conversion of land to desert | 116 | |
| 12078031435 | alpine | mountain | 117 | |
| 12078031436 | salinity | salt concentration | 118 | |
| 12078031437 | plankton | free-floating organisms in aquatic ecosystems that are carried by currents | 119 | |
| 12078031438 | phytoplankton | photosynthetic plankton such as diatoms and cyanobacteria | 120 | |
| 12078031439 | zooplankton | animal plankton such as jellyfish, protozoa, krill, and also larvae of many organisms including shrimp, crabs, lobsters, barnacles | 121 | |
| 12078031440 | nekton | organisms that are relatively strong swimmers such as whales, most fish, and turtles | 122 | |
| 12078031441 | benthos | bottom-dwelling organisms such as worms, clams, scallop, sea stars, lobsters | 123 | |
| 12078031442 | headwater streams | small, cool, fast flowing streams that are feed a river and are its source | 124 | |
| 12078031443 | flood plain | flat areas along a river bank that are prone to flooding | 125 | |
| 12078031444 | tributaries | rivers which feed into a larger river | 126 | |
| 12078031445 | delta | low lying plain formed by sediments deposited at the mouth of a slow-moving river | 127 | |
| 12078031446 | limnetic zone | open water farther from shore than the littoral zone and extending down to the depth reached by sunlight | 128 | |
| 12078031447 | profundal zone | deeper areas of a lake which light does not reach | 129 | |
| 12078031448 | zooxanthellae | algae that live in the tissues of coral animals and carry out photosynthesis | 130 | |
| 12078031449 | intertidal zone | region between low tide and high tide marks | 131 | |
| 12078031450 | pelagic environment | all ocean water from the shoreline to the deep sea floor (divided into the neritic and oceanic provinces) | 132 | |
| 12078031451 | euphotic zone | zone of the ocean where there is enough light to support photosynthesis | 133 | |
| 12078031452 | neritic province | part of the pelagic environment that overlies the ocean floor from the shoreline to a depth of 200 m | 134 | |
| 12078031453 | oceanic province | open ocean that does not lie over the continental shelf | 135 | |
| 12078031454 | bycatch | fish, birds, sea turtles, dolphins and other organisms unintentionally caught in nets and other fishing gear | 136 | |
| 12078031455 | aquaculture | farming aquatic organisms (mussels, salmon, oysters, etc) | 137 | |
| 12078031456 | persistence | characteristic describing the stability of chemicals. Persistent chemicals are very slow to break down and may remain in the environment for many years. | 138 | |
| 12078031457 | bioaccumulate | the accumulation of toxic chemicals in an organism, often the chemicals are stored in fatty tissue | 139 | |
| 12078031458 | biological magnification | the increase in the concentration of chemicals in the tissues as the chemical moves through the food chain; organisms higher in the food chain have higher concentrations of chemicals that bioaccumulate | 140 | |
| 12078031459 | hormones | chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another | 141 | |
| 12078031460 | endocrine disrupter | chemicals that mimic or interfere with the function of the endocrine system in humans or wildlife | 142 | |
| 12078031461 | toxicant | chemicals harmful to human health | 143 | |
| 12078031462 | acute toxicity | harmful effects that occur shortly after exposure to a toxic chemical | 144 | |
| 12078031463 | chronic toxicity | harmful effects that result from extended exposure to a toxin or long after an exposure to a toxin | 145 | |
| 12078031464 | response | when used in reference to toxins, it is the harmful effect or damage resulting from exposure to a toxin | 146 | |
| 12078031465 | LD50 or lethal dose 50% | the amount of a chemical that kills 50% of the animals in a test population | 147 | |
| 12078031466 | ED50 or effective dose-50% | the dose of toxin that affects 50% of the population (the effects may be beneficial as in pain relief OR harmful as in causing vomiting). | 148 | |
| 12078031467 | TC50 or toxic concentration-50% | compare with the TD50 except exposure is generally by inhalation or contact. | 149 | |
| 12078031468 | carcinogen | cancer causing chemical (carcinogenic chemical) | 150 | |
| 12078031469 | toxicology | study of the effects of toxic chemicals on health | 151 | |
| 12078031470 | epidemiology | the study of populations of people to assess the effects of chemicals and diseases on health | 152 | |
| 12078031471 | additive effects | when the combined effects of a mixture of chemicals is the sum of their individual effects | 153 | |
| 12078031472 | synergistic effects | combined effects of two pollutants are greater than the sum of their separate effects | 154 | |
| 12078031473 | antagonistic effect | one chemical interferes with the action of another | 155 | |
| 12078031474 | dispersal | movement of individuals from one region to another (includes immigration and emigration) | 156 | |
| 12078031475 | immigration | movement of individuals into an area | 157 | |
| 12078031476 | emigration | movement of individuals out of an area | 158 | |
| 12078031477 | intrinsic rate of increase (biotic potential) | maximum rate a population can increase under ideal conditions | 159 | |
| 12078031478 | exponential growth | accelerating growth that results from a constant rate of change over time (produces a J-shaped growth curve as the populations grows faster and faster the larger it gets) | 160 | |
| 12078031479 | environmental resistence | limits to population size set by factors such as the availability of food, water, space, shelter and limits set by disease | 161 | |
| 12078031480 | carrying capacity (K) | the maximum population a particular environment can sustainably support for an indefinite period of time | 162 | |
| 12078031481 | logistic population growth | an S-shaped population growth curve that results when small populations no where near the carrying capacity grow very rapidly then level off at or near the carrying capacity | 163 | |
| 12078031482 | density-dependent factors | environmental factors whose effects on a population increase as the population density increases (Examples: disease, predation, competition for food) | 164 | |
| 12078031483 | density-independent factors | environmental factors whose effects on a population are not influenced by the density of the population (Examples: flood, fire, hurricanes) | 165 | |
| 12078031484 | survivorship | the probability a given individual will survive to a particular age | 166 | |
| 12078031485 | demography | branch of sociology that involves the study of population statistics and describes the populations of countries, regions and ethnic groups of people | 167 | |
| 12078031486 | demographic transition | the demographic stages a country goes through as it changes from a preindustrial society to an industrial society | 168 | |
| 12078031487 | age structure | a description of the proportion and number of people in each age class in a population | 169 | |
| 12078031488 | total fertility rate | average number of children borne per woman during her lifetime | 170 | |
| 12078031489 | food insecurity | condition in which people live in hunger or fear of hunger | 171 | |
| 12078031490 | economic development | expansion of a government's economy; seen by many as the best way to raise the standard of living | 172 | |
| 12078031491 | culture | ideas and customs of a group of people at a given period of time. It is passed on from generation to generation but evolves over time. | 173 | |
| 12078031492 | family planning services | Services that enable men and women to limit family size, safeguard individual health rights, and improve the quality of life for themselves and their children | 174 | |
| 12078031493 | population growth momentum | continued growth of a population after the fertility rate decreases as a result of having a large percentage of the population in pre-reproductive and reproductive years | 175 | |
| 12078031494 | pronatalist | a person who is in favor of population growth | 176 | |
| 12078031495 | energy density | the amount of energy contained in a given volume or mass of an energy source | 177 | |
| 12078031496 | hydrocarbon | molecules containing only carbon and hydrogen | 178 | |
| 12078031497 | resource recovery | process of removing material such as sulfur or heavy metals from emissions or solid waste and selling it as a resource of value | 179 | |
| 12078031498 | fluidized-bed combustion | A clean-coal technology in which crushed coal is mixed with limestone and burned in a strong current of air; reduces SOx and NOx emissions | 180 | |
| 12078031499 | structural traps | underground geologic structures that trap oil or gas if it is present | 181 | |
| 12078031500 | synfuel | A liquid or gaseous fuel synthesized from coal or other naturally occurring sources and used in place of oil or natural gas. | 182 | |
| 12078031501 | fossil fuels | coal, oil, and natural gas | 183 | |
| 12078031502 | methane | CH4; the primary component of natural gas and a powerful greenhouse gas | 184 | |
| 12078031503 | energy efficiency | using less energy to accomplish a given task (ex: designing more fuel-efficient automobiles or light bulbs) | 185 | |
| 12078031504 | cogeneration | simultaneous production of two useful forms of energy from the same fuel Ex: using coal to generate electricity and using the waste heat to heat buildings | 186 | |
| 12078031505 | hydraulic fracturing (fracking) | Pumping chemicals, water, and sand under high pressure into underground rock to recover natural gas or oil | 187 | |
| 12078031506 | tar sands | mixture of clay, sand, water and bitumen. Bitumen (a thick asphalt-like material) can be extracted and refined into oil. | 188 | |
| 12078031507 | boreal forest (taiga) | biome limited to the northern hemisphere, coniferous trees (spruce and fir) with waxy needles to reduce water loss, cold and long winters | 189 | |
| 12078031508 | temperate deciduous forest | moderate rainfall spread out fairly evenly through year, dominant vegetation deciduous trees (lose their leaves during winter) such as oak and maple, cold winters and warm summers | 190 | |
| 12078031509 | grassland | dominant vegetation is grass and other nonwoody plants, hot to warm summers and cool to cold winters, less precipitation than temperate forests but more than deserts, frequent fire | 191 | |
| 12078031510 | chaparral | mild winters with abundant rainfall, very dry summers, dominant vegetation is shrubs and small trees with small, leathery leaves to reduce water loss | 192 | |
| 12078031511 | tundra | long cold winters, permafrost, lichens and low growing plants are dominant vegetation, also scattered stunted trees and shrubs | 193 | |
| 12078031512 | desert | very low precipitation, may be very hot or cold depending on latitude, dominant plants are cacti, many animals are nocturnal | 194 | |
| 12078031513 | tropical rainforest | warm year round, rainy season and dry season but overall high precipitation and enough rain falls even during the dry season to support forest growth, poor soil, extremely high biodiversity | 195 | |
| 12078031514 | temperate rainforest | high annual precipitation, cool but not cold winters, coastal fog, characterized by large, long lived evergreens such as Douglas fir and Western hemlock, found in a few limited areas including the Pacific northwest coast | 196 | |
| 12078031515 | savanna | warm year round, seasonal rainfall with extended dry periods, dominant vegetation is grasses with scattered trees | 197 | |
| 12078031516 | tropical dry forest | warm year round but with an extended dry season, dominant vegetation is deciduous trees that have small leaves they lose during the dry season | 198 | |
| 12078031517 | nuclear energy | energy released by the fission or fusion of the nuclei of atoms | 199 | |
| 12078031656 | fission | splitting the nuclei of atoms into smaller fragments and in the process releasing large amounts of energy | 200 | |
| 12078031657 | fusion | fusing together the nuclei of small atoms into a larger atom of a different element and in the process releasing large amounts of energy | 201 | |
| 12078031658 | atomic number | number of protons in a atom (a unique number for each element) | 202 | |
| 12078031659 | mass number | the sum of the number of neutrons and protons in an atom | 203 | |
| 12078031660 | isotope | forms of an element that have different mass numbers | 204 | |
| 12078031661 | radioactive decay | the breakdown of unstable nuclei that is accompanied by the release of radiation (alpha particles, beta particles, and gamma rays) | 205 | |
| 12078031662 | enrichment | the process of refining uranium ore to increase the concentration of U-235 | 206 | |
| 12078031663 | breeder reactor | type of nuclear power plant in which nonfissionable U-238 is converted into fissionable Pu-239 | 207 | |
| 12078031664 | spent fuel | used fuel elements from a nuclear reactor | 208 | |
| 12078031665 | low-level radioactive waste | radioactive solids, liquids or gases that give off small amounts of ionizing radiation | 209 | |
| 12078031666 | high-level radioactive waste | radioactive solids, liquids or gases that give off large amounts of ionizing radiation | 210 | |
| 12078031667 | infrared energy | heat | 211 | |
| 12078031668 | passive solar heating | using the sun's energy without using mechanical devices to distribute the heat | 212 | |
| 12078031669 | active solar heating | using a series of collectors to absorb the sun's energy and pumps or fans to distribute the collected heat | 213 | |
| 12078031670 | solar thermal electric generation | producing electricity by the use of mirrors or lenses to concentrate sunlight and heat a fluid-filled pipe or Stirling engine | 214 | |
| 12078031671 | photovoltaic solar cell | converts sunlight directly to electricity | 215 | |
| 12078031672 | biomass | plant material, including undigested fiber in animal waste, used as fuel | 216 | |
| 12078031673 | wind energy | electric or mechanical energy obtained from wind (resulting from the uneven heating of the surface of the Earth creating differences in atmospheric pressure) | 217 | |
| 12078031674 | hydropower | generation of electrical or mechanical energy from falling or flowing water | 218 | |
| 12078031675 | geothermal energy | use of energy from within the Earth's interior for space heating or the generation of electricity | 219 | |
| 12078031676 | tidal energy | use of the ebb and flow of tides to generate electricity | 220 | |
| 12078031677 | energy conservation | using less energy by reducing use and waste (ex: carpooling, reducing driving speeds, or shutting off lights that are not in use) | 221 | |
| 12078031678 | fuel cell | device that directly converts chemical energy into electricity without needing to produce steam and use a turbine and generator. Fuel cells use combine the fuel (hydrogen) with oxygen from the air | 222 | |
| 12078031679 | alpha particles | a type of ionizing radiation | 223 | |
| 12078031680 | half-life | The time required for half the atoms in a sample of a radioactive isotope to decay. | 224 | |
| 12078031681 | deforestation | the temporary or permanent conversion of forests to land for agriculture, suburban development or other uses | 225 | |
| 12078031682 | landscape ecology | the study of ecological processes over large areas and multiple ecosystems found in a region | 226 | |
| 12078031683 | biosphere | parts of the Earth that contain living organisms | 227 | |
| 12078031684 | open system | A system in which matter and energy can enter from or escape to the surroundings. | 228 | |
| 12078031685 | closed system | a self-contained system that does not exchange energy or matter with its surroundings | 229 | |
| 12078031686 | gross primary productivity | the total amount of energy captured and assimilated by plants by photosynthesis in a given period of time | 230 | |
| 12078031687 | net primary productivity | the rate at which organic matter accumulates into plant tissue | 231 | |
| 12078031688 | El Nino-Southern Oscillation (ENSO) | periodic, large-scale warming of surface waters of the tropical eastern Pacific Ocean that affects both oceanic and atmospheric circulation patterns | 232 | |
| 12078031689 | metapopulation | a group of spatially separated populations of the same species | 233 | |
| 12078031690 | endocrine disruptor | a chemical that mimics or interferes with the actions of the endocrine system | 234 | |
| 12078031691 | brownfields | an urban area of abandoned, vacant buildings and lots whose redevelopment is hindered due to possible contamination | 235 | |
| 12078031692 | food desert | neighborhoods with little access to nutritious, fresh foods | 236 | |
| 12078031693 | urban heat island | local heat buildup in areas of high population density | 237 | |
| 12078031694 | dust dome | dome of heated air surrounding urban areas that contains higher concentration of air pollution | 238 | |
| 12078031695 | compact development | design of cities in which tall, multiple-unit residential buildings are close to shopping and jobs, and all are connected by public transport | 239 | |
| 12078031696 | suburban sprawl | expansion of human populations away from central urban areas into low-density and usually car-dependent communities | 240 | |
| 12078031697 | payback time | time needed to recover the cost of an investment through energy savings and longer product life | 241 | |
| 12078031698 | smart grid | efficient, self-regulating electricity distribution network that accepts any source of electricity and distributes it automatically to end users | 242 | |
| 12078031699 | zero net energy buildings | buildings that produce as much or more energy than they use | 243 | |
| 12078031700 | subsidies | government support (such as public financing or tax breaks) of businesses or institutions to promote that group's business or activity | 244 | |
| 12078031701 | acid mine drainage | pollution caused when sulfuric acid and dissolved chemicals such as lead, arsenic, and cadmium flow from coal and metal mines into nearby lakes and streams | 245 | |
| 12078031702 | moderator | often water, it slows neutrons so they are traveling at the proper speed to split U-235 atoms | 246 | |
| 12078031703 | vitrification | solidifying liquid high-level radioactive by mixing it with molten glass | 247 | |
| 12078031704 | primary air pollutant | a harmful substance released directly into the atmosphere | 248 | |
| 12078031705 | secondary air pollutant | a harmful substance that forms in the atmosphere as a result of chemical reactions between primary air pollutants or other chemicals normally found in the atmosphere | 249 | |
| 12078031706 | particulates | solid or liquid particles suspended in the air | 250 | |
| 12078031707 | hydrocarbons | compounds containing only hydrogen and carbon | 251 | |
| 12078031708 | mobile sources | pollution from cars, trucks, planes and other sources of transportation | 252 | |
| 12078031709 | stationary sources | air pollution from power plants, homes, industries, etc. | 253 | |
| 12078031710 | ozone | pale blue gas that is a secondary pollutant in the troposphere but shields us from UV in the stratosphere | 254 | |
| 12078031711 | volatile organic compounds (VOCs) | organic compounds that evaporate easily at room temperature | 255 | |
| 12078031712 | temperature inversion (thermal inversion) | when a layer of cold air is trapped beneath a layer of warm air causing air pollutants to accumulate close to ground level | 256 | |
| 12078031713 | ultraviolet radiation | part of the electromagnetic spectrum with wavelengths that are just shorter than visible light | 257 | |
| 12078031714 | Montreal Protocol | an international agreement to phase out the use of CFCs and other ozone depleting chemicals | 258 | |
| 12078031715 | global distillation effect | the process whereby volatile chemicals evaporate from land as far away as the tropics and are carried by air currents to higher latitudes where they condense and fall to the ground. | 259 | |
| 12078031716 | cap and trade | The government allots permits to businesses to emit certain amounts of pollution. Companies can choose whether to use their permit to emit pollution or to reduce their emissions and sell their permit. Over time, the cap shrinks and less pollution is permitted. | 260 | |
| 12078121901 | Paris Agreement | agreement signed by 195 countries in 2015 to limit climate change to below 2 degrees C above pre-industrial levels | 261 |
