Definitions Flashcards
First Law of Thermodynamics
Energy is neither created nor destroyed, but may be converted from one form to another
Second Law of Thermodynamics
When energy is changed from one form to another, some useful energy is always degraded into lower quality energy (usually heat)
Ionizing radiation
Radiation w/ enough energy to free electrons from atoms forming ions, may cause cancer (ex gamma, x-rays, UV)
High quality energy
Organized and concentrated, can perform useful work (ex fossil fuels and nuclear)
Low Quality Energy
Disorganized, dispersed (ex heat in ocean air/wind, solar
Natural Radioactive Decay
Unstable radioisotopes decay releasing gamma rays, alpha and beta particles (ex Radon)
Half-life
The time it takes for 1/2 mass of a radioisotope to decay. A radioactive isotope must be stored for approximately 10 half-lives until it decays to a safe lever
Nuclear fission
Nuclei of isotopes split apart when stuck by neutrons
Nuclear Fusion
2 isotopes of light elements (H) forced together at high temperatures till they fuse to form a heavier nucleus. Happens in the Sun, very difficult to accomplish on Earth, prohibitively expensive.
Ore
A rock that contains a large enough concentration of a mineral making it profitable to mine
Mineral Reserve
Identified deposits currently profitable to extract
Surface Mining
Cheaper, can remove more minerals, less hazardous to workers
Humus
Organic, dark material remaining after decomposition by microorganisms
Leaching
Removal of dissolved materials from soil by water moving downwards through soil
Loam
Perfect agricultural soul w/ equal portions of sand, silt, and clay
Soil conservation methods
Conservation tillage, crop rotation, contour plowing, organic fertilizers
Soil Salinization
In arid regions, water evaporates leaving salts behind (ex Fertile crescent, southwestern US)
Water Logging
Water completely saturates soil starves plant roots of oxygen, rots roots
Hydrologic Cycle Components
Evaporation, transpiration, runoff, condensation, precipitation, and infiltration
Watershed
All of the land that drains into a body of water
Aquifer
Underground layers of porous rock allow water to move slowly
Cone of Depression
Lowering of the water table around a pumping well
Salt Water Intrusion
Near the coast, over pumping of groundwater causes saltwater to move into the aquifer
ENSO
El Niño Oscillation, trade winds weaken and warm surface water moves toward Souther America. Diminished fisheries off South America, drought in western Pacific, increase precipitation in Southwestern North America, fewer Atlantic hurricanes