Exam 2 Flashcards
Boyle’s Law
A relationship stating that, with temperature held constant, the pressure and volume of a gas are inversely proportional. In other words, the product of pressure and volume is a constant.
Buoyancy
: A tendency of an object to float, rise, or sink when submerged in a fluid.
Charles’s Law
A relationship stating that, with pressure held constant, the volume and temperature of a gas are directly proportional. In other words, the quotient of volume and temperature is a constant.
Condensation
The process by which a gas becomes a liquid.
Convergence
The inward movement of air or water to a region in the atmosphere or ocean.
Coriolis Effect
The apparent tendency for a fluid (air or water) moving across earth’s surface to be deflected from its straight-line path. Fluids are deflected to the right of their initial path in the Northern Hemisphere and to the left in the Southern Hemisphere.
Deserts
Areas of low rainfall, generally less than 250 mm per year. Deserts may be warm (such as those located in the subtropics) or cold (as in the central plateau of Antarctica).
Divergence
The outward movement of air or water from a region in the atmosphere or ocean.
Evaporation
The process by which a liquid is converted to a gas.
Groundwater
Water that penetrates through soil and rock and collects below the surface.
Hadley Circulation
The process by which an air mass under- goes convergence at the tropics and divergence at about 30 degrees N or 30 degrees S latitude in one large convection cell.
Hydrologic cycle
The major reservoirs of water in the Earth system and the pattern of water storage and movement throughout that system.
Intertropical Convergence zone (ITCZ)
A region of the tropics where surface heating causes uplift in the atmosphere, allowing subtropical air to flow inward to produce a convergence zone. This zone moves north and south of the equator as the seasons change.
Latent heat of fusion
The energy required to effect a change of phase between a solid and a liquid. Converting a solid to a liquid requires an addition of energy; converting a liquid to a release energy to the environment.
Latent heat of vaporization
The energy required to effect a change of phase between a liquid and a gas. Converting a liquid to a gas requires an addition of energy; converting a gas to a liquid releases energy to the environment.
Monsoon
A seasonal reversal in the surface winds caused by large- scale differential heating of land and ocean surfaces. Monsoon circulation is defined by the wind fields but usually also has a direct impact on rainfall.
Obliquity
The angle of a planet’s spin axis relative to a line drawn perpendicular to the plane of the planet’s orbit around the Sun: also called tilt.
Partial pressure
In a mixture of gases, the pressure a gas would exert if it were the only gas present (i.e., the contribution of each individual gas to the total pressure exerted by the mixture).
Polar front zone
A zone of step temperature gradients formed at approximately 60 degrees N and 60 degrees S latitude, where cold, polar air meets the warm air moving poleward form the subtropics
Subsidence
The sinking of air from higher levels in the atmosphere down toward the surface. Also the vertical movement of Earth’s crust toward the mantle.
Uplift
Any Process by which air is forced to rise upward in the atmosphere. Also an upward vertical tectonic movement of earth’s crust.
Absolute vorticity
The sum of the planetary and relative vorticities experienced by a moving fluid.
Antarctic Bottom Water (AABW)
Bottom water that forms in the Weddell Sea off Antarctica. The AABW circles Antarctica and flows northward as the deepest layer in the Atlantic, Pacific, and Indian ocean basins
Atomic Number
The number of protons in the nucleus of an atom. All atoms of a given element have the same atomic number.
Bottom water
Very dense, cold water that forms along the edges of sea ice in certain areas near the poles and subsides, making up the bottom layer of ocean water as it circulates throughout the world’s ocean.
Downwelling:
The sinking of surface water caused by convergence and water accumulation at the surface.
Ekman spiral
Describes the tendency for surface ocean water to be deflected to the right (left) of the layer above it in the northern (southern) hemisphere due to the Coriolis Effect. Each layer is moved by the layer above so that the deeper below the surface the further each layer is deflected to the right or left, producing a spiraling effect with depth.
Ekman transport
The net direction of transport in the water column as a result of the Ekman spiral. The movement is at 90 degrees to the wind direction (to the right in the Northern Hemisphere and to the left in the Southern Hemisphere).
El Nino
Originally, a warm ocean current that appears off the coast of Peru and Ecuador shortly after Christmas and flows for only a few weeks; the name now describes a major shift in the oceanic circulation that occurs in this region every 2 to 10 years.
El Nino-Southern Oscillation (ENSO)
A climate event in the tropical Pacific Ocean in which the main area of surface convection moves from the western to the central; Pacific. This event is associated with large-scale changes in the ocean circulation, the atmospheric circulation, and tropical precipitation patterns. The effects of an ENSO event may also spread beyond the tropics, causing anomalous weather conditions in many midlatitude locations.
Evaporite deposit
Mineral deposit formed by the evaporation of seawater from shallow seas. The remaining salts are concentrated and precipitate from solution.
Geostrophic current
A current that flows around oceanic gyres; produced where the Coriolis Effect that deflects the flow into the center of a gyre is balanced by the downslope flow from the higher sea-surface elevations in the gyre center. The resulting flow is clockwise in the Northern Hemisphere (counterclockwise in the Southern Hemisphere), approximately parallel to the ocean slope, and in the same direction as the wind driven flow.
Gyre
A large, circular circulation pattern in the ocean. Gyres in the Northern Hemisphere circulate clockwise, whereas those in the Southern Hemisphere circulate counterclockwise.
Half-life
The time it takes for half the initial quantity of radioactive isotope to decay.
Halocline
A steep salinity gradient in the pycnocline zone that marks the transition between the surface and the deep ocean. Salinity rises rapidly with increasing depth in the halocline.
Isotope
Atoms of a given element that have different numbers of neutrons in their nuclei.
La Nina
The opposite phase of the Southern Oscillation from El Nino conditions. It represents a stronger or more extreme version of the “normal” circulation in the tropical Pacific.
Mass number
The combine number of protons and neutrons in the nucleus of an atom.
Mixed layer
The surface layer of the ocean that is mixed by wind action.
North Atlantic Deep Water (NADW)
Cold, dense water that forms in the northernmost Atlantic Ocean, sinks, and flows southward at depth into the rest of the Atlantic Ocean.
Planetary vorticity
The angular rotation about a vertical axis at Earth’s surface brought about because of Earth’s rotation.
Pycnocline
A steep density gradient (caused by changing temperature, salinity, or both) that marks the transition between the surface zone and the deep ocean. On the order if a kilometer in thickness, it is characterized by a rapid downward increase in density. The steep density gradient in the Pycnocline zone makes this layer very stable.
Radiocarbon dating
A particular type of radiometric age dating that uses the half-life of 14C to date materials that contained living organisms. It has been used to date materials back to about 50,000 years ago.
Radiometric age dating
A method of calculating the age of a sample if material by knowing the half-life of a radioisotope within it. This method has provided absolute dates for the geologic time scale and for other specific events in Earth’s history.
Relative vorticity
Vorticity producing by processes (other than Earth’s rotation) that induce a rotary motion in a fluid (such as clockwise or counterclockwise surface wind patterns acting on the ocean surface or current shear in the oceans).
Southern Oscillation (SO)
An oscillation in sea-level pressure between the western and central/eastern portions of the tropical Pacific Ocean.
Southern Oscillation Index (SOI)
A measure of the pressure difference between the western and central eastern parts of the tropical Pacific Ocean. Strong negative value indicate ENSO conditions, whereas strong positive values indicate La Nina (non-ENSO ) conditions.
Stable isotope
An isotope that does not spontaneously change into another isotope or into an atom of another element by radioactive decay.
Thermohaline circulation
The circulation of the deep oceans; driven by density differences that result from variations in temperature and salinity.
Unstable isotope
An isotope that spontaneously changes into another isotope or into an atom of another element by radioactive decay.
Upwelling
The rising of coolers, nutrient- rich ocean water to the surface to replace warm, divergent surface water.
Vorticity
The tendency of a fluid to undergo rotary motion. A tendency for counterclockwise motion is referred to as positive vorticity; a tendency for clockwise motion is negative vorticity.
