climate : The prevailing or normal pattern of weather at a place, or in a region, averaged over a long period of time; in contrast to weather, which is the state of the atmosphere at a particular time.

conductivity : A measure of the ability of a material to conduct or transmit an electric charge.

"Global Conveyor Belt": A simplified illustration of the integrated system of surface and deep-ocean currents that move waters from the polar regions, throughout the ocean, and return them to polar regions where the deep-ocean water masses form.

model : System of data, inferences, and relationships, presented as a description of a process or entity.

monsoon : A name for seasonal winds derived from the Arabic word for season, mausim. The term was originally applied to winds over the Arabian Sea that blow from the southwest during summer and the northeast during winter, subsequently extended to similar seasonal winds in other parts of the world.

practical salinity unit (psu): Used to describe the concentration of dissolved salts in water, the UNESCO Practical Salinity Scale of 1978 (PSS78) defines salinity in terms of a conductivity ratio, so it is dimensionless. Salinity was formerly expressed in terms of parts per thousand (ppt) or by weight (parts per thousand or 0/00). That is, a salinity of 35 ppt meant 35 pounds of salt per 1,000 pounds of seawater. Open ocean salinities are generally in the range between 32 and 37.

salinity : A measure of the quantity of dissolved solids in ocean water. In general, salinity reflects the total amount of dissolved solids in ocean water in parts per thousand by weight after all carbonate has been converted to oxide, the bromide and iodide to chloride, and all the organic matter oxidized. Salinity is now measured as pratical salinity units (psu).

system : 1) A regularly interacting or interdependent group of items forming a unified whole. 2) A manner of classifying. 3) A group of interacting bodies under the influence of related forces.

thermohaline circulation : The vertical movement of ocean water driven by density differences resulting from the combined effects of variations in temperature and salinity.

variability : The quality of being subject to change or deviation from a norm or standard.