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The water cycle (known scientifically as the hydrologic cycle) refers to the change of states between liquid, solid and gas; and to the continuous exchange of water, within the hydrosphere, between the atmosphere, land, surface water, groundwater, and plants. It may be divided into four main phases: evaporation, precipitation, infiltration and runoff.- Evaporation is generally the transfer of water from bodies of surface water to the atmosphere. Along with strict evaporation, it includes transpiration from plants; thus, it is sometimes called evapotranspiration.
- Atmospheric moisture may condense into clouds, and fall from them as precipitation. This generally occurs as rain, but snow and other forms contribute to the cycle. Precipitation seldom falls in the oceans, because under normal circumstances, mountain rangeThe most general definition of "mountain range" is a group of mountains bounded by lowlands. Mountain ranges are usually separated from other mountain ranges by passes and rivers. In the general definition, a mountain range does not necessarily have the ss are needed to induce condensation and the formation of clouds.
- Infiltration into the ground is the transition from surface water to groundwater. The infiltration rate will depend upon soil or rock permeabilityPermeability has several meanings: # In electromagnetism, permeability is the degree of magnetisation of a material in response to a magnetic field. In geology, permeability is a measure of the ability of a material to transmit fluids through it. as well as other factors. Groundwater moves very slowly, and may return as surface water or be stored within an aquiferAn aquifer is an underground layer of water-bearing permeable rock, sand, or gravel. see also groundwater). The upper boundary of the topmost (open) aquifer is known as the water table. Some areas have several aquifers, each capped on top by an impervious for thousands of years. It generally returns to the surface at lower elevations under the usual force of gravityThis article covers the physics of gravitation. See also gravity (disambiguation). Gravitation is the tendency of masses to move toward each other. The first mathematical formulation of the theory of gravitation was made by Sir Isaac Newton and proved ast, but may also rise under pressure, as in the case of an artesianAn artesian aquifer is an aquifer whose water is overpressurized. Water will thus flow out of an artesian well without pumping. Why is a well artesian? Because its recharge zone is higher than the head of the well. The Pascal's Law predicts the overpressu well.
- Runoff is the variety of ways in which surface water travels to the oceanOcean covers almost three quarters (71%) of the surface of the Earth. This global, interconnected body of salt water is divided by the continents and larger archipelagos into five oceans as follows: Arctic Ocean Atlantic Ocean Indian Ocean Pacific Ocean Ss. The water flows through riverMurray River in Australia Australia A river is a large natural waterway. It is a specific term in the vernacular for large streams, stream being the umbrella term used in the scientific community for all flowing natural waterways. In the vernacular, streas and may be delayed in lakeA lake is a large body of water, usually fresh water, surrounded by land. Large lakes are sometimes referred to as "inland seas" and small seas are sometimes referred to as lakes. For examples (of saline lakes): the Great Salt Lake, but the Dead Sea.s. Not all water completes the runoff phase; some of it evaporates before it reaches the oceans.
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Hydrologic Cycle from Earthscape
Hydrologic Cycle from GROW
