Abstract:
The hydrologic cycle under the driving force of the Sun is a continuous process by which water is transported from the oceans to the sea, It extends across a wide spectrum of space and time scales and through the storage and release of latent heat accompanying phase change, it affects the global circulations of atmosphere and ocean, in turn affecting weather and climate. Due to water's properties as a solvent, the hydrological cycle is not only the integrating process for the fluxes of water and energy but also for some chemical substances. The vital role of water in the evolution and operation of Earth's system provides the rationale for hydrology being considered as a geoscience. Its aim is to investigate and understand natural phenomena as opposed to mere solutions of various adhoc engineering, agricultural and other water related problems. Hydrology is thus an earth science, which encompasses the occurrence, distribution, movement
and properties of the waters of the earth and their environmental relations, It
interfaces with allied fields of geology, climatology, meteorology, oceanography
and glaciology. It has not only to deal with complex processes of the natural
hydrological cycle, but also influence of man's activities and intervention in almost every aspect of hydrological cycle.
