What's Hydrology

"Hydrology is the science which deals with the waters of the earth, their occurrence, circulation and distribution on the planet, their physical and chemical properties and their interactions with the physical and biological environment, including their responses to human activity." (UNESCO,1964)

A Water cycle in nature is called "the Hydrologic Cycle". Hydrology is the study of this water cycle on the earth.
Hydrology treats precipitation, snow, ice, evapotranspiration, surface flow, erosion and acuumulation, water quality, and systems of water resources and their interactions.
Precipitation and evapotranspiration have been a main topics of meteology, and now they are also included in the subjects of hydrology as important processes of water cycle.

Hydrology is devided into two parts. One is Regional Hydrology, which treats mainly waters in regional scale, from precipitation like rainning and snowing to running off to sea. The other is Global Hydrology, which studies water cycle in global scale, including global evapotranspiration, such as Water Vapor Flux between land and sea.
The topics of study of Mushiake/Oki/Hearht laboratory is classified to Regional Hydrology and Global Hydrology.

Hydrology and Water resource engineering relate to various branches of learning.
Olmost everything conserned with water are treated in Hydrology, not only