The hydrologic cycle can be thought of as a series of reservoirs, or storage areas, and a set of processes that cause water to move between those reservoirs. The largest reservoir by far is the oceans, which hold about 97% of the earth’s water. The remaining 3% is the freshwater so important to our survival, but about 78% of that is stored in ice in Antarctica and Greenland.
About 21% of freshwater on the earth is groundwater, stored insediments and rocks below the surface of the earth. The freshwater that we see in rivers, streams, lakes, and rain is less than 1% of the freshwater on the earth and less than 0.1% of all the water on the earth. Hyderological cycle regulate the climate because it balance the it can dampen climate change.