Hydrologic Cycle

1. Hydrologic Cycle By Hector Marin Jesus Lopez Sammy Barajas Israel Lara

2. Evaporation Precipitation • Precipitation is the primary mechanism for transporting water from the atmosphere to the surface of the earth • There are several forms of precipitation like hail, snow, sleet, and rain • Amounts of precipitation also vary from year to year, like in 1988, an intense drought happened the Midwestern United States, messing up agriculture because there was not enough rain to take care of their crops • In evaporation water is transferred from the surface to the atmosphere, the process by which water changes from a liquid to a gas • Approximately 80% of all evaporation is from the oceans, with the remaining 20% coming from inland water and vegetation

3. Transpiration CONDENSATION • Condensation is the change of water from its gaseous form (water vapor) into liquid • Condensation generally occurs in the atmosphere when warm air rises, cools and looses its capacity to hold water vapor water. • Transpiration is one of the main processes in the water cycle • Transpiration is the evaporation of water into the atmosphere from the leaves and stems of plants • Transpiration accounts for approximately 10% of all evaporating water • Plants absorb soil water through their roots and this water can originate from deep in the soil • Plants pump the water up from the soil to deliver nutrients to their leaves

4. TRANSPORT RUNOFF • Runoff is the movement of land water to the oceans, mainly in the form of rivers, lake • Runoff consists of precipitation that neither evaporates, transpires nor penetrates the surface to become ground waters, and streams • Transport is the movement of water through the atmosphere, specifically from over the oceans to over land • Some of the earth's moisture transport is visible as clouds, which themselves consist of ice crystals and tiny water droplets

5. Main issue within the water cycle • Irrigation is the artificial watering of land that does not get enough water through rainfall in other words they’re the giant sprinklers you see in the fields • The problem with irrigation is that it removes water from its natural source and often causes leaching and run-off where it is used, this removal of nutrients results in farmers using more fertilizers to keep their pastures productive while the waterways become polluted • Another problem is that salt is brought up from lower levels due to irrigation • Unfortunately it removes water from rivers and can cause surface run-off and leaching

6. Effects of irrigation • Irrigation is a problem because it causes a chain of other worse problems • One of the problems is that it causes surface runoff and surface runoff is not only bad for the environment it also causes runoff problems • When runoff flows along the ground, it can pick up soil contaminants such as petroleum, pesticides, or fertilizers

8. References • Man’s impact on the hydrological cycle « David Krohn • http://www.enviroliteracy.org/favicon.ico • 2. The effects of changes in the world hydrological cycle on availability of water resources • Nature current issue RSS feed