Water cycle - class 8. Pptx ( Monalisa )

Water cycle

1. THE WATER CYCLE -BY: ARATI SAHOO UBED20ZOO-010

2. what is water cycle The cycle of processes by which water circulates between the earths oceans, atmosphere and land involving precipitation as rain and snow, drainage in streams and rivers, and return to the atmosphere by evaporation and transpiration.

3. Stages OF WATER CYCLE Evaporation Transpiration Condensation Precipitation Infiltration Surface runoff

4. evaporation One of the major process in the cycle, is the transfer of water from the surface of the earth to the atmosphere. By evaporation water in the liquid state is transferred to the gaseous or vapour state. The main factors affecting evaporation are temperature, humidity, wind speed and solar radiation. The principle source of water vapour is the oceans but evaporation also occurs in soils, snow, ice.

5. TRANSPIRATION Transpiration is the process by which moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapors and is released to the atmosphere Transpiration is essentially evaporation of water from plant leaves. Transpiration rates vary widely depending on weather conditions, such as temperature, humidity, sunlight, soil type, wind, land scope and type of plant.

6. Condensation Condensation is the process by which water vapor in the air is changed into liquid water. Condensation is crucial to the water cycle because it is responsible for the formation of clouds. Clouds form when water vapor condenses around small particles like bits of dust or smoke in the air. Depending on the size of the drops, these particles may or may not be visible.

7. PRECIPITATION Precipitation is water released from clouds in the form of rain, freezing rain, snow or hail. It is the primary connection in the water cycle that provides for the delivery of atmospheric water to the earth. Most precipitation falls as rain. Precipitation forms in the clouds when water vapor condenses into bigger and bigger droplets of water. When the drops are heavy enough, they fall to the earth. If a cloud is colder, like it would be at higher altitude the water droplets may freeze to form ice.

8. INFILTRATION Infiltration is a part of the water cycle and occurs when water moves into the ground from the surface and begins to soak into the soil and rock layers under earth. The water can make its way to the surface from the earth by rain, snow melting or in human activity such as watering.

9. SURFACE RUNOFF Runoff includes not only the waters that travel over the land surface and through channels to reach a stream but also interflow, the water that infiltrates the soil surface and travels by means of gravity towards a stream channels and eventually empties into the channel.

10. IMPPORTANCE OF WATER CYCLE The water cycle is important to all life on earth for many reasons. All living organisms required water and the water cycle describes the process of how water moves through the plants. Plants wouldn’t grow without precipitation. Glaciers, ice and snow can act as stores of fresh water for both human and other organisms. All of these process sustain life and create the ecosystems around us. If water didn’t naturally recycle itself, we would run out of clean water, which is essential to life. It is also involved in maintaining aquatic ecosystem. Greatest natural process which plays a significant role by a continuous movement of water on above and below the surface of earth.

11. THANK YOU