The picture illustrates how water circulates in a cyclical manner, which is known as the water cycle.
Overall, the process involves three main stages, namely evaporation, condensation and precipitation, through which the earth gets and maintains the levels of its surface and ground water. Notably, all three forms of water can be seen in this continuous process.
First, as the sun shines in the day time, the surface of oceans gets heated, and the water is converted in to the vapor. As the resulting water vapor is light, it goes up, which is known as the evaporation. Importantly, 80% of the atmospheric water vapor comes from the oceans in this way. After being evaporated, condensation takes place, in which vapor particles combine together to form clouds higher in the sky. When clouds are overloaded and becomes heavier, it accounts for precipitation, whereby water returns to the earth in the form of either rain or snow, from which lakes are filled with and mountain tips are usually covered with, respectively. Once precipitated, certain percentage of water flows on the earth’s surface, known as surface run off, ultimately goes in to rivers and finally to oceans, from which salt water intrudes at merging points. In addition to the surface water, a certain proportion of water is absorbed by the ground and known as the ground water, which can be found above the impervious layer of the earth.
- The flowchart below shows the process involved in completing the work experience requirement for university students Summarize the information by selecting and reporting the main features and make comparisons where relevant 78
- The diagrams below show the stages and equipment used in the cement making process and how cement is used to produce concrete for building purposes Summarize the information by selecting and reporting the main features and make comparisons where relevan 78
- In many parts of the world families were larger in the past because people had more children Do you think there were more advantages or disadvantages to being part of a large family in the past Give reasons for your answer and include any relevant example 89
- In some countries an increasing number of people are suffering from health problems as a result of eating too much fast food It is therefore necessary for governments to impose a higher tax on this kind of food To what extend do you agree or disagree with 67
- The chart below shows the process of waste paper recycling 78