Text b Sources of Fresh Water Ground Water

Words:

pore – пора

distinction – различие

spring – источник, родник

substantial – значительный

reverse – поворачивать в противоположном направлении

endorheic – эндогенный – внутреннего происхождения; объясняемый внутренними причинами

Sub-surface water, or groundwater, is fresh water located in the pore space of soil and rocks. It is also water that is flowing within aquifers below the water table. Sometimes it is useful to make a distinction between sub-surface water that is closely associated with surface water and deep sub-surface water in an aquifer (sometimes called "fossil water").

The natural input to sub-surface water is seepage from surface water. The natural outputs from sub-surface water are springs and seepage to the oceans.

If the surface water source is also subject to substantial evaporation, a sub-surface water source may become saline. This situation can occur naturally under endorheic bodies of water, or artificially under irrigated farmland. In coastal areas, human use of a sub-surface water source may cause the direction of seepage to ocean to reverse which can also cause soil salinization. Humans can also cause sub-surface water to be "lost" (i.e. become unusable) through pollution. Humans can increase the input to a sub-surface water source by building reservoirs or ponds.

7. Find in the text international words and give their Russian equivalents.

8. Find in the text the equivalents to the following word combinations:

пористое пространство; в пределах водоносного слоя; ниже водной поверхности; естественный приток; естественный отток; подвергается значительному испарению; становиться солёной; эндогенные водоёмы; орошаемые фермерские земли; прибрежные территории; повысить приток

9. Say if it is true or false.

1. Groundwater is fresh water located in rivers and ponds.

2. Sub-surface water is water that is flowing within aquifers below the water table.

3. The natural input to sub-surface water is seepage from precipitation.

4. The natural outputs from sub-surface water are springs and seepage to the oceans.

5. A sub-surface water source may become saline due to substantial evaporation.

6. Humans can decrease the input to a sub-surface water source by building reservoirs or ponds.

10. Read text C and answer the questions:

1) Why is the amount of water on the globe unchangeable?

2) Where is Earth’s water located?

3) What is the main source of water people use?

Text c Where is Earth's Water Located?

Water is continually moving around, through, and above the Earth as water vapor, liquid water, and ice. In fact, water is continually changing its form. The Earth is pretty much a "closed system," like a terrarium. That means that the Earth neither, as a whole, gains nor loses much matter, including water. Although some matter, such as meteors from outer space, are captured by Earth, very little of Earth's substances escape into outer space. This is certainly true about water. This means that the same water that existed on Earth millions of years ago is still here. Thanks to the water cycle, the same water is continually being recycled all around the globe. It is entirely possible that the water you drank for lunch was once used by ancient man for drinking.

Where is Earth's water located and in what forms does it exist? About 97 percent of all water is in the oceans. Only three percent of all Earth's water is freshwater. The majority, about 69 percent, is locked up in glaciers and icecaps, mainly in Greenland and Antarctica. You might be surprised that of the remaining freshwater, almost all of it is below your feet, as ground water. No matter where on Earth you are standing, chances are that, at some depth, the ground below you is saturated with water. Of all the freshwater on Earth, only about 0.3 percent is contained in rivers and lakes—yet rivers and lakes are not only the water we are most familiar with, it is also where most of the water we use in our everyday lives exists.

Over 99 percent of all water (oceans, seas, ice, most saline water, and atmospheric water) is not available for our uses. And even of the remaining fraction of one percent much of that is out of reach. Considering that most of the water we use in everyday life comes from rivers you'll see we generally only make use of a tiny portion of the available water supplies. The vast majority of the fresh water available for our uses is stored in the ground.

Notice how of the world's total water supply of about 332.5 million cubic miles (about 1,385 million cubic kilometers) of water, over 96 percent is saline. And, of the total freshwater, over 68 percent is locked up in ice and glaciers. Another 30 percent of freshwater is in the ground. Thus, rivers and lakes that supply fresh surface water for human uses only constitute about 22,300 cubic miles (93,100 cubic kilometers), which is about 0.007 percent of total water, yet rivers are the source of most of the water people use.

11. Draw a chart of water distribution on the Earth.

12. Read and translate text D in writing.