How has water conditioned the Earth’s climate?
12. Think about your attitudes to such things as:
a) The presence of water on the Earth;
b) The characteristics of water;
c) The role of water in nature.
a. LISTENING: Track 13
Listen the passage and unjumble the words
WATER
b. Few is water important how about think people. We do when we’re really thirsty. I remember hiking for hours in really sun anything drink baking without to. I was drinking about dreaming water cool. And when I came to a small river, the water was delicious. And cool. But that was years ago. I that think river the is water polluted in today and dangerous to drink. That’s sad. When I was a kid, water was fun. splash in and could around it You drink it in the countryside. Not today though. Water is becoming more precious and. In fact, there will soon be wars over water. We thinking start to need really more we how and water about it conserve can. Some countries use crazy amounts of water.
C.
Correct the spelling
d. tomrainpt - igbakn -
e. iegndrma - csdieilou -
f. elplotud - hpsasl -
g. sytendrcuio- rpcoiuse -
h. evneosrc - czary -
I. HOMEWORK
1. INTERNET INFO: Search the Internet and find more interesting facts about water. Talk about what you discover with your partner(s) in the next lesson.
GROUNDWATER
READING
Read the text and say where you are likely to find a text like this. Prove your answer.
- in a textbook;
- in a scientific magazine;
- in an encyclopedia.
Groundwater
(1) Groundwater is any water found below the land surface. It is a long-term reservoir of the natural water cycle, as opposed to short-term water reservoirs like the atmosphere and fresh surface water. It is naturally replenished from above, as surface water from precipitation, streams and rivers infiltrates into the ground. The study of distribution and behavior of groundwater and hydrogeology.
(2) Groundwater is found in aquifers, in the pore spaces of rocks, in unconsolidated sediments, as permafrost and as soil moisture. Groundwater flows to the surface naturally at springs and seeps and can form oases and swamps. It may also be tapped artificially by the digging of wells.
(3) Groundwater is often contained in aquifers, which are layers of permeable material that channel the groundwater’s flow. Aquifers can be confined or unconfined. If a confined aquifer follows a downward grade from a recharge zone, groundwater can become pressurized as it flows. This can create artesian wells that flow freely without the need of a pump. The top of the upper unconfined aquifer is called the water table, where water pressure is equal to atmospheric pressure. The region between the land surface and the water table is called the unsaturated zone. Within the this zone water is held to soil particles by adhesion and in pore spaces by capillary action.
(4) Groundwater is highly useful and abundant resource, but it doesn’t renew itself rapidly. If groundwater is extracted intensively from water wells, as for irrigation in arid regions, it may become depleted. The most evident problem, that may result from this is lowering of the water table beyond the rich of existing wells. Wells must consequently be deepened to reach the groundwater; in some places in India, the water table has dropped hundreds of feet due to over extraction.
(5) Not all groundwater problems are caused by over extraction. Pollutants dumped on the ground or in landfills may leach into the soil, and work their way down into aquifers. Movement of water within the aquifer is then likely to spread the pollutant over a wide area, making the groundwater unusable. Areas of karst topography on limestone bedrock are especially vulnerable to surface pollution.