Glaciers consist of snow that compresses over many years into large,
thickened ice masses. Most of the world’s glacial ice is found in Antarctica
and Greenland, but glaciers are found on nearly continent, even Africa.
Presently. 10% of land area is colours but reflects blue. Almost 90% of an
iceberg is below water; only about 10% shows above water, What makes glaciers
unique is their ability to move. Due to sheer mass, glaciers flow like very
slow rivers. Some glaciers are as small as football fields, whereas others grow
to be over 100 kilometers long.
Within the past 750,000 years, scientists know that there have been eight
ices Age cycle, separated by warmer periods called interglacial periods. Currently,
the earth is nearing the end of an interglacial, meaning that another ice Age
is due in a few thousand years. This is part of the normal climate variation
cycle. Greenhouse warming may delay the onset of another glacial era, but scientists
still have many questions to answer about climate change. Although glaciers
change very slowly over long periods they may provide important global climate
change signals.
The girth of the ice combined with gravity’s influence causes glaciers to
flow very slowly. Once a mass compressed ice reaches a critical thickness of
about 18 meters thick, it becomes so heavy that it begins to deform and move. Ice
may flow down mountains and valleys fan across plains, or spread out to sea. Movement
along the underside of a glacier is slower than movement at the top due to the
friction created as it slides along the ground’s surface.
Most glaciers are found in remote mountainous areas. However some found
near cities or towns present a danger to the people living nearby. On land,
lakes formed on top of a glacier during the melt season may cause floods. At the
narrow part of a valley glacier, ice falling from the glacier presents a hazard
to hikers below. When ice breaks off over the ocean an iceberg is formed. Glaciers
are a natural resource and contain 75% of the world’s freshwater. People
worldwide are trying to harness the power of these frozen streams. Some tones
rely on glacial melting from a nearby ice cap to provide drinking water. Some
farmers spread soil or ashes over snow to promote melting. Hoping that the
melting will provide water to irrigate crops in drought-stricken areas. Others
have channeled melt water from glaciers to their fields. Scientists and
engineers have worked together to tap into glacial resources, using electricity
that has been generated in part by damming glacial melt water.
11.
According to paragraph 4, what is a negative
effect of living too close to a glacier?
A.
The mass of the glacier reaches a critical
thickness.
B.
About 10% of a glacier shows above water.
C.
Spreading dark material over snow promotes
melting.
D.
Lakes formed on top of glaciers may cause floods.
12.
The underlined word remote, as used in paragraph
4 of the passage most nearly means
A.
Isolated.
B.
Nearby
C.
Slow travelling.
D.
Difficult to see
13.
The passage explains that glaciers can be found
where?
A.
Only on Antarctica
B.
Only Greenland and Alaska
C.
N nearly every continent
D.
Only the north and south poles
14.
According to the passage, why does glacial ice
often appear blue?
A.
Because it does not absorb the colour blue.
B.
Because it absorbs all other colours but
reflects blue
C.
Because it does not absorb all other colours including
blue
D.
Because it is blue in colour
15.
After reading the passage, what can one conclude
about glaciers?
A.
There will not be another ice Age coming.
B.
Glaciers have both negative and positive effects
on human life.
C.
Scientists have difficulty studying glaciers.
D.
Scientists have minimal data on the formation of
glaciers.
16.
After reading the passage, what can one infer
about glaciers?
A.
Further exploration is needed to tap the power
of glacial ice in fuelling electric energy.
B.
With variations in climate , glaciers shrink and
expand
C.
Glaciers form in clod regions where the rate of
snowfall is greater than the melting rate of snow
D.
Glaciers are usually bordered at the sides by
rock debris
Answer:
11.
D One
of the hazards of living in a city near a glacier is the possibility that lakes
forming on top of the glacier may flood the city. Although the other answers
are all true statements, none describe negative effects.
12.
A this
passage states that although most glaciers are in remote regions, some are
nearby. The reader needs to understand that the transitional word however
indicates that the word remote means the opposite of near.
13.
C The
passage states that glaciers can be found on nearly every continent.
14.
B This is
the only choice reflected in the passage.
15.
B this
choice is the only one that can be concluded from the passage.
16.
A many examples in the last paragraph suggest
the large potential of untapped electrical power that may be harnessed from glacial
water in the future with further research.
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