MI BIG
Hydrosphere V.2
Map (html) | Map
(Inspiration)
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All students will describe the characteristics of water and demonstrate
where water is found on the earth.
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All students will describe how water moves.
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All students will analyze the interaction of human activities with the
hydrosphere.
Overview
Our earth, the blue planet, is a closed system in which the water that is
so important to life is cycled over and over. The quality of our lives and
that of our children depends on this resource. This is a difficult concept
for children because they see water coming out of the tap in an unending
supply. Our Great Lakes look like huge bodies of water that we could never
deplete. The Hydrosphere benchmarks focus on the characteristics of water,
where it is found, and how it moves. These are important things to know if
we are to understand the impact that human activities have on the
hydrosphere.
Essential Background Narratives
Describe the characteristics of water and demonstrate where water is found
on the earth.
Describe how water moves.
Analyze the interaction of human activities with the hydrosphere.
When we discuss the hydrosphere we include all the water on the earth.
Though both fresh and salt water represent a tremendous resource and cover
about 75 percent of the earth's surface, students sometimes fail to think
about the water vapor in the air, the snow and ice of the arctic and
mountain tops or the ground water stored in the porous rocks and sediment
beneath the earth's surface.
Elementary students should recognize water in its various states. Young
children seem to have little trouble understanding the solid and liquid
states of water yet frequently assume that when water evaporates it
disappears. Even though it may be more difficult to understand how liquid
water evaporates and then can condense into a liquid again, this concept
is essential to understanding the hydrosphere as a resource.
The amount of water on the earth is finite and it is important to
understand the movement of water. Water moves as a result of gravitational
and wind forces as well as differences in density between warm and cool
water.
Young children should be able to describe water movement, which occurs
around them. The teaching of the water cycle in the elementary years has
been successful. However, students should be able to describe how falling
rain either soaks into the soil or runs off into streams, rivers or lakes.
Middle school students should understand more of the dynamics of water
movement and be able to explain how rainfall in Michigan could reach the
ocean. Additionally, older students need to understand the dynamics of
ground water.
Existing water on the earth cycles through the hydrosphere as ground or
surface water, polar ice caps and atmospheric water vapor. High school
students need to be aware of the special importance of ground water,
precipitation that soaks into the soil. Although groundwater moves more
slowly than surface water, this movement is as important as that of the
surface water. Water that moves through soils and bedrock is filtered. As
such, this water is an important source for human consumption. Students at
this level assume that vast underground lakes and rivers exist, similar to
the ones on the surface.
Young students are most familiar with water they use in their daily lives
for drinking, cleaning, or recreation and often assume water to be
plentiful everywhere and easily replaced. All students need to be aware of
the impact humans have on the hydrosphere. They need to understand how
subtle and wholesale changes in the hydrosphere, such as the construction
of a golf course or a parking lot can have effects on a community. They
should see water as a renewable resource that if managed properly will
continue to be able to sustain life on earth.
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