Student/Therapist Resources
Chapter 2: Hydrosphere: One Dynamic Water System
Key Concepts

Water is a naturally occurring substance on our planet found in the frozen, liquid, and
vapor states. The source of all water, for whatever purpose, is the hydrosphere. The
hydrosphere, which is found to exist naturally in the liquid, vapor, or frozen states,
represents the total amount of water on planet Earth, which remains relatively constant at
332 million cubic miles. This entire amount of water is part of one interconnected system,
with many different expressions in the natural environment, including the oceans, rivers,
waterfalls, hot springs, geysers, snow, rain, glaciers, and ice caps.

The hydrosphere is a dynamic system with constant evaporation
(purification) of water, precipitation in the form of mainly rain and
snow, and constant circulation of this water from higher to lower
elevations. This dynamic activity of the hydrosphere is known as the
hydrologic cycle.

Water in the hydrosphere and as it is expressed in the hydrologic cycle
behaves according to the basic principles of the natural behavior of
water as described in Chapter 1. For example, it is the principle of gravity that produces
the flow of water from higher to lower elevation. It is the principle of evaporation that
produces the movement of water from lower to higher elevations.

Human beings are a natural part of the hydrosphere. At any given time, approximately
66 billion gallons of water are inside the total population, and approximately 4 million
gallons of water per minute are flowing into and out of the total population.

Experiences of the healing and therapeutic nature of water in the natural environment—
for example at hot springs, the oceans, and waterfalls—has provided insights into the use
of water as a therapeutic modality. Photo: Body
surfing (courtesy of Greg Rice, Sandy Beach, Ohahu,
Hawaii). Photo: Glenwood Springs, Colorado
(courtesy of Glenwood Hot Springs Pool, Glenwood
Springs, Colorado).

Certain activities of human beings have a negative impact on the hydrosphere, including
toxic chemicals, dumping of garbage, overuse of water, destruction of wetlands, and the
potential negative effects of global warming.
Additional Study, Research, and Teaching Exercises

Hydrosphere
Internet Educational Resources:
HyperPhysics Link (Distribution of water), HyperPhysics Link (Seawater)

Hydrologic Cycle
Internet Educational Resources:
U.S. Geological Survey Link (Hydrologic Cycle); HyperPhysics Link (Hydrologic
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Cycle); Poland Springs Water (Hydrologic Cycle): visit http://www.polandspring.com,
choose the “Know H2O” tab, and then select “our sources” to find information on the
hydrologic cycle.
Teaching Exercise:
Create a dynamic model of the hydrologic cycle as described in Teaching Exercise 2.1.
How can each aspect of the hydrologic cycle be found functioning in this model?

Harming the Hydrosphere
Internet Educational Resource:
U.S. Geological Survey Link (Climate Change)

Drinking Water and Pollution
Internet Educational Resources:
U.S. Environmental Protection Agency (EPA) Link (Drinking Water Containments),
Link (Water Topic)
Scientific Research
Research on Drugs in Drinking Water Use your favorite search engine to find articles on
“research on drugs in drinking water.” Associated Press is a great resource for articles.
Teaching Exercise:
Research the source, treatment procedures, distribution, and other important aspects of
the local municipal water supply. Discuss what home water purification systems should
be used to further purify the local municipal water coming into residential homes to make
it safe for drinking. There is really no one correct approach for this, and there are many
opinions on what is needed, but it is an interesting topic that can provoke a meaningful
discussion.

2
Hydrosphere
Teaching Exercise:
View the different NASA photos of planet Earth to learn more about the hydrosphere and
the hydrologic cycle.
1. How do the photos show that the hydrosphere is one interconnected system?
2. Locate dynamic elements of the hydrosphere—for example, oceans, rivers, lakes, ice
caps, and clouds.
3. Consider how pollution of the hydrosphere by people in a particular location (country)
can affect the total hydrosphere and all living systems connected with it.
4. Why are human beings a natural part of (not separate from) the hydrosphere?
NASA Photos of the Hydrosphere
Australia
http://www.study
hydrotherapy.com/
EarthAustralia14
Inch.jpg
South America,
Africa, Middle
Central America, East, Europe
Caribbean
http://www.study
hydrotherapy.
com/EarthSouth
America14Inch.
jpg
Antarctica
North America,
Northern Ice Cap
http://www.study http://www.study http://www.study
hydrotherapy.com/
hydrotherapy.
hydrotherapy.
com/EarthAfrica com/south_2.jpg EarthforHydroTour.
JPG
14Inch.jpg
* All Links to HyperPhysics appear courtesy of: Copyright HyperPhysics (©C.R. Nave, 2006)
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